From Outsiders to On-Paper Equals to Cultural Curiosities? The Trajectory of Diversity in the USA

This paper examines the genesis and trajectory of diversity in the USA. It argues that unfortunately diversity was more a product of market interests and differential processes in the recruitment of workers at different times and for different purposes than a smooth process of incorporation of immigrant groups from different cultures and continents. At the end, diversity assumed a highly hierarchical form with blacks at the bottom and whites at the top within a framework of manifest destiny and inequality. Confronting an unequal status, non-whites engaged in group-based struggles that transformed them into political communities and the process into a social struggle. The paper concludes with a call for European countries to learn from this experience and try to preempt it by moving to incorporate newcomers in such a way that they become fully contributing members of the societies they enter within a mutually transforming processDiversity, Race Relations, Racial Politics, Immigrants, Identity Formation

Tracking end-of-life stage of chemicals: A scalable data-centric and chemical-centric approach.

[EN]Chemical flow analysis (CFA) can be used for collecting life-cycle inventory (LCI), estimating environmental releases, and identifying potential exposure scenarios for chemicals of concern at the end-of-life (EoL) stage. Nonetheless, the demand for comprehensive data and the epistemic uncertainties about the pathway taken by the chemical flows make CFA, LCI, and exposure assessment time-consuming and challenging tasks. Due to the continuous growth of computer power and the appearance of more robust algorithms, data-driven modelling represents an attractive tool for streamlining these tasks. However, a data ingestion pipeline is required for the deployment of serving data-driven models in the real world. Hence, this work moves forward by contributing a chemical-centric and data-centric approach to extract, transform, and load comprehensive data for CFA at the EoL, integrating cross-year and country data and its provenance as part of the data lifecycle. The framework is scalable and adaptable to production-level machine learning operations. The framework can supply data at an annual rate, making it possible to deal with changes in the statistical distributions of model predictors like transferred amount and target variables (e.g., EoL activity identification) to avoid potential data-driven model performance decay over time. For instance, it can detect that recycling transfers of 643 chemicals over the reporting years (1988 to 2020) are 29.87%, 17.79%, and 20.56% for Canada, Australia, and the U.S. Finally, the developed approach enables research advancements on data-driven modelling to easily connect with other data sources for economic information on industry sectors, the economic value of chemicals, and the environmental regulatory implications that may affect the occurrence of an EoL transfer class or activity like recycling of a chemical over years and countries. Finally, stakeholders gain more context about environmental regulation stringency and economic affairs that could affect environmental decision-making and EoL chemical exposure predictions.USEP

Sugar cane bagasse as feedstock for second generation ethanol production. Part I: Diluted acid pretreatment optimization

Tons of sugar cane bagasse are produced in Brazil as waste of the sugar and ethanol industries. This lignocellulosic material is a potential source for second-generation ethanol production. Diluted acid hydrolysis is one of the most efficient pretreatments for hemicellulosic solubilization. The hydrolysate obtained is rich in xylose, which can be converted to ethanol by Pichia stipitis. This work used a statistical approach and the severity factor to investigate the effects of factors associated with the diluted acid hydrolysis process (acid concentration, solid:liquid ratio and time of exposure) on various response variables (xylose concentration, hydrolysis yield, inhibitor concentration and hydrolysate fermentability). The severity factor had a strong influence on the generation of inhibitors. The statistical analysis was useful for determining the effects of the individual factors and their interactions on the response variables. An acid concentration of 1.09% (vv), an S:L ratio of 1:2.8 (g:ml), and an exposure time of 27 min were established and validated as the optimum pretreatment conditions for the generation of hydrolysates with high xylose concentration and low contents of inhibitors. In such conditions, hydrolysate with 50 g/l of xylose was obtained

Automatic translation of the dactilologic language of hearing impaired by adaptive systems

Una de las principales limitaciones que presentan las personas con discapacidad auditiva está directamente relacionada con su dificultad para interactuar con otras personas, ya sea de forma verbal o a través de sistemas auxiliares basados en la voz y el audio. En este artículo se presenta el desarrollo de un sistema integrado de hardware y software, para el reconocimiento automático del lenguaje dactilológico de señas utilizado por personas con este tipo de discapacidad. El hardware está compuesto por un sistema inalámbrico adherido a un guante, el cual posee un conjunto de sensores que capturan una serie de señales generadas por los movimientos gestuales de la mano, y un modelo por adaptación basado en los principios de la computación neuronal, el cual permite su reconocimiento en términos de un lenguaje dactilológico en particular. Los resultados arrojados por el sistema integrado mostraron gran efectividad en el reconocimiento de las vocales que conforman el lenguaje dactilológico en español, esto gracias a la capacidad que posee el modelo de asociar un conjunto de señales de entrada, con un movimiento dactilológico en particular.One of the main limitations of the people with hearing impairment is directly related to their difficulty interacting with others, either verbally or through auxiliary systems based on voice and audio. This paper presents the development of an integrated system of hardware and software for automatic fingerspelling sign language used by people with this type of disability. The hardware system comprises a glove which has a set of wireless sensors that capture a series of signals generated by the hand gestures, and a adaptive model based on the principles of neural computation, that allows recognition of a particular dactilologic language. Results from the integrated system showed great effectiveness in recognizing vowels from the dactilologic Spanish language. This recognition was influenced by the dimensionality reduction made by the neural model of the input signals representing movements, and the sensitivity factor that sets the limit between recognition and learning

