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Synthetic membranes have long been a powerful platform to reconstruct life’s functions and shed light on the origin-of-life. More recently, they have been employed as convenient model systems to reconstitute membrane proteins, allowing their biochemical characterization and use in applications such as nanopore sequencing. While several techniques rely on commercially available phospholipids to form functional membranes, a grand challenge is the de novo construction of synthetic membranes in a manner that more closely mimics native lipid membrane generation in cells. Chemoselective coupling reactions have been used to generate cell-like synthetic lipid membranes. These methodologies suffer from distinct limitations, including the use of considerable amounts of micelle forming amphiphilic precursors that can interrupt lipid bilayer formation. Here we describe a novel de novo phospholipid synthesis strategy to rapidly form biomimetic membranes at physiological conditions in the micromolar concentration range, without the use of amphiphilic starting materials. The methodology takes advantage of oxime dialkylation via the condensation of two simple water-soluble precursors, a short-chain aldehyde and a dihydroxylamine-containing phosphocholine to afford a dual oxime phospholipid. Our strategy enables the chemoselective synthesis of phospholipids, which spontaneously self-assemble into membrane-bound vesicles. Membrane formation takes place in biologically relevant aqueous solution, and is stable in the presence of a variety of biomolecules and small polar molecules. Advantageously, we were able to reconstitute a membrane protein via in situ oxime phospholipid formation without the use of initial detergent solubilization. The oxime-based reconstitution technology can be used as a powerful tool for the straightforward fabrication of proteoliposomes, enabling thus to investigate membrane protein structure and function. We believe our novel chemoselective phospholipid synthe

Previous studies suggest a stronger influence of visual signals on body image in individuals with eating disorders (EDs) than healthy controls; however, the influence of other exteroceptive sensory signals remains unclear. Here we used an illusion relying on auditory (exteroceptive) signals to manipulate body size/weight perceptions and investigated whether the mechanisms integrating sensory signals into body image are altered in subclinical and clinical EDs. Participants’ footstep sounds were altered to seem produced by lighter or heavier bodies. Across two experiments, we tested healthy women assigned to three groups based on self-reported Symptomatology of EDs (SED), and women with Anorexia Nervosa (AN), and used self-report, body-visualization, and behavioural (gait) measures. As with visual bodily illusions, we predicted stronger influence of auditory signals, leading to an enhanced body-weight illusion, in people with High-SED and AN. Unexpectedly, High-SED and AN participants displayed a gait typical of heavier bodies and a widest/heaviest visualized body in the ‘light’ footsteps condition. In contrast, Low-SED participants showed these patterns in the ‘heavy’ footsteps condition. Self-reports did not show group differences. The results of this pilot study suggest disturbances in the sensory integration mechanisms, rather than purely visually-driven body distortions, in subclinical/clinical EDs, opening opportunities for the development of novel diagnostic/therapeutic tools.

Negative body perceptions are a major predictor of physical inactivity, a serious health concern. Sensory feedback can be used to alter such body perceptions; movement sonification, in particular, has been suggested to affect body perception and levels of physical activity (PA) in inactive people. We investigated how metaphorical sounds impact body perception and PA. We report two qualitative studies centered on performing different strengthening/flexibility exercises using SoniBand, a wearable that augments movement through different sounds. The first study involved physically active participants and served to obtain a nuanced understanding of the sonifications’ impact. The second, in the home of physically inactive participants, served to identify which effects could support PA adherence. Our findings show that movement sonification based on metaphors led to changes in body perception (e.g., feeling strong) and PA (e.g., repetitions) in both populations, but effects could differ according to the existing PA-level. We discuss principles for metaphor-based sonification design to foster PA.

