Synchronization of the Frenet-Serret linear system with a chaotic nonlinear system by feedback of states

A synchronization procedure of the generalized type in the sense of Rulkov et al [Phys. Rev. E 51, 980 (1995)] is used to impose a nonlinear Malasoma chaotic motion on the Frenet-Serret system of vectors in the differential geometry of space curves. This could have applications to the mesoscopic motion of biological filamentsComment: 12 pages, 7 figures, accepted at Int. J. Theor. Phy

Electrochemical contrast switching between black and white appearance of gelatin-covered zinc

Zinc and its alloys are widely used in the surface protection of metallic structural materials. Thus, zinc is an interesting and relevant candidate material for preparing stimuli-responsive surfaces. In this work, the switching of the optical appearance of zinc between black and white by an applied electrode potential is demonstrated. The zinc surface was covered by gelatin films and subjected to cyclic voltammetry (CV) in a chloride-containing electrolyte which induced pitting corrosion on the zinc surface. Between the different parts of the CV cycles, a reversible change in optical appearance was observed. During the oxidative half-cycles, the surfaces appear white, and during the reductive half-cycles, the surfaces appear brown to black, i.e. dark. Surface characterisation by x-ray photoelectron spectroscopy (XPS) and infrared (IR) spectroscopy shows that the gelatin coating is slightly oxidised during intial stages of the process, but remains intact and present at the surface. Raman spectra prove the presence of ZnO at the interface. Surface analysis shows only minor differences in composition between the black and white surfaces. Based on the available characterisation data, the white appearance associated with anodic currents is attributed to the formation of a non-passivating ZnO. The black appearance associated with cathodic currents is attributed to reduction of surface-confined zinc species, including ZnO and Zn2+. The role of the gelatin is presumably to prevent diffusion of the dissolution products into solution by complex formation and by acting as a diffusion barrier; gelatin will also affect the morphology of the reduction products. A similar switching was observed when gelatin was added to chloride electrolyte; surface analysis showed gelatin adsorption in this case. The black/white switching may, e.g. be useful for surfaces self-indicating corrosion potentials of galvanised steel

1.5V fully programmable CMOS Membership Function Generator Circuit with proportional DC-voltage control

A Membership Function Generator Circuit (MFGC) with bias supply of 1.5 Volts and independent DC-voltage programmable functionalities is presented. The realization is based on a programmable differential current mirror and three compact voltage-to-current converters, allowing continuous and quasi-linear adjustment of the center position, height, width and slopes of the triangular/trapezoidal output waveforms. HSPICE simulation results of the proposed circuit using the parameters of a double-poly, three metal layers, 0.5 μm CMOS technology validate the functionality of the proposed architecture, which exhibits a maximum deviation of the linearity in the programmability of 7 %

H3++H_3^{++} molecular ions can exist in strong magnetic fields

Using the variational method it is shown that for magnetic fields $B\geq 10^{11}$ G there can exist a molecular ion $H_3^{++}$.Comment: LaTeX, 7 pp, 1 table, 4 figures. Title modified. Consideration of the longitudinal size of the system was adde

The Perceived Impact of Online Student Evaluation to the Performance Among Faculty from PUP Branches and Campuses: Basis for Policy Review and Implementation

The study aims to determine the perception of the PUP faculty from branches and campuses about the student’s online evaluation and investigate the implication of results to their performance as teacher in higher education institution. Descriptive and inferential statistics were used to interpret data. The researchers utilizedprimary data through self-administered survey questionnaire and secondary data. Findings revealed that in general, the faculty find the content in four areas of evaluation namely: commitment, knowledge of the subject, teaching for independent learning and management, highly acceptable. They agree with the rating scaleand its equivalent description. The perceived performance of the faculty in four areas showed improvement. The faculty recognized that their personal and social development had improved. When respondents were grouped according to highest educational attainment, significant difference was observed on commitment area. Majority of the faculty felt that students do not fully understand the content of the evaluation instrument, and worst, they use the evaluation as the chance to get even with the professors they dislike. It is recommended to simplify the statements in the instrument. To substantiate the comments and maintain objectivity, the researchers recommend inclusion of students’ personal assessment regarding learning. To further improve the performance of the faculty, deans and chairpersons may identify the administrative concerns of their faculty and identify areas that need training, retraining, coaching, and/or policy revision. Keywords: effective teaching, instruction, faculty performance, student evaluatio

Roles of Candida albicans Mig1 and Mig2 in glucose repression, pathogenicity traits, and SNF1 essentiality.

Metabolic adaptation is linked to the ability of the opportunistic pathogen Candida albicans to colonize and cause infection in diverse host tissues. One way that C. albicans controls its metabolism is through the glucose repression pathway, where expression of alternative carbon source utilization genes is repressed in the presence of its preferred carbon source, glucose. Here we carry out genetic and gene expression studies that identify transcription factors Mig1 and Mig2 as mediators of glucose repression in C. albicans. The well-studied Mig1/2 orthologs ScMig1/2 mediate glucose repression in the yeast Saccharomyces cerevisiae; our data argue that C. albicans Mig1/2 function similarly as repressors of alternative carbon source utilization genes. However, Mig1/2 functions have several distinctive features in C. albicans. First, Mig1 and Mig2 have more co-equal roles in gene regulation than their S. cerevisiae orthologs. Second, Mig1 is regulated at the level of protein accumulation, more akin to ScMig2 than ScMig1. Third, Mig1 and Mig2 are together required for a unique aspect of C. albicans biology, the expression of several pathogenicity traits. Such Mig1/2-dependent traits include the abilities to form hyphae and biofilm, tolerance of cell wall inhibitors, and ability to damage macrophage-like cells and human endothelial cells. Finally, Mig1 is required for a puzzling feature of C. albicans biology that is not shared with S. cerevisiae: the essentiality of the Snf1 protein kinase, a central eukaryotic carbon metabolism regulator. Our results integrate Mig1 and Mig2 into the C. albicans glucose repression pathway and illuminate connections among carbon control, pathogenicity, and Snf1 essentiality

