The Calm Before the Storm? - Anticipating the Arrival of General Purpose Technologies

This paper presents a Schumpeterian quality-ladder model incorporating the impact of new General Purpose Technologies (GPTs). GPTs are breakthrough technologies with a wide range of applications, opening up new innovational complementarities. In contrast to most existing models which focus on the events after the arrival of a new GPT, the model developed in this paper focuses on the events before the arrival if R&D firms know the point of time and the technological impact of this drastic innovation. In this framework we can show, that the economy goes through three main phases: First, the economy is in its old steady state. Second, there are transitional dynamics and finally, the economy is in a new steady state with higher growth rates. The transitional dynamics are characterized by oscillating cycles. Shortly before the arrival of a new GPT, there is an increase in R&D activities and growth going even beyond the old steady state levels and immediately before the arrival of the new GPT, there is a large slump in R&D activities using the old GPT.Schumpeterian growth, research and development, general purpose technologies

Long-Term Growth Driven by a Sequence of General Purpose Technologies

We present a Schumpterian model of endogenous growth with General Purpose Technologies (GPTs) that captures two important historical stylized facts: First, from the beginning of mankind until today GPTs are arriving at an increasing frequency and, second, all GPTs heavily depended on previous technologies. In our model, the arrival of GPTs is endogenous and arises stochastically depending on the currently available applied knowledge stock. This way of endogenizing the arrival of new GPTs allows for a model which is more in tune with the historical reality than the existing GPT models.Schumpeterian growth; research and development; general purpose technologies

Long-term growth driven by a sequence of general purpose technologies

We present a Schumpterian model of endogenous growth with General Purpose Technologies (GPTs) that captures two important historical stylized facts: First, from the beginning of mankind until today GPTs are arriving at an increasing frequency and, second, all GPTs heavily depended on previous technologies. In our model, the arrival of GPTs is endogenous and arises stochastically depending on the currently available applied knowledge stock. This way of endogenizing the arrival of new GPTs allows for a model which is more in tune with the historical reality than the existing GPT models

Effect of the Matrix Metalloproteinase Inhibitor Doxycycline on Human Trace Fear Memory

Learning to predict threat is of adaptive importance, but aversive memory can also become disadvantageous and burdensome in clinical conditions such as posttraumatic stress disorder (PTSD). Pavlovian fear conditioning is a laboratory model of aversive memory and thought to rely on structural synaptic reconfiguration involving matrix metalloproteinase (MMP)9 signaling. It has recently been suggested that the MMP9-inhibiting antibiotic doxycycline, applied before acquisition training in humans, reduces fear memory retention after one week. This previous study used cued delay fear conditioning, in which predictors and outcomes overlap in time. However, temporal separation of predictors and outcomes is common in clinical conditions. Learning the association of temporally separated events requires a partly different neural circuitry, for which the role of MMP9 signaling is not yet known. Here, we investigate the impact of doxycycline on long-interval (15 s) trace fear conditioning in a randomized controlled trial with 101 (50 females) human participants. We find no impact of the drug in our preregistered analyses. Exploratorypost hocanalyses of memory retention suggested a serum level-dependent effect of doxycycline on trace fear memory retention. However, effect size to distinguish CS+/CS− in the placebo group turned out to be smaller than in previously used delay fear conditioning protocols, which limits the power of statistical tests. Our results suggest that doxycycline effect on trace fear conditioning in healthy individuals is smaller and less robust than anticipated, potentially limiting its clinical application potential

Citizen scientist monitoring accurately reveals nutrient pollution dynamics in Lake Tanganyika coastal waters

Several studies in Lake Tanganyika have effectively employed traditional methods to explore changes in water quality in open waters; however, coastal monitoring has been restricted and sporadic, relying on costly sample and analytical methods that require skilled technical staff. This study aims in validating citizen science water quality collected data (nitrate, phosphate and turbidity) with those collected and measured by professional scientists in the laboratory. A second objective of the study is to use citizen scientist data to identify the patterns of seasonal and spatial variations in nutrient conditions and forecast potential changes based on expected changes in population and climate (to 2050). The results showed that the concentrations of nitrate and phosphate measured by citizen scientists nearly matched those established by professional scientists, with overall accuracy of 91% and 74%, respectively. For total suspended solids measured by professional and turbidity measured by citizen scientists, results show that, using 14 NTU as a cut-off, citizen scientist measurements of Sec-chi tube depth to identify lake TSS below 7.0 mg/L showed an accuracy of 88%. In both laboratory and citizen scientist-based studies, all measured water quality variables were significantly higher during the wet season compared to the dry season. Climate factors were discovered to have a major impact on the likelihood of exceeding water quality restrictions in the next decades (2050), which could deteriorate lake conditions. Upscaling citizen science to more communities on the lake and other African Great Lakes would raise environmental awareness, inform management and mitigation activities, and aid long-term decision-making

