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"Generating electricity is not only inefficient, it also makes pedal power less sustainable, less robust and more costly. To begin with, batteries have to be manufactured, and they have to be replaced regularly. This requires energy, which can completely negate the ecological advantage of pedal power. According to this research paper (pdf), the embodied energy of a 150Wh lead-acid battery (like the one offered with the Windstream pedal power generator) is at least 37,500 Wh, which equals 250 full charges of the battery (more sources: 1/2). In other words: if you can deliver 75 watts of power to the battery, you have to pedal for 500 hours in order to generate the energy that was needed to manufacture the battery. Because the life expectancy of a lead-acid battery can be as low as 300 discharge/charge cycles (sources: 1/2), you are basically pedalling to produce the energy required to manufacture the battery. If you also factor in the embodied energy of other electronics and parts, the ecological advantage of a pedal powered generator connected to a battery becomes rather doubtful. It might costs more energy than it delivers."

"Generating electricity is not only inefficient, it also makes pedal power less sustainable, less robust and more costly. To begin with, batteries have to be manufactured, and they have to be replaced regularly. This requires energy, which can completely negate the ecological advantage of pedal power. According to this research paper (pdf), the embodied energy of a 150Wh lead-acid battery (like the one offered with the Windstream pedal power generator) is at least 37,500 Wh, which equals 250 full charges of the battery (more sources: 1/2). In other words: if you can deliver 75 watts of power to the battery, you have to pedal for 500 hours in order to generate the energy that was needed to manufacture the battery. Because the life expectancy of a lead-acid battery can be as low as 300 discharge/charge cycles (sources: 1/2), you are basically pedalling to produce the energy required to manufacture the battery. If you also factor in the embodied energy of other electronics and parts, the ecological advantage of a pedal powered generator connected to a battery becomes rather doubtful. It might costs more energy than it delivers."

"Burden of Poverty Lacking money or time can lead one to make poorer decisions, possibly because poverty imposes a cognitive load that saps attention and reduces effort. Mani et al. (p. 976; see the Perspective by Vohs) gathered evidence from shoppers in a New Jersey mall and from farmers in Tamil Nadu, India. They found that considering a projected financial decision, such as how to pay for a car repair, affects people's performance on unrelated spatial and reasoning tasks. Lower-income individuals performed poorly if the repairs were expensive but did fine if the cost was low, whereas higher-income individuals performed well in both conditions, as if the projected financial burden imposed no cognitive pressure. Similarly, the sugarcane farmers from Tamil Nadu performed these tasks better after harvest than before. Abstract The poor often behave in less capable ways, which can further perpetuate poverty. We hypothesize that poverty directly impedes cognitive function and present two studies that test this hypothesis. First, we experimentally induced thoughts about finances and found that this reduces cognitive performance among poor but not in well-off participants. Second, we examined the cognitive function of farmers over the planting cycle. We found that the same farmer shows diminished cognitive performance before harvest, when poor, as compared with after harvest, when rich. This cannot be explained by differences in time available, nutrition, or work effort. Nor can it be explained with stress: Although farmers do show more stress before harvest, that does not account for diminished cognitive performance. Instead, it appears that poverty itself reduces cognitive capacity. We suggest that this is because poverty-related concerns consume mental resources, leaving less for other tasks. These data provide a previously unexamined perspective and help explain a spectrum of behaviors among the poor. We discuss some implications for poverty policy."

"Burden of Poverty Lacking money or time can lead one to make poorer decisions, possibly because poverty imposes a cognitive load that saps attention and reduces effort. Mani et al. (p. 976; see the Perspective by Vohs) gathered evidence from shoppers in a New Jersey mall and from farmers in Tamil Nadu, India. They found that considering a projected financial decision, such as how to pay for a car repair, affects people's performance on unrelated spatial and reasoning tasks. Lower-income individuals performed poorly if the repairs were expensive but did fine if the cost was low, whereas higher-income individuals performed well in both conditions, as if the projected financial burden imposed no cognitive pressure. Similarly, the sugarcane farmers from Tamil Nadu performed these tasks better after harvest than before. Abstract The poor often behave in less capable ways, which can further perpetuate poverty. We hypothesize that poverty directly impedes cognitive function and present two studies that test this hypothesis. First, we experimentally induced thoughts about finances and found that this reduces cognitive performance among poor but not in well-off participants. Second, we examined the cognitive function of farmers over the planting cycle. We found that the same farmer shows diminished cognitive performance before harvest, when poor, as compared with after harvest, when rich. This cannot be explained by differences in time available, nutrition, or work effort. Nor can it be explained with stress: Although farmers do show more stress before harvest, that does not account for diminished cognitive performance. Instead, it appears that poverty itself reduces cognitive capacity. We suggest that this is because poverty-related concerns consume mental resources, leaving less for other tasks. These data provide a previously unexamined perspective and help explain a spectrum of behaviors among the poor. We discuss some implications for poverty policy."

