Single molecule thermodynamics of ATP synthesis by F1_1-ATPase

F$_\mathrm{o}$F$_1$-ATP synthase is a factory for synthesizing ATP in virtually all cells. Its core machinery is the subcomplex F$_1$-motor (F$_1$-ATPase) and performs the reversible mechanochemical coupling. Isolated F$_1$-motor hydrolyzes ATP, which is accompanied by unidirectional rotation of its central $\gamma$-shaft. When a strong opposing torque is imposed, the $\gamma$-shaft rotates in the opposite direction and drives the F$_1$-motor to synthesize ATP. This mechanical-to-chemical free-energy transduction is the final and central step of the multistep cellular ATP-synthetic pathway. Here, we determined the amount of mechanical work exploited by the F$_1$-motor to synthesize an ATP molecule during forced rotations using methodology combining a nonequilibrium theory and single molecule measurements of responses to external torque. We found that the internal dissipation of the motor is negligible even during rotations far from a quasistatic process.Comment: 10 pages, 4 figure

Calidad asistencial en la División de Enfermería Materno Infantil de un Hospital Universitario, según la óptica de los enfermeros

O objetivo deste estudo foi analisar a qualidade assistencial na Divisão de Enfermagem Materno-Infantil do Hospital Universitário da USP, fundamentado no modelo Donabediano. Os dados foram obtidos em agosto de 2006, empregando-se um questionário, respondido por 55 sujeitos. A análise dos dados ocorreu segundo índices percentuais e testes específicos. O Alpha de Cronbach do instrumento foi 0,71, demonstrando confiabilidade. Na dimensão de estrutura, 98,2% dos enfermeiros consideraram adequado o local do carro de emergência e 63,6% apontaram dificuldades em participar das atividades educacionais. Em processo, 96,4% concordaram que o SAE é um instrumento de melhoria da qualidade, e 72,7% apontaram dificuldades na comunicação com os profissionais de saúde. Para resultado, 72,7% indicaram que a prescrição de enfermagem atende às necessidades dos usuários. A dimensão de estrutura obteve o pior escore, média de 38,5. Acredita-se que este estudo subsidie ações de melhoria da qualidade nas três dimensões, sobretudo, na de estrutura.The objective of the present study was to analyze the quality of health care at the Maternal-Child Division of a Hospital of University of São Paulo, based on the Donabedian model. Data collection was performed in August of the year 2006, using a questionnaire that was answered by 55 subjects. Data analysis was performed by means of percentage rates and specific tests. A Cronbach's Alpha of 0.71 was found for the instrument, thus showing reliability. As for structure, 98.2% of nurses considered the emergency car location appropriate, and 63.6% reported difficulties in participating in educational activities. As for process, 96.4% consider that the SAE is an instrument that improves quality, and 72.7% stated having communication difficulties with health care professionals. As for the results, 72.7% reported that the nursing prescription meets the users' needs. Structure was the aspect with the worst score, a mean of 38.5. This study supports actions to improve quality in the three domains, particularly structure.El objetivo de este estudio fue examinar la calidad asistencial en la División de Enfermería Materno Infantil del Hospital Universitario de la USP de acuerdo con el modelo de Donabedian. Los datos fueron obtenidos en agosto de 2006, empleándose un cuestionario que fue respondido por 55 sujetos. El análisis de los datos se efectuó a través de índices porcentuales y tests específicos. El Alpha de Cronbach del instrumento fue de 0,71, lo que demuestra la fiabilidad del estudio. En la dimensión de estructura 98,2% de los enfermeros consideró adecuada la localización de la ambulancia de Emergencias, y 63,6% mencionaron tener dificultades para participar de las actividades educativas. En proceso, el 96,4% estuvo de acuerdo en que el SAE es una herramienta para el mejoramiento de la calidad y el 72,7% se refirió a las dificultades en la comunicación con los profesionales de la salud. Para el resultado, 72,7% indicó que las indicaciones de enfermería responden a las necesidades de los usuarios. La dimensión de la estructura obtuvo la peor puntuación, con un promedio de 38,5. Se cree que el estudio contribuya a trazar líneas de acción para el mejoramiento de calidad en las tres dimensiones estudiadas, particularmente en la estructura.Fundação de Apoio à Pesquisa do Estado de São Paulo (FAPESP

Cancer progression by breast tumors with Pit-1-overexpression is blocked by inhibition of metalloproteinase (MMP)-13

INTRODUCTION: The POU class 1 homeobox 1 transcription factor (POU1F1, also known as Pit-1) is expressed in the mammary gland and its overexpression induces profound phenotypic changes in proteins involved in cell proliferation, apoptosis, and invasion. Patients with breast cancer and elevated expression of Pit-1 show a positive correlation with the occurrence of distant metastasis. In this study we evaluate the relationship between Pit-1 and two collagenases: matrix metalloproteinase-1 (MMP-1) and matrix metalloproteinase-13 (MMP-13), which have been related to metastasis in breast cancer. METHODS: We began by transfecting the MCF-7 and MDA-MB-231 human breast adenocarcinoma cell lines with the Pit-1 overexpression vector (pRSV-hPit-1). Afterward, the mRNA, protein, and transcriptional regulation of both MMP-1 and MMP-13 were evaluated by real-time PCR, Western blot, chromatin immunoprecipitation (ChIP), and luciferase reporter assays. We also evaluated Pit-1 overexpression with MMP-1 and MMP-13 knockdown in a severe combined immunodeficiency (SCID) mouse tumor xenograft model. Finally, by immunohistochemistry we correlated Pit-1 with MMP-1 and MMP-13 protein expression in 110 human breast tumors samples. RESULTS: Our data show that Pit-1 increases mRNA and protein of both MMP-1 and MMP-13 through direct transcriptional regulation. In SCID mice, knockdown of MMP-13 completely blocked lung metastasis in Pit-1-overexpressing MCF-7 cells injected into the mammary fat pad. In breast cancer patients, expression of Pit-1 was found to be positively correlated with the presence of both MMP-1 and MMP-13. CONCLUSIONS: Our data indicates that Pit-1 regulates MMP-1 and MMP-13, and that inhibition of MMP-13 blocked invasiveness to lung in Pit-1-overexpressed breast cancer cells. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13058-014-0505-8) contains supplementary material, which is available to authorized users