A physical characterization of the drainage area of the Bahía de Navidad, Jalisco, Mexico was carried out, based on different parameters and hydrographic indices. The results allowed to identify and define more precisely the baseline of the hydrographic behavior of three small “sub” basins that drain and flow into Pacific Ocean. 1) Arroyo El Pedregal a high-risk creek impacts independently on San Patricio-Melaque, 2) Arroyo El Organito a moderate risk creek runs into El Tule lagoon, and surrounding urbanized areas, 3) Arroyo Seco it is low hazard that determines the hydrological conditions of Barra de Navidad lagoon. In conclusion, environmental deterioration, high degree of ecological fragmentation and deforestation, coupled with hydrographic specificities calculated by indexes, makes them highly susceptible in different degrees to situations of risk and emergency due to floods and alluvial landslides, in face of increasingly frequent and powerful hydrometeorological events in recent years., Con base en diferentes parámetros e índices hidrográficos se realizó una caracterización física del área de drenaje de la Bahía de Navidad, Jalisco, México. Los resultados permitieron identificar, y definir con mayor precisión las bases del comportamiento hidrográfico de tres pequeñas subcuencas que drenan y desembocan en el océano Pacífico; 1) Arroyo El Pedregal de peligrosidad alta impacta de manera independiente sobre San Patricio-Melaque, 2) Arroyo El Organito de peligrosidad moderada desemboca en laguna El Tule, y zonas urbanizadas aledañas, 3) Arroyo Seco de baja peligrosidad determina las condiciones hidrológicas de laguna Barra de Navidad. Se concluye que el deterioro ambiental, alto grado de fragmentación ecológica y deforestación, aunados a especificidades hidrográficas calculadas por los índices, las hace altamente susceptibles en diferentes grados a situaciones de riesgo y emergencia por inundaciones, aluviones y deslaves ante eventos hidrometeorológicos cada vez más frecuentes y potentes de los últimos años.

Se presentan los resultados obtenidos durante los muestreos realizados en tres campañas oceanográficas denominadas DEM I (Mayo-Junio 1995), DEM II (Noviembre-Diciembre-1995) y DEM III (Marzo 1996) a bordo del barco de investigación pesquera BIP V, correspondientes a la distribución y abundancia de los crustáceos de la Familia Portunidae -también conocidos como jaibas-, de la plataforma continental de Jalisco y Colima, en el Pacífico oriental mexicano. Se recolectaron siete especies, de las cuales, Portunus xantusii affinis fue la más abundante numéricamente, ya que constituyó el 77,1% del grupo estudiado. Se registraron diferencias significativas de la abundancia relativa en relación a la profundidad, el sitio de muestreo y la época de colecta. Se observó que Portunus xantusii affinis es una especie que se distribuye en profundidades de 60-80 m, mientras que las restantes especies se encuentran principalmente en profundidades menores (20-40 m). Se discute la importancia de las jaibas en relación a su potencial pesquero y su gran incidencia en los arrastres camaroneros.

Se analizó la estructura de tallas y proporción sexual de Squilla hancocki Squilla panamensis (Crustacea: Stomatopoda) en las costas de Jalisco y Colima, México. Durante 1996 y 1997 se realizaron muestreos mensuales en la Bahía de Navidad y Playa El Coco, desde los 20 a 80 m de profundidad utilizando redes de arrastres camaroneras. En general, S. hancocki presentó una proporción sexual de un macho por cada hembra (1:1), mientras que en S. panamen is la proporción sexual estuvo a favor de las hembras (1,2:0,9). Las tallas promedio de las hembras de S. hancocki fueron mayores en diciembre de 1997 (80 mm) mientras que para los machos se presentaron en agosto de 1996 (78,4 mm). En el caso de S. panamensis las mayores tallas se presentaron en octubre de 1997 para las hembras, con un promedio de 82,4 mm y en septiembre del mismo año para los machos, con un promedio de 97 mm. La prueba de Duncan permitió definir que en Bahía de Navidad se encuentran las mayores tallas de S. hancocki, a los 40 m de profundidad. Para S. panamensis no se detectaron diferencias entre la distribución de tallas por sitios, sin embargo, se pudo apreciar que las tallas máximas se localizan entre los 20 y 40 de profundidad. En ambas especies los machos resultaron ser más grandes en promedio que las hembras. La estructura de tallas presentó variaciones a través de los meses en ambas especies. Las tallas mejor representadas fueron entre los 60 y 70 mm de longitud total para S. hancocki y entre 65 y 85 mm en S. panamensis.