Segregation method as possible process to beneficiate oxidized lead ores

In this investigation it has been demonstrated that the Segregation Process has merit for treating oxidized lead ores. The process comprises heating the crushed ore with salt and coal at about 750° C. to produce metallic lead attached to the carbon particles, which then is recovered by conventional flotation methods. The quantities of sodium chloride and coal required for the best segregation of lead obtained in this work was 1.0 percent of coal and 1.0 percent of salt by weight. Good segregation was obtained by using salt and coal as fine as 65 or 48 mesh. Segregation varied with the roasting temperature and time. At least 60 minutes was required for good segregation at 750° C. About 3 to 4 percent moisture was required for segregation at 750° C. Some valuable metals like silver, bismuth, precipitate along with the lead on the carbon particles. It is concluded that the process appears to have considerable merit on siliceous ores that are not amenable to conventional processing methods --Abstract, page 2

Modelling of the interaction between peptides and graphitic surfaces

The aim of this thesis is to understand the interactions of peptides with graphitic surfaces such as carbon nanotubes and graphite, in order to help establish guiding principles for the design of peptide sequences with controllable affinity to graphitic surfaces. Atomistic molecular dynamics (MD) simulations with our extended polarisable AMOEBAPRO force-field, which includes parameters for graphitic surfaces is used throughout. The peptide sequences studied were identified by phage-display experiments for their strong affinity to CNTs, and are rich in tryptophan and histidine residues [94]. The importance of the tryptophan residues on the binding affinity to CNTs is investigated by mutating each tryptophan by either tyrosine and phenylalanine. In addition, the effect of the surface curvature on the binding affinity is also explored. It is found that sequences containing tryptophan residues have more affinity to graphitic surfaces than those containing tyrosine or phenylalanine. Furthermore, it is suggested that these peptide sequences were selected for interfacial shape, since in the case of graphite, a compromise between having all the aromatic residues close to the surface and also allowing the non-aromatic residues to approach the surface is found. Following this study, the interaction of peptide sequences with CNTs is again studied, but this time with the aim to investigate the order of the residues, on the binding affinity to CNTs. The influence of the peptide sequence on the binding affinity to CNTs is studied by scrambling the sequence (HWKHPWGAWDTL). This study suggests that binding affinity is strongly dependent on the order of the content of the peptide sequences and gives some useful insights to the identification of principles that may help in the design of peptide sequences with controllable binding affinity to CNTs. For instance, it is found that strong binding may be due to the presence of isolated pairs of tryptophans, while weaker binding may be due to the presence of two tryptophan residues intercalated by another residue. The interactions of water with graphitic surfaces – CNTs, fullerenes and graphite – are also considered and it is found that the water structuring at the interface is weak and that there are no more than tree layers of structured water on the graphitic surfaces. Finally, the effect of the presence of OH defects on CNTs on the binding affinity to peptides is investigated. The results show that the binding affinity is not significantly affected by the presence of OH defects, but a general increase in the peptide mobility is noticed, giving insights for the applications of real CNTs with peptides. The work described in this thesis helps to understand what are the key residues involved in the interaction with CNTs, why do these key residues bind better to CNTs and provide insights on the mechanisms of peptided binding to CNTs, by demonstrating the role of peptide conformation

Evaluación del impacto del método Sirani en la preparación para la escritura en niños de 4 a 6 años de edad del orfanato Chávez de la Rosa, Arequipa, 2016

El presente trabajo se denomina «Evaluación del Impacto del Método Sirani en la preparación para la escritura en niños de 4 a 6 años de edad del orfanato Chávez de la Rosa». Se escogió una muestra de dieciocho niños(as) de 4 a 6 años de edad del orfanato Chávez de la Rosa en Arequipa. El diseño de la investigación comenzó con el Pre-Test, que fue aplicado en el mes de Febrero; y el Post-Test, aplicado en junio. El método Sirani fue desarrollado durante marzo, abril, mayo y la primera semana de junio. Se midió inicialmente su Motricidad Fina con el fin de ver en qué grado se encuentra el niño al momento de aplicar el Pre-Test. Después de haber aplicado el método Sirani, se aplicó nuevamente el Post-Test y, en los resultados que se obtuvieron, se encontró que los niños lograron una mejora en su motricidad fina. Con este método los niños alcanzarán un mejor desarrollo en la preparación para la escritura.Tesi