Diazotrophic Cyanobacteria are Associated With a Low Nitrate Resupply to Surface Waters in Lake Tanganyika

In Lake Tanganyika, blooms of nitrogen-fixing (diazotrophic) cyanobacteria emerge, when the upper water column re-stratifies after a period of upwelling and convective mixing. During this seasonal transition, diazotrophic cyanobacteria exploit the abundant phosphate and fix nitrogen after other phytoplankton taxa have consumed the available nitrate. However, it remains less clear, which mechanisms favour diazotrophic cyanobacteria under more heavily stratified conditions with lower levels of excess phosphate and persistent nitrate-depletion. Here, we collected profiles of physicochemical parameters, nutrients and photo-pigments, as well as the medium- to large-sized phytoplankton community during two lake-wide cruises to elucidate to what extent the abundance of diazotrophic cyanobacteria in Lake Tanganyikamay be controlled by the nitrate resupply through the thermocline into the euphotic zone. At stations where nitrate was depleted, but phosphate remained available near the surface, high densities of diazotrophic cyanobacteria were associated with a low nitrate supply to surface waters. Our data provide first support for two conceptual scenarios, where the relative position of the thermocline and the euphotic depth may create a functional niche for diazotrophic cyanobacteria: when the upward transport of nitrate into the euphotic zone is reduced by a subjacent thermocline, diazotrophic cyanobacteria, comprising Dolichospermum and Anabaenopsis, are key players in the medium to large-sized phytoplankton community. By contrast, a thermocline located within the euphotic zone allows for a rapid vertical transport of nitrate for a thriving nitrate-assimilating phytoplankton community that evidently outcompetes diazotrophic cyanobacteria. This study highlights that, under nitrogen-depleted conditions, diazotrophic cyanobacteria can also grow in response to a reduced nutrient resupply to the productive surface waters

Patrones y factores impulsores de cambios en la calidad del agua asociados a embalses en los Andes tropicales

