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1. A mathematical overview and some applications of gear design

   Elisabetta A. Matsumoto and Henry Segerman (November 2023, Proceedings of symposia in applied mathematics)

   Maria Trnkova and Andrew Yarmola (Ed.)

   In this paper we give a brief overview of the geometry of involute gears, from a mathematical more than an engineering perspective. We also list some of the many variant geared mechanisms and discuss some of our 3D printed mechanisms. 

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2. A Magnetically Geared Lead Screw Without Translator Skewing

   https://doi.org/10.1109/ECCE.2018.8557751  

   Kouhshahi, M. Bahrami; Bird, J. Z.; Jannsen, A.; Kadel, J.; Williams, W. (September 2018, 2018 IEEE Energy Conversion Congress and Exposition (ECCE))

   A magnetically geared lead screw is able to convert high-speed rotation to low-speed translation via magnetic gearing. In this paper a new type of magnetically geared lead screw is presented that uses translator rings without any skewing. The magnetic gearing is accomplished by utilizing an inner rotor with helically skewed magnets and an outer cylinder with a skewed flux focusing magnet arrangement. The operating characteristics and an experimental prototype are presented. 

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3. Predicting transcriptional outcomes of novel multigene perturbations with GEARS

   https://doi.org/10.1038/s41587-023-01905-6  

   Roohani, Yusuf; Huang, Kexin; Leskovec, Jure (August 2023, Nature Biotechnology)

   Abstract Understanding cellular responses to genetic perturbation is central to numerous biomedical applications, from identifying genetic interactions involved in cancer to developing methods for regenerative medicine. However, the combinatorial explosion in the number of possible multigene perturbations severely limits experimental interrogation. Here, we present graph-enhanced gene activation and repression simulator (GEARS), a method that integrates deep learning with a knowledge graph of gene–gene relationships to predict transcriptional responses to both single and multigene perturbations using single-cell RNA-sequencing data from perturbational screens. GEARS is able to predict outcomes of perturbing combinations consisting of genes that were never experimentally perturbed. GEARS exhibited 40% higher precision than existing approaches in predicting four distinct genetic interaction subtypes in a combinatorial perturbation screen and identified the strongest interactions twice as well as prior approaches. Overall, GEARS can predict phenotypically distinct effects of multigene perturbations and thus guide the design of perturbational experiments. 

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4. Can aromaticity be a kinetic trap? Example of mechanically interlocked aromatic [2-5]catenanes built from cyclo[18]carbon

   https://doi.org/10.1039/C9CC09483K  

   Fedik, Nikita; Kulichenko, Maksim; Steglenko, Dmitriy; Boldyrev, Alexander I. (March 2020, Chemical Communications)

   The unusual stability of cyclo[18]carbon arising from its aromaticity might be used to provide the kinetic trapping needed in the design of interlocked systems. The kinetic barrier separating the interlocked rings and the chemically bonded complex is about 30 kcal mol −1 . In addition, the rings can slide freely, which is a promising property for the design of molecular gears and motors. 

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5. TESTING TRANSPARENCY

   Daniels, Brigham; Buntaine, Mark T.; Bangerter, Tanner (March 2020, Northwestern University law review)

   In modern democracies, governmental transparency is thought to have great value. When it comes to addressing administrative corruption and mismanagement, many would agree with Justice Brandeis’s observation that sunlight is the best disinfectant. Beyond this, many credit transparency with enabling meaningful citizen participation. But even though transparency appears highly correlated with successful governance in developed democracies, assumptions about administrative transparency have remained empirically untested. Testing effects of transparency would prove particularly helpful in developing democracies where transparency norms have not taken hold or only have done so slowly. In these contexts, does administrative transparency really create the sorts of benefits attributed to it? Transparency might grease the gears of developed democracies, but what good is grease when many of the gears seem to be broken or missing entirely? This Article presents empirical results from a first-of-its-kind field study that tested two major promises of administrative transparency in a developing democracy: that transparency increases public participation in government affairs and that it increases government accountability. To test these hypotheses, we used two randomized controlled trials. Surprisingly, we found transparency had no significant effect in almost any of our quantitative measurements, although our qualitative results suggested that when transparency interventions exposed corruption, some limited oversight could result. Our findings are particularly significant for developing democracies and show, at least in this context, that Justice Brandeis may have oversold the cleansing effects of transparency. A few rays of transparency shining light on government action do not disinfect the system and cure government corruption and mismanagement. Once corruption and mismanagement are identified, it takes effective government institutions and action from civil society to successfully act as a disinfectant. 

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