3D comparison of dental arch stability in patients with and without cleft lip and palate after orthodontic/rehabilitative treatment

This study aimed to compare the linear dimensions of the dental arches of adult patients with complete unilateral cleft lip and palate (UCLP) after orthodontic and prosthetic treatment with fixed partial dentures (FPD) to patients without clefts, using 3D technology. This retrospective longitudinal study sample consisted of 35 subjects divided into two groups. Included in this sample were 15 complete UCLP individuals who had received orthodontic treatment before rehabilitation with a fixed partial denture (FG), as well as 20 patients without cleft as control group (CG). All patients were aged between 18 and 30 years. Digital dental casts were obtained in two stages: (T1) end of orthodontic treatment and (T2) one year after prosthetic rehabilitation (FG); and (T1) end of orthodontic treatment and (T2) one year after removal of the orthodontic appliance (CG). Intercanine, interfirst premolar and intermolar distances, and incisor-molar length were obtained. A precalibrated and trained examiner performed the assessments. Intergroup differences between T2 and T1 were compared between the groups using the t test or Mann-Whitney test with a significance level of 5% (p<0.05). The intercanine distance variation (T2-T1) showed statistical difference (p=0.005) increasing in the FG group and decreasing in the CG group. In the interfirst premolar distance variation, FG decreased, while CG increased with statistically significant difference (p=0.008). The intercanine distance of individuals with cleft showed stability, while that of the CG had no stability. The CG showed stability in the interfirst premolar distance, while FG had no stability. These findings showed that the FPD is capable of restricting orthodontic results, leading to a stabilization of the dental arches

Dimensionality of Carbon Nanomaterials Determines the Binding and Dynamics of Amyloidogenic Peptides: Multiscale Theoretical Simulations

Experimental studies have demonstrated that nanoparticles can affect the rate of protein self-assembly, possibly interfering with the development of protein misfolding diseases such as Alzheimer's, Parkinson's and prion disease caused by aggregation and fibril formation of amyloid-prone proteins. We employ classical molecular dynamics simulations and large-scale density functional theory calculations to investigate the effects of nanomaterials on the structure, dynamics and binding of an amyloidogenic peptide apoC-II(60-70). We show that the binding affinity of this peptide to carbonaceous nanomaterials such as C60, nanotubes and graphene decreases with increasing nanoparticle curvature. Strong binding is facilitated by the large contact area available for π-stacking between the aromatic residues of the peptide and the extended surfaces of graphene and the nanotube. The highly curved fullerene surface exhibits reduced efficiency for π-stacking but promotes increased peptide dynamics. We postulate that the increase in conformational dynamics of the amyloid peptide can be unfavorable for the formation of fibril competent structures. In contrast, extended fibril forming peptide conformations are promoted by the nanotube and graphene surfaces which can provide a template for fibril-growth

Diffusion of hydrophobin proteins in solution and interactions with a graphite surface

<p>Abstract</p> <p>Background</p> <p>Hydrophobins are small proteins produced by filamentous fungi that have a variety of biological functions including coating of spores and surface adhesion. To accomplish these functions, they rely on unique interface-binding properties. Using atomic-detail implicit solvent rigid-body Brownian dynamics simulations, we studied the diffusion of HFBI, a class II hydrophobin from <it>Trichoderma reesei</it>, in aqueous solution in the presence and absence of a graphite surface.</p> <p>Results</p> <p>In the simulations, HFBI exists in solution as a mixture of monomers in equilibrium with different types of oligomers. The oligomerization state depends on the conformation of HFBI. When a Highly Ordered Pyrolytic Graphite (HOPG) layer is present in the simulated system, HFBI tends to interact with the HOPG layer through a hydrophobic patch on the protein.</p> <p>Conclusions</p> <p>From the simulations of HFBI solutions, we identify a tetrameric encounter complex stabilized by non-polar interactions between the aliphatic residues in the hydrophobic patch on HFBI. After the formation of the encounter complex, a local structural rearrangement at the protein interfaces is required to obtain the tetrameric arrangement seen in HFBI crystals. Simulations performed with the graphite surface show that, due to a combination of a geometric hindrance and the interaction of the aliphatic sidechains with the graphite layer, HFBI proteins tend to accumulate close to the hydrophobic surface.</p

Cheminformatics Research at the Unilever Centre for Molecular Science Informatics Cambridge.