Information heat engine: converting information to energy by feedback control

In 1929, Leo Szilard invented a feedback protocol in which a hypothetical intelligence called Maxwell's demon pumps heat from an isothermal environment and transduces it to work. After an intense controversy that lasted over eighty years; it was finally clarified that the demon's role does not contradict the second law of thermodynamics, implying that we can convert information to free energy in principle. Nevertheless, experimental demonstration of this information-to-energy conversion has been elusive. Here, we demonstrate that a nonequilibrium feedback manipulation of a Brownian particle based on information about its location achieves a Szilard-type information-energy conversion. Under real-time feedback control, the particle climbs up a spiral-stairs-like potential exerted by an electric field and obtains free energy larger than the amount of work performed on it. This enables us to verify the generalized Jarzynski equality, or a new fundamental principle of "information-heat engine" which converts information to energy by feedback control.Comment: manuscript including 7 pages and 4 figures and supplementary material including 6 pages and 8 figure

#IronyOff – Understanding the Usage of Irony on Twitter during a Corporate Crisis

Many companies have faced challenges of social media in the form of public social crises. Previous research on social media crisis communication focuses specifically on examining communication patterns, text content, and user structures. However, ironic communication that takes place during corporate crises has hardly been investigated. To contribute to this field, we gathered Twitter data about a major global corporate crisis and conducted a social network analysis. Moreover, we started an online survey to examine user groups and their personal and social motives for the use of irony. Our study revealed that certain community clusters exist that use irony specifically for the purpose of entertainment and pastime. Based on the findings of this paper, managers can adapt and expand their strategies in crisis communication. Further research papers in information systems could use the implicit display theory and our suggested methods for detecting and understanding irony in social media communication

The European construction social partners: gender equality in theory and practice

This article explores the social partners' role in the gender equality agenda in construction at skilled operative level. It draws on a survey of the European construction social partners that investigated the presence of women in skilled trades and the policies, collective agreements and practices that play a role in women's integration. The responses indicate that the construction industry still displays inertia and conservatism, and that the social partners corroborate rather than counter this. They express a 'discourse' of gender equality, but this does not automatically lead to equal opportunity policies or programmes. The social partners have the platform to make inroads and to change the industry from within, but need further encouragement to put this on their agenda

Reaction mechanism and characteristics of T_{20} in d + ^3He backward elastic scattering at intermediate energies

For backward elastic scattering of deuterons by ^3He, cross sections \sigma and tensor analyzing power T_{20} are measured at E_d=140-270 MeV. The data are analyzed by the PWIA and by the general formula which includes virtual excitations of other channels, with the assumption of the proton transfer from ^3He to the deuteron. Using ^3He wave functions calculated by the Faddeev equation, the PWIA describes global features of the experimental data, while the virtual excitation effects are important for quantitative fits to the T_{20} data. Theoretical predictions on T_{20}, K_y^y (polarization transfer coefficient) and C_{yy} (spin correlation coefficient) are provided up to GeV energies.Comment: REVTEX+epsfig, 17 pages including 6 eps figs, to be published in Phys. Rev.

Didáctica especial y prácticas de la enseñanza

AnualMateriaPrograma N° 04127Aprobado Resolución N° 2347/1

Measurement of the Inner Retinal Layers of Megalopapilla by Optical Coherence Tomography

The main purpose of this study was to assess the differences in the peripapillary retinal nerve fiber layer (pRNFL) and ganglion cell-inner plexiform layer (GCIPL) thicknesses between subjects with megalopapilla (MP) and those with large (physiological) cup discs (LCD) measured by spectral-domain optical coherence tomography. The secondary purpose was to determine whether pRNFL and GCIPL thicknesses increase with the optic nerve head (ONH) area. This cross-sectional study included 184 eyes (92 eyes with MP and 92 eyes with LCD). The subjects with LCD were used as sex-and-age-matched controls. All subjects were imaged using the Cirrus HD-OCT system. Macula and pRNFL thickness maps were obtained for all subjects. The inferior quadrant pRNFL thickness was higher in the MP group than in the LCD group (P < 0.05). There were no differences in the GCIPL thickness between the two groups. A positive correlation was found between average, superior, and inferior quadrant pRNFL thicknesses and the ONH area (P < 0.05). The slope of the correlation curve was higher for the inferior quadrant. No correlation was found between the GCIPL thickness and the ONH area. In comparison to patients with LCD, the inferior quadrant pRNFL thickness of patients with MP was higher. As the ONH area increased, the average, superior, and inferior quadrant pRNFL thicknesses also increased. In patients with MP, the assessment of a glaucomatous lesion based on pRNFL thickness measurements may not be reliable. It is recommended that in these patients, the evaluation of glaucomatous damage be based on the GCIPL thickness map analysis rather than on the pRNFL thickness.Â