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

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 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

Genetic and Functional Analyses of SHANK2 Mutations Suggest a Multiple Hit Model of Autism Spectrum Disorders

Autism spectrum disorders (ASD) are a heterogeneous group of neurodevelopmental disorders with a complex inheritance pattern. While many rare variants in synaptic proteins have been identified in patients with ASD, little is known about their effects at the synapse and their interactions with other genetic variations. Here, following the discovery of two de novo SHANK2 deletions by the Autism Genome Project, we identified a novel 421 kb de novo SHANK2 deletion in a patient with autism. We then sequenced SHANK2 in 455 patients with ASD and 431 controls and integrated these results with those reported by Berkel et al. 2010 (n = 396 patients and n = 659 controls). We observed a significant enrichment of variants affecting conserved amino acids in 29 of 851 (3.4%) patients and in 16 of 1,090 (1.5%) controls (P = 0.004, OR = 2.37, 95% CI = 1.23-4.70). In neuronal cell cultures, the variants identified in patients were associated with a reduced synaptic density at dendrites compared to the variants only detected in controls (P = 0.0013). Interestingly, the three patients with de novo SHANK2 deletions also carried inherited CNVs at 15q11-q13 previously associated with neuropsychiatric disorders. In two cases, the nicotinic receptor CHRNA7 was duplicated and in one case the synaptic translation repressor CYFIP1 was deleted. These results strengthen the role of synaptic gene dysfunction in ASD but also highlight the presence of putative modifier genes, which is in keeping with the "multiple hit model" for ASD. A better knowledge of these genetic interactions will be necessary to understand the complex inheritance pattern of ASD

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

FMECA and FTA analysis applied to the manufacturing process of pulsating heat pipes

Pulsating heat pipes (PHPs) offer significant advantages for the thermal control of electronic components due to their simple manufacturing and high heat transfer rates. The reliability of PHPs has traditionally been assessed through long-life testing, but detailed reliability analyses from an equipment perspective are limited. The study of PHP reliability is essential due to its application and operational conditions. For instance, in aerospace applications these devices operate under severe conditions, and maintenance or replacement is impossible during operation, making them critical components in system functionality. The reliability analysis of PHPs focuses on the manufacturing process, considering future operating conditions. Although preliminary PHP testing will be conducted on Earth, laboratory conditions are less stringent due to the difficulty of replicating launch acceleration and space conditions for long-term testing under microgravity. This study presents an FMECA (Failure Modes, Effects, and Criticality Analysis) of the pulsating heat pipe manufacturing process, breaking down the production of each component. The results indicate that the most critical point is concentrated in the assembly of these components, leading to a higher incidence of welding failures. It recommends further work to improve welding and analyze mechanical stresses within the heat pipe

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