The Centre for Molecular Informatics, formerly Unilever Centre for Molecular Science Informatics (UCMSI), at the University of Cambridge is a world-leading driving force in the field of cheminformatics. Since its opening in 2000 more than 300 scientific articles have fundamentally changed the field of molecular informatics. The Centre has been a key player in promoting open chemical data and semantic access. Though mainly focussing on basic research, close collaborations with industrial partners ensured real world feedback and access to high quality molecular data. A variety of tools and standard protocols have been developed and are ubiquitous in the daily practice of cheminformatics. Here, we present a retrospective of cheminformatics research performed at the UCMSI, thereby highlighting historical and recent trends in the field as well as indicating future directions.J. E. F thanks the Medical Research Council for funding (Grant Number MR/K020919/1). Furthermore, the UCMSI acknowledges all funding sources for continuous support over the past 15 years.This is the final published version. It first appeared at http://onlinelibrary.wiley.com/doi/10.1002/minf.201400166/abstract

ATLANTIC BIRDS: a data set of bird species from the Brazilian Atlantic Forest

South America holds 30% of the world's avifauna, with the Atlantic Forest representing one of the richest regions of the Neotropics. Here we have compiled a data set on Brazilian Atlantic Forest bird occurrence (150,423) and abundance samples (N = 832 bird species; 33,119 bird individuals) using multiple methods, including qualitative surveys, mist nets, point counts, and line transects). We used four main sources of data: museum collections, on-line databases, literature sources, and unpublished reports. The data set comprises 4,122 localities and data from 1815 to 2017. Most studies were conducted in the Florestas de Interior (1,510 localities) and Serra do Mar (1,280 localities) biogeographic sub-regions. Considering the three main quantitative methods (mist net, point count, and line transect), we compiled abundance data for 745 species in 576 communities. In the data set, the most frequent species were Basileuterus culicivorus, Cyclaris gujanensis, and Conophaga lineata. There were 71 singletons, such as Lipaugus conditus and Calyptura cristata. We suggest that this small number of records reinforces the critical situation of these taxa in the Atlantic Forest. The information provided in this data set can be used for macroecological studies and to foster conservation strategies in this biodiversity hotspot. No copyright restrictions are associated with the data set. Please cite this Data Paper if data are used in publications and teaching events. © 2017 by the Ecological Society of Americ

&nbsp;