Shape analysis and tracking of migrating macrophages

Cell migration is important in many human processes of development and disease. In Cancer, migration can be related to metastasis or cell defects. A precise analysis of the cell shapes in biological studies could lead to insights about migration. Therefore, this paper describes an algorithm to iteratively segment, track and analyse the shape of macrophages from fluorescent microscopy image sequences. This process allows observation of shape variations as the cells migrate. The algorithm identifies and separates overlapping and non-overlapping cells, then for the non-overlapping cases analyses the shape and extracts a series of measurements, including the number of "corner" or pointy edges through a multiscale angle variation matrix, anglegram. The shape evolution algorithm was tested on fluorescently labelled macrophages observed on embryos of Drosophila melanogaster

Analysis of the Interactions of Migrating Macrophages

Understanding the migrating patterns of cells in the immune system is of great importance; especially the changes of direction and its cause. For macrophages and other immune cells, excessive migration could be related to autoimmune diseases and cancer. In this work, an algorithm to analyse the change in direction of cells before and after they interact with another cell is proposed. The main objective is to provide insights into the notion that interactions between cell structures appear to anticipate migration. Such interactions are determined when the cells overlap and form clumps of two or more cells. The algorithm integrates a segmentation technique capable of detecting overlapping cells and a tracking framework into a tool for the analysis of the trajectories of cells before and after they overlap. The preliminary results show promise into the analysis and the hypothesis proposed, and it lays the ground work for further developments

CARACTERÍSTICAS Clínicas e Epidemiológicas da Pitiríase versicolor em Pacientes Atendidos no Hospital Universitário Cassiano Antônio Moraes Vitória (Espírito Santo Brasil) e no Instituto Dermatológico Dr. Huberto Bogaert Diaz Santiago de Los Caballeros República Dominicana

Introdução: A Pitiríase Versicolor (PV) é infecção fúngica crônica, superficial, provocada pela levedura, Malassezia spp. Desencadeada em pessoas de qualquer idade, predomina na faixa etária entre 20 e 30 anos; afeta igualmente os sexos e as raças. A clínica da PV se caracteriza pelo surgimento de máculas hipopigmentadas ou hiperpigmentadas, com descamação furfurácea, em áreas seborreicas do corpo, moderadamente pruriginosas, circulares ou ovais, pequenas no inicio, logo podendo se confluir em grandes áreas. O diagnóstico pode ser feito mediante luz de Wood e o exame micológico. Objetivos: descrever e comparar as características clínicas e epidemiológicas da PV nos pacientes atendidos em dois hospitais: um no Espírito Santo Brasil (HUCAM) e outro na República Dominicana (IDCP). Metodologia: Foi realizado um estudo descritivo de delineamento transversal, no período do 01 de novembro de 2015 até 30 de novembro 2016, tendo como critérios de inclusão pacientes diagnosticados clínica e laboratorialmente com PV. Foram determinadas as frequências das variáveis sócio-demográficas dos pacientes e clínicas das lesões de PV e se realizou o teste estatístico de Qui quadrado (X2). Resultados: Um total de 95 pacientes foram estudados, 53 pacientes do HUCAM e 42 do IDCP. A faixa etária mais acometida foi entre 21 e 30 anos nos dois grupos. O sexo feminino foi o mais frequente no IDCP Rep. Dom. com 27 (64,3%) e no HUCAM com 36 (67,9%) pacientes, sem diferença estatística nesses grupos. No grupo do IDCP-Rep. Dom., a PV apareceu em 19 (45,2%) pacientes de origem mista e no HUCAM, em 30 (56,6%) pacientes negros/pardos. Predominaram as lesões hipocrômicas nos dois grupos, presentes em 30 (71,4%) pacientes no grupo do IDCP-Rep. Dom. e 34 (64,2%) pacientes no grupo do HUCAM. No grupo do IDCP-Rep. Dom. as lesões surgiram há menos de um ano em 41 (97,6%) pacientes e no grupo do HUCAM em 35 (66%) pacientes, com diferença estatística significante (p=0,000) entre os dois grupos. A localização das lesões foi semelhante nos dois grupos, sendo o tórax e o dorso as áreas mais afetadas. Segundo o relato dos pacientes, 31 (73,8%) tinham história anterior de PV no grupo do IDCP-Rep. Dom. e 34 (64,2%) no grupo do HUCAM. As culturas para as leveduras Malassezia spp não produziram fungos viáveis, não sendo possível a identificação das espécies determinantes das lesões de PV em nenhum dos casos do estudo. Conclusão: Os resultados mostraram que os grupos foram semelhantes, provavelmente pelas características geográficas e étnicas de ambos os cenários

Testing the product test

The product test asks the product of a quantity index number and a price index number to equal the corresponding value change. The literature treats the product test as being so important that it is used to identify acceptable index number pairs, and to construct implicit index numbers when an otherwise desirable pair fails the test. We treat the product test as a hypothesis to be tested, and we provide an empirical application