The Tropical Andes is a biodiversity hotspot facing pressure from planned and ongoing hydropower development. However, the effects of dams on river ecosystems of the region as mediated by physico-chemical changes to water quality are poorly known. Colombia is unique among its peers in South America for managing central public environmental databases, including surface water quality data sets associated with environmental monitoring of dams. To assess the relationship between hydropower and Colombian river conditions, we analyze monitoring data associated with 15 dams, focusing on oxygen availability, thermal regimes and sediment losses because these properties are influenced directly by river damming and impose fundamental constraints on the structure of downstream aquatic ecosystems. We find that most Colombian dams (7 of 10) seasonally reduce concentrations of total suspended solids by large percentages (50-99%) through sediment trapping. Most dams (8 of 15) also, via discharge of warm reservoir surface waters, seasonally increase river temperatures by 2 to 4˚C with respect to upstream conditions. A subset of four dams generates downstream hypoxia (<4 mg L-1) and water 2 to 5˚C colder than inflows—both processes driven by the turbination and discharge of cold and anoxic hypolimnetic waters during periods of reservoir stratification. Reliance on monitoring data likely leads us to under-detect impacts because many rivers are only sampled once or twice per year and cannot capture temporal shifts across seasons and days (i.e., in response to hydropeaking). Despite these blind spots, the monitoring data point to some opportunities for planners and hydropower companies to mitigate downstream ecological impacts. These findings highlight the importance of implementing environmental monitoring schemes associated with hydrologic infrastructure in developing countries.Los Andes tropicales son una zona de alta biodiversidad, que constantemente se enfrenta a la presión del desarrollo hidroeléctrico. Sin embargo, los efectos de los embalses en los ecosistemas fluviales de la regióninfluenciados por cambios fisicoquímicos en la calidad del agua son poco conocidos. Colombia es el único país en América del Sur que gestiona bases de datos ambientales públicos y centralizados, allí se incluyen conjuntos de datos sobre la calidad de aguas superficiales asociados a la vigilancia medioambiental de las represas. Para evaluar las relaciones entre las condiciones de los ríos en Colombia con relación a las centrales hidroeléctricas, analizamos los datos de monitoreo asociados con 15 represas, enfocándonos en la disponibilidad de oxígeno, el régimen térmico y la pérdida de sedimentos; ya que estas propiedades están influenciadas directamente por la construcción de represas en los ríos, e imponen restricciones fundamentales en la estructura de los ecosistemas acuáticos aguas abajo de la presa. Encontramos que en la mayoría de los embalses en Colombia (7 de 10) se reducen estacionalmente grandes porcentajes de las concentraciones de sólidos suspendidos totales (50-99%) debido a la captura de sedimentos. Adicionalmente, la mayoría de los embalses (8 de 15), a través de la descarga de aguas superficiales a mayor temperatura, aumentan estacionalmente las temperaturas del río (entre 2 y 4 °C) con respecto a las condiciones aguas arriba. Un subconjunto de cuatro represas genera hipoxia aguas abajo (<4 mg L-1), y aguas más frías que la de los flujos entrantes (entre 2 y 5 °C), ambos procesos impulsados por la turbinación y descarga de aguas hipolimnéticas frías y anóxicas durante los períodos de estratificación del embalse. Es probable que la dependencia de los datos de monitoreo nos lleve a subestimar los impactos, porque muchos de los ríos solo se monitorean una o dos veces al año y es posible detectar los cambios temporales entre las estaciones y los días (es decir, en respuesta al hydropeaking). A pesar de estos puntos ciegos, los datos de monitoreo representan algunas oportunidades para que los planificadores y las empresas hidroeléctricas mitiguen los impactos ecológicos río abajo. Estos hallazgos resaltan la importancia de implementar esquemas de seguimientos medioambientales asociados con la infraestructura hidrológica en los países en vía de desarrollo

Smoking trends and health equity in Switzerland between 1992 and 2017: dependence of smoking prevalence on educational level and social determinants

BackgroundSwitzerland ranks among the top three healthcare systems in the world with regards to healthcare access, suggesting a high degree of health equity. However, Switzerland has few preventive strategies against smoking abuse. The aim of this study is to clarify whether educational level and citizenship status have an influence on the prevalence of smoking in Switzerland and whether there is health inequity related to a lack of preventive strategies.MethodsWe based our analysis on publicly available health data published in the Swiss government's Swiss health survey (1992–2017). We compared the prevalence of smoking across the years and correlated these data with levels of educational attainment, citizenship status and age.ResultsA continuous significant decline in smokers is observed in the highest education group (TERT). Over time, prevalence was reduced from 29% in 1992 to 23% in 2017 (p < 0.001). The intermediate-level educational group (SEK 2) showed smaller but also significant decline on a 0.05 sigificance level over the same period, from 31% to 29% (p = 0.003). The lowest educational group showed a nonsignificant decline from 28% to 27% (p = 0.6). The population who holds Swiss citizenship showed a decrease in smoking from 28% to 26% within the time frame (p < 0.001). People without Swiss citizenship had a much higher prevalence of smokers, at 38% in 1992 and declining to 32% in 2017 (p < 0.001). All cohorts from age 15 to age 64 have a far higher prevalence of smokers than cohorts at an older age, with the highest prevalence in the 25–34 age group.ConclusionIn Switzerland, individuals with lower levels of education and non-Swiss populations are more susceptible to health risk of smoking. This is despite the existence of a high-quality healthcare system that has nevertheless failed to negated health inequities

Non-invasive Predictors of Human Cortical Bone Mechanical Properties: T2-Discriminated 1H NMR Compared with High Resolution X-ray

Recent advancements in magnetic resonance imaging (MRI) have enabled clinical imaging of human cortical bone, providing a potentially powerful new means for assessing bone health with molecular-scale sensitivities unavailable to conventional X-ray-based diagnostics. To this end, 1H nuclear magnetic resonance (NMR) and high-resolution X-ray signals from human cortical bone samples were correlated with mechanical properties of bone. Results showed that 1H NMR signals were better predictors of yield stress, peak stress, and pre-yield toughness than were the X-ray derived signals. These 1H NMR signals can, in principle, be extracted from clinical MRI, thus offering the potential for improved clinical assessment of fracture risk