O propósito do presente estudo foi comparar as variações das dimensões lineares dos arcos dentários de pacientes com fissura labiopalatina após o tratamento ortodôntico e protético com prótese parcial fixa e pacientes sem fissura labiopalatina imediatamente após a ortodontia e pelo menos um ano após a remoção do aparelho ortodôntico. Este estudo longitudinal retrospectivo, foi composto por uma amostra de 70 modelos digitais, dos quais 30 modelos eram de pacientes com fissura labiopalatina unilateral completa, que receberam uma prótese parcial fixa na região da fissura (n=15), grupo fissura (GF); e 40 modelos de pacientes sem fissura labiopalatina (n=20), grupo controle (GC); com idade entre 18 e 30 anos. Os modelos foram obtidos em dois tempos: (T1) término do tratamento ortodôntico, e (T2) pelo menos 1 ano após a reabilitação protética (GF); e (T1) término do tratamento ortodôntico e (T2) pelo menos um ano após remoção do aparelho ortodôntico (GC). As medidas das dimensões dos arcos dentários foram realizadas diretamente nas imagens escaneadas, por meio do Scanner 3Shapes R700TM e mensuradas pelo Software Appliance Designer. As dimensões avaliadas foram: distância inter-caninos, distância inter-1os. pré-molares, distância inter-molares, e comprimento incisivo-molar. Um examinador previamente calibrado e treinado realizou as avaliações. Foram realizadas comparações entre os grupos, em tempos distintos (T1 e T2); e na diferença entre T2 e T1 nos grupos (GF e GC); utilizando o teste T ou de Mann- Whitney, com um nível de significância de 5% (p<0.05). Houve diferença estatística (p=0,005) no valor da variação de T2-T1 na distância inter-caninos com aumento da distância no GF e diminuição no GC. Na variação da distância inter-prémolar o GF apresentou diminuição do valor e o GC mostrou aumento, com diferença estatisticamente significativa (p=0,008). Nos demais parâmetros (inter-molar e incisivo molar) não houve diferença estatística. Não houve estabilidade no GC na distância inter-caninos e observou-se estabilidade no GF, não houve estabilidade no GF na distância inter-pré molar e houve estabilidade no GC. A Prótese Parcial Fixa estabiliza os resultados obtidos com a ortodontia.The aim of the present study was to compare the linear dimensions of dental arches of patients with cleft lip and palate following orthodontic and prosthetic treatment with fixed partial denture and patients without cleft lip and palate immediately after orthodontics and at least one year after removal of the orthodontic appliance. This retrospective longitudinal study consisted of a sample of 70 digital models, of which 30 models were from patients with complete unilateral cleft lip and palate, who received a fixed partial prosthesis in the cleft region (n = 15), cleft lip and palate group (CLPG); and 40 patient models without cleft lip and palate (n = 20), control group (CG); aged between 18 and 30 years. The models were obtained in two stages: (T1) end of orthodontic treatment, and (T2) at least 1 year after prosthetic rehabilitation (CLPG); and (T1) end of orthodontic treatment and (T2) at least one year after removal of the orthodontic appliance (CG). Measurements of the dimensions of the dental arches were performed directly on the scanned images, using the 3Shape\'s R700TM Scanner and measured by the Appliance Designer Software. The dimensions evaluated were: inter-canine distance, inter-1st premolars distance, intermolar distance, and incisormolar length. A pre-calibrated and trained examiner performed the assessments. Comparisons were made between the groups at different times (T1 and T2); and in the difference between T2 and T1 in the groups (CLPG and CG); using the T or Mann- Whitney test, with a significance level of 5% (p <0.05). There was a statistical difference (p = 0.005) in the value of the T2-T1 variation in the intercanine distance with increase in the ClG distance and decrease in the CG. In the interprémolar distance variation the ClG presented a decrease in value and the CG showed an increase, with a statistically significant difference (p = 0.008). In the other parameters (intermolar and molar incisors) there was no statistical difference. There was not stability in the CG in the intercanine distance and there was stability in the CLPG, there was stability in the CG in the inter-pre-molar distance and there was no stability in the CLPG. Partial Fixed Prosthesis stabilizes the results obtained with orthodontics

Avaliação através de estereofotogrametria, de medidas faciais antropométricas utilizadas para obtenção da dimensão vertical de oclusão

