TrkA Signalling and Parkinson’s Dementia

Cognitive impairment and dementia are the most frequently occurring nonmotor symptoms in Parkinson’s disease (PD), yet these symptoms are mostly overlooked and are not diagnosed and treated exceptionally like the cardinal motor symptoms in clinical practice. It is only in the late twentieth century that dementia has been recognized as a major clinical manifestation in PD. The possible mechanisms that cause dementia are complex with different patterns of cognitive behavior that disrupt the patient’s quality of life. It is preeminently considered that the cholinergic denervation in the basal forebrain region mediates dementia in PD. So far, dopamine-based therapy is the key objective in the treatment of PD and the nonmotor symptoms are mostly neglected. Interestingly, the loss of Tyrosine kinase receptor-A (TrkA) signaling in basal forebrain results in neuronal atrophy, which precedes cholinergic denervation and cognitive impairment. Nerve Growth Factor (NGF) binds to TrkA receptors, inducing a cascade of events like PI-3Kinase/Akt and MAPK signaling pathways that render cholinergic degeneration and upregulate the choline acetyltransferase activity and neuronal differentiation. Hence, TrkA receptor activation by small molecules might attenuate the dementia symptoms associated with PD, and may be targeted as a novel treatment strategy along with regular clinical agents

iGEM: a model system for team science and innovation

Teams are a primary source of innovation in science and technology. Rather than examining the lone genius, scholarly and policy attention has shifted to understanding how team interactions produce new and useful ideas. Yet the organizational roots of innovation remain unclear, in part because of the limitations of current data. This paper introduces the international Genetically Engineered Machine (iGEM) competition, a model system for studying team science and innovation. By combining digital laboratory notebooks with performance data from 2,406 teams over multiple years of participation, we reveal shared dynamical and organizational patterns across teams and identify features associated with team performance and success. This dataset makes visible organizational behavior that is typically hidden, and thus understudied, creating new opportunities for the science of science and innovation.Comment: 78 pages including SI, 7 figures, 18 SI figure

Geometrical guidance and trapping transition of human sperm cells

The guidance of human sperm cells under confinement in quasi-2D microchambers is investigated using a purely physical method to control their distribution. Transport property measurements and simulations are performed with diluted sperm populations, for which effects of geometrical guidance and concentration are studied in detail. In particular, a trapping transition at convex angular wall features is identified and analyzed. We also show that highly efficient microratchets can be fabricated by using curved asymmetric obstacles to take advantage of the spermatozoa specific swimming strategy.publishedVersionFil: Guidobaldi, Héctor Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina.Fil: Guidobaldi, Héctor Alejandro. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Biología Celular y Molecular; Argentina.Fil: Jeyaram, Y. Katholieke Universiteit Leuven. Institute for Nanoscale Physics and Chemistry; Bélgica.Fil: Berdakin, Ivan. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Berdakin, Ivan. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Moshchalkov, V. V. Katholieke Universiteit Leuven. Institute for Nanoscale Physics and Chemistry; Bélgica.Fil: Condat, Carlos Alberto. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Condat, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Marconi, Verónica Iris. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Marconi, Verónica Iris. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Giojalas, Laura Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina.Fil: Giojalas, Laura Cecilia. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Biología Celular y Molecular ; Argentina.Fil: Silhanek, Alejandro V. Université de Liège. Faculté des Sciences. Departement de Physique; Bélgica.Biofísic

Cropland Carbon Uptake Delayed and Reduced by 2019 Midwest Floods

While large‐scale floods directly impact human lives and infrastructures, they also profoundly impact agricultural productivity. New satellite observations of vegetation activity and atmospheric CO₂ offer the opportunity to quantify the effects of such extreme events on cropland carbon sequestration. Widespread flooding during spring and early summer 2019 induced conditions that delayed crop planting across the U.S. Midwest. As a result, satellite observations of solar‐induced chlorophyll fluorescence from TROPOspheric Monitoring Instrument and Orbiting Carbon Observatory reveal a 16‐day shift in the seasonal cycle of photosynthesis relative to 2018, along with a 15% lower peak value. We estimate a reduction of 0.21 PgC in cropland gross primary productivity in June and July, partially compensated in August and September (+0.14 PgC). The extension of the 2019 growing season into late September is likely to have benefited from increased water availability and late‐season temperature. Ultimately, this change is predicted to reduce the crop productivity in the Midwest Corn/Soy belt by ~15% compared to 2018. Using an atmospheric transport model, we show that a decline of ~0.1 PgC in the net carbon uptake during June and July is consistent with observed CO₂ enhancements of up to 10 ppm in the midday boundary layer from Atmospheric Carbon and Transport‐America aircraft and over 3 ppm in column‐averaged dry‐air mole fractions from Orbiting Carbon Observatory. This study quantifies the impact of floods on cropland productivity and demonstrates the potential of combining solar‐induced chlorophyll fluorescence with atmospheric CO₂ observations to monitor regional carbon flux anomalies

Influence of swimming strategy on microorganism separation by asymmetric obstacles

It has been shown that a nanoliter chamber separated by a wall of asymmetric obstacles can lead to an inhomogeneous distribution of self-propelled microorganisms. Although it is well established that this rectification effect arises from the interaction between the swimmers and the noncentrosymmetric pillars, here we demonstrate numerically that its efficiency is strongly dependent on the detailed dynamics of the individual microorganism. In particular, for the case of run-and-tumble dynamics, the distribution of run lengths, the rotational diffusion, and the partial preservation of run orientation memory through a tumble are important factors when computing the rectification efficiency. In addition, we optimize the geometrical dimensions of the asymmetric pillars in order to maximize the swimmer concentration and we illustrate how it can be used for sorting by swimming strategy in a long array of parallel obstacles