"The Fairphone is a modular handset designed with repairability and ethical sourcing of its materials as headline features. It sold 60,000 units. Amazingly, for what sounds like a nerd-phone, almost half of those buyers had never owned a smartphone before. Now the Fairphone 2 is launching, and with a totally-new, in-house design. The new phone is even easier to repair, and because it was wholly designed by the FairPhone team, its supply chain is even more responsible than ever. The Fairphone is thicker than the latest iPhone or Samsung flagship, but that's the point. Instead of packing everything into a tiny case and keeping it there with glue, the Fairphone is designed to be taken apart. The lightweight magnesium frame supports modules that can be easily replaced by the user. "We have designed it with an aim to last three to five years, looking at making it robust and modular-for repairability," says Fairphone's chief communications officer, Tessa Wernink. "Obviously how long it lasts depends quite heavily on the user, so what we as a company are doing is offering an ecosystem around the phone that supports long-lasting use, first-hand or second-hand." Inside the case (itself one of several options) you'll find the core unit, containing all the chips and radios; a replaceable battery pack; a display that can be snapped off and replaced without any tools (not even a screwdriver); a receiver unit, which contains the front camera, sensors; the headset connector and microphones; a speaker/vibrator unit; and a camera module. These modules are designed to balance manufacturing complexity with repairability. For instance, the display comes as a standalone unit, but less-vulnerable components are bundled into one module. The camera, which people are most likely to upgrade as better versions become available, is also housed in its own module. That way you don't need to toss out your whole phone just to get a better camera. "In fact, the motto from the maker mo

"The transition from unicellular to multicellular life was one of a few major events in the history of life that created new opportunities for more complex biological systems to evolve. Predation is hypothesized as one selective pressure that may have driven the evolution of multicellularity. Here we show that de novo origins of simple multicellularity can evolve in response to predation. We subjected outcrossed populations of the unicellular green alga Chlamydomonas reinhardtii to selection by the filter-feeding predator Paramecium tetraurelia. Two of five experimental populations evolved multicellular structures not observed in unselected control populations within ~750 asexual generations. Considerable variation exists in the evolved multicellular life cycles, with both cell number and propagule size varying among isolates. Survival assays show that evolved multicellular traits provide effective protection against predation. These results support the hypothesis that selection imposed by predators may have played a role in some origins of multicellularity."

"Carbon dioxide (CO2) is a gas essential for life- animals exhale it, plants sequester it. It exists in Earth's atmosphere in comparably small concentrations, but is vital for sustaining life. CO2 is termed a greenhouse gas (GHG) - a gas which absorbs and emits thermal radiation creating the 'greenhouse effect'. Along with other greenhouse gases, such as nitrous oxide and methane, CO2 is important in sustaining a habitable temperature for the planet: if there were absolutely no GHGs, our planet would be simply too cold. It has been estimated that without these gases, the average surface temperature of the Earth would be about -18 degrees celcius.1 Since the Industrial Revolution, however, energy-driven consumption of fossil fuels has led to a rapid increase in emissions of CO2, disrupting the global carbon cycle and leading to a planetary warming impact. As an international community, UN member parties have set a target of limiting average warming to 2 degrees celcius above pre-Industrial temperatures."

"A kit to build a mechanical display that cycles through the numbers 0-9 by turning a crank. Do you love building mechanical contraptions? Complicated looking gear trains that perform some task? Then this kit is for you ! However, beware. It is not for the faint-hearted. The assembly instructions are 26 pages long. The counter comprises of well over 100 parts. If you want to take it even further you can install a motor and drive it automatically."

"Según Kolb, a la hora de aprender se ponen en juego cuatro capacidades diferentes: Capacidad de Experiencia Concreta (EC): ser capaz de involucrase por completo, abiertamente y sin prejuicios en experiencias nuevas. Capacidad de Observación Reflexiva (OR): ser capaz de reflexionar acerca de estas experiencias y de observarlas desde múltiples perspectivas. Capacidad de Conceptualización Abstracta (CA): ser capaz de crear nuevos conceptos y de integrar sus observaciones en teorías lógicamente sólidas. Capacidad de Experimentación Activa (EA): ser capaz de emplear estas teorías para tomar decisiones y solucionar problema David A. Kolb y Roger Fry crearon el conocido como "Círculo del aprendizaje a través de la experiencia". Los autores argumentan que el aprendizaje puede comenzar en cualquiera de los cuatro puntos, aunque los más habitual sea comenzar por una experiencia concreta. Igualmente señalan que más que un círculo, debe entenderse la progresión cognitiva como una espiral que va pasando sucesivamente por cada uno de los cuatro tipos de actividades. Como desarrollo de este modelo, los autores propusieron un cuadro de estilos cognitivos: dado que no era habitual que los distintos individuos fueran igualmente capaces en los cuatro tipos de actividad, podían distinguirse cuatro estilos según sus competencias se inclinasen más por un tipo de actividad u otro."

"Según Kolb, a la hora de aprender se ponen en juego cuatro capacidades diferentes: Capacidad de Experiencia Concreta (EC): ser capaz de involucrase por completo, abiertamente y sin prejuicios en experiencias nuevas. Capacidad de Observación Reflexiva (OR): ser capaz de reflexionar acerca de estas experiencias y de observarlas desde múltiples perspectivas. Capacidad de Conceptualización Abstracta (CA): ser capaz de crear nuevos conceptos y de integrar sus observaciones en teorías lógicamente sólidas. Capacidad de Experimentación Activa (EA): ser capaz de emplear estas teorías para tomar decisiones y solucionar problema David A. Kolb y Roger Fry crearon el conocido como "Círculo del aprendizaje a través de la experiencia". Los autores argumentan que el aprendizaje puede comenzar en cualquiera de los cuatro puntos, aunque los más habitual sea comenzar por una experiencia concreta. Igualmente señalan que más que un círculo, debe entenderse la progresión cognitiva como una espiral que va pasando sucesivamente por cada uno de los cuatro tipos de actividades. Como desarrollo de este modelo, los autores propusieron un cuadro de estilos cognitivos: dado que no era habitual que los distintos individuos fueran igualmente capaces en los cuatro tipos de actividad, podían distinguirse cuatro estilos según sus competencias se inclinasen más por un tipo de actividad u otro."