Restoring the occlusal vertical dimension (OVD) in occlusal imbalance, multiple dental absences, and severe wear is essential to achieving satisfactory oral rehabilitation. Despite several methods to determine the OVD, there is no single and precise. The present study aimed to use stereophotogrammetry to assess the relationship between facial measurements and compare metrics techniques to obtain OVD among individuals aged ranging 20 to 65 years. The analysis was performed on 186 patients divided into four groups: G1 - 46 patients aged between 20 and 30 years; G2 - 35 patients aged 31 to 40 years; G3 - 50 patients aged 41 to 50 years; G4 - 55 patients aged 51 to 65 years. Relevant anthropometrics landmarks relationship to OVD were pointed on the face, and 3D images were obtained using the Vectra H1 (Canfield Scientific, Inc, Fairfield, NJ, USA) portable stereophotogrammetry camera system. The linear measurements were measured by VAM elaboration software (Canfield Scientific, Inc). Linear regression analysis was performed to evaluate the relationships between the measurements of the lower third of the face (Sn-Gn and Prn-Pg). The ANOVA was applied to compare the Sn-Gn measurements with the measurements from the outer corner of the eyes to the straight lines of the commissures in the vertical direction (Exo R/L-Ch\'R/L) in the evaluated groups. P < .05 was considered significant. Through multiple linear regression, 13 linear measures predictive of OVD were evaluated, and only four were considered statistically significant for the Sn-Gn model: Exo R Ch\' R; ExoL EndL x2; EndR EndL x2 and sex. For the Prn-Pg model, three independent variables showed a statistically significant difference: Exo R-Ch\' R; Exo L-Ch\'L, and Exo L-End Lx2. The ExoR-Ch\'R and ExoL-EndoLx2 predictors significantly impact the OVD through stereophotogrammetry. Comparing the groups (ANOVA) and the Sn-Gn measurements concerning the outer corner of the eyes (ExoR/L) and the straight line of the commissure (Ch\'R/L) and the pupil (PupilR/L) and the straight line of the commissure (Ch\'\'R/L), both vertically, the results showed a statistically significant difference in all measurements except PupilL-Ch\'\'L. It is concluded that the Willis method, which establishes the measurement from the outer corner of the eye to the straight line of the commissure as a method to obtain the OVD, only has relevance in the measurement of the pupil to the left straight line of the commissure (PupilL/Ch\'L). Not finding support in the other measures to establish OVD with stereophotogrammetry.Restabelecer a dimensão vertical de oclusão (DVO), quando não há estabilidade oclusal e ausências múltiplas dentárias além de desgastes acentuados, é fundamental para atingir uma reabilitação oral satisfatória. Apesar da existência de vários métodos para determinar a DVO não há um método único e preciso. O presente trabalho se propôs a utilizar da estereofotogrametria para observar a relação entre medidas antropométricas da face e comparar as técnicas métricas para obtenção da DVO entre indivíduos de 20 a 65 anos. A análise foi realizada em 186 pacientes divididos em quatro grupos: G1 - 46 pacientes de 20 a 30 anos de idade; G2 - 35 pacientes de 31 a 40 anos de idade; G3 - 50 pacientes de 41 a 50 anos de idade; G4 - 55 pacientes de 51 a 65 anos de idade. As fotografias 3D foram obtidas utilizando o sistema portátil de câmera de estereofotogrametria Vectra H1 (Canfield Scientific, Inc, Fairfield, NJ, EUA). Pontos morfométricos foram estabelecidos na face previamente a captura da imagem e, através do software VAM elaboration (Canfield Scientific, Inc), medidas lineares de relevância para a avaliação da DVO foram mensuradas. Regressão linear múltipla avaliou a relação entre as medidas do terço inferior da face (Sn-Gn e Prn-Pg). O ANOVA foi aplicado para comparar as medidas de Sn-Gn com as medidas do canto externo dos olhos às linhas retas dirigidas lateralmente as comissuras, no sentido vertical (Exo R/L-ChR/L) nos grupos avaliados. O nível de significância de .05 foi considerado significativo. Através da regressão linear múltipla, 13 medidas lineares preditoras da DVO foram avaliadas e apenas 4 foram consideradas estatisticamente significativas para o modelo Sn-Gn: Exo R Ch´ R; ExoL EndL x2; EndR EndL x2 e sexo. Para o modelo Prn-Pg, três variáveis independentes apresentaram diferença estatisticamente significativa: Exo R-Ch R; Exo L-ChL e Exo L-End Lx2. Os preditores ExoR-ChR e ExoL-EndoLx2 impactam significativamente a DVO, através da estereofotogrametria. Quando se comparou os grupos (ANOVA) e as medidas de Sn-Gn em relação ao canto externo dos olhos (ExoR/L) e a linha reta da comissura (ChR/L) e a pupila (PupilR/L) e a linha reta da comissura (ChR/L), ambas no sentido vertical, os resultados mostraram diferença estatisticamente significativa em todas as medidas exceto em PupilL-ChL. Conclui-se que o método de Willis, que estabelece a medida do canto externo do olho à linha da comissura direcionada lateralmente e que se encontra com a linha vertical do canto externo do olho, como método para estabelecer a DVO só apresenta relevância na medida da pupila à comissura do lado esquerdo (PupilL/ChL), não encontrando respaldo nas demais medidas para estabelecimento da DVO com a estereofotogrametria