Sugar cane bagasse as feedstock for second generation ethanol production. Part II: Hemicellulose hydrolysate fermentability

Sugar cane bagasse is produced in Brazil as waste of the sugar and ethanol industries. This lignocellulosic material is a potential source for second-generation ethanol production; however a pretreatment stage is essential, which aims at removing the hemicellulose component by disorganizing the lignocellulosic complex. In this work sugar cane bagasse was pretreated by diluted acid hydrolysis resulting in xylose-rich hydrolysates, which could be fermented to ethanol by a strain of the yeast Pichia stipitis. Statistical approach was used to investigate the effects of factors associated with the diluted acid hydrolysis process (acid concentration, solid:liquid ratio and time of exposure) on the fermentability of different hydrolysates. The statistical analysis was useful for determining the effects of the individual factors and their interactions on the response variables. An acid concentration of 1.09% (v/v), a solid:liquid ratio of 1:2.8 (g:ml), and an exposure time of 27 min were established and validated as the optimum pretreatment conditions for ethanol production from hemicellulose hydrolysates of sugar cane bagasse. Under these conditions, a hydrolysate with 50 g/l of xylose, 6.04 g/l of acetic acid, 0.55 g/l of hydroxylmethylfurfural and 0.09 g/l of furfural was obtained and its fermentation yielded roughly 20 g/l of ethanol in 40 hrs

LCPOM: Precise Reconstruction of Polarized Optical Microscopy Images of Liquid Crystals

When viewed with a cross-polarized optical microscope (POM), liquid crystals display interference colors and complex patterns that depend on the material's microscopic orientation. That orientation can be manipulated by application of external fields, which provides the basis for applications in optical display and sensing technologies. The color patterns themselves have a high information content. Traditionally, however, calculations of the optical appearance of liquid crystals have been performed by assuming that a single-wavelength light source is employed, and reported in a monochromatic scale. In this work, the original Jones matrix method is extended to calculate the colored images that arise when a liquid crystal is exposed to a multi-wavelength source. By accounting for the material properties, the visible light spectrum and the CIE color matching functions, we demonstrate that the proposed approach produces colored POM images that are in quantitative agreement with experimental data. Results are presented for a variety of systems, including radial, bipolar, and cholesteric droplets, where results of simulations are compared to experimental microscopy images. The effects of droplet size, topological defect structure, and droplet orientation are examined systematically. The technique introduced here generates images that can be directly compared to experiments, thereby facilitating machine learning efforts aimed at interpreting LC microscopy images, and paving the way for the inverse design of materials capable of producing specific internal microstructures in response to external stimuli.Comment: 12 pages, 5 figures (main text). 6 pages, 6 figures (appendices

Application of Chlorella sp. and Scenedesmus sp. in the bioconversion of urban leachates into industrially relevant metabolites

This paper explores the ability of Chlorella sp. and Scenedesmus sp. to convert landfill leachates into usable metabolites. Different concentrations (0.5, 1, 5, and 10% v/v) of leachate coupled with an inorganic carbon source (Na2CO3, and NaHCO3) were tested to improve biomass production, metabolites synthesis, and removal of NO3 and PO4 . The result shows that both strains can effectively grow in media with up to 5% (v/v) leachate, while significantly reducing the concentrations of NO3, and PO4 (80 and 50%, respectively). The addition of NaHCO3 as a carbon source improved the final concentration of biomass, lipids, carbohydrates, and the removal of NO3 and PO4 in both strains

Minimally invasive robotic surgery: force and torque analysis

La cirugía mínimamente invasiva y la incorporación de la robótica en este tipo de procedimientos representa grandes ventajas para el paciente, el cirujano y los sistemas de salud. Sin embargo, los dispositivos comerciales disponibles en la actualidad no cuentan con realimentación de fuerza y tacto, que faciliten al cirujano la identificación de los tejidos y consecuentemente, la reducción de errores en los procedimientos quirúrgicos; por lo cual, el desarrollo de sistemas que cuenten con este tipo de realimentación se convierte en un tema de interés a nivel mundial. El presente artículo contiene una revisión del estado de la técnica con respecto a los sistemas comerciales y experimentales desarrollados en esta área. También, se presentan algunos sensores y modelos matemáticos utilizados para calcular las fuerzas y torques en cirugía mínimamente invasiva.Minimally Invasive Surgery and the adaptation of robotics to these procedures represent many advantages for the patient, the surgeon, and the health program. However, commercial devices used nowadays lack haptic feedback. This fact makes the tissue identification more difficult and increments the injuries risk during the surgical procedure. The development of systems with this kind of feedback has become a topic of interest throughout the world. The present article contains a revision of the state of the art about commercial and experimental systems developed in this area. Models for the force and torque propagation, used in Minimally Invasive Surgery, are also presented