Preprint Version Research Articles

Leech‐Inspired Shape‐Encodable Liquid Metal Robots for Reconfigurable Circuit Welding and Transient Electronics

Deformability and self‐adaptability are important for soft robots to deal with uncertain and varying situations and environments during movement and navigation. Droplet‐based robots are great candidates to travel inside narrow and constrained spaces without damaging the interfaces due to their extreme deformability and liquid nature, which enables smooth contact between robots and target spaces. Here, magnetic liquid metal droplet robots, comprising liquid metal and carbonyl iron, that can perform reversible telescopic deformation, bending, and on‐demand locomotion are proposed. The magnetic liquid‐metal‐based robots can perform on‐demand and reversible coalescence and splitting by intricately applying magnetic fields. Importantly, the liquid metal robot can perform phase transition to fix the desired shape after programmable shape encoding. The liquid‐metal‐based soft robots can serve as dynamic and recyclable switches for complex circuits, and are capable of repairing damaged sections of microcircuits by remote actuation, controllable coalescence, and on‐demand circuit welding. This technology provides a new application scenario of droplet‐based soft robots for on‐demand circuit welding and transient recyclable electronics. A preprint version of the article can be found at: https://www.authorea.com/doi/full/10.22541/au.165167005.56125584.

More discussion of minimalist species descriptions and clarifying some misconceptions contained in Meier et al. 2021.

This is a response to a preprint version of "A re-analysis of the data in Sharkey et al.'s (2021) minimalist revision reveals that BINs do not deserve names, but BOLD Systems needs a stronger commitment to open science", https://www.biorxiv.org/content/10.1101/2021.04.28.441626v2. Meier et al. strongly criticized Sharkey et al.'s publication in which 403 new species were deliberately minimally described, based primarily on COI barcode sequence data. Here we respond to these criticisms. The following points are made: 1) Sharkey et al. did not equate BINs with species, as demonstrated in several examples in which multiple species were found to be in single BINs. 2) We reiterate that BINs were used as a preliminary sorting tool, just as preliminary morphological identification commonly sorts specimens based on color and size into unit trays; despite BINs and species concepts matching well over 90% of species, this matching does not equate to equality. 3) Consensus barcodes were used only to provide a diagnosis to conform to the rules of the International Code of Zoological Nomenclature just as consensus morphological diagnoses are. The barcode of a holotype is definitive and simply part of its cellular morphology. 4) Minimalist revisions will facilitate and accelerate future taxonomic research, not hinder it. 5) We refute the claim that the BOLD sequences of Plesiocoelusvanachterbergi are pseudogenes and demonstrate that they simply represent a frameshift mutation. 6) We reassert our observation that morphological evidence alone is insufficient to recognize species within species-rich higher taxa and that its usefulness lies in character states that are congruent with molecular data. 7) We show that in the cases in which COI barcodes code for the same amino acids in different putative species, data from morphology, host specificity, and other ecological traits reaffirm their utility as indicators of genetically distinct lineages.

Spatiotemporally Programmable Surfaces via Viscoelastic Shell Snapping

Many species can dynamically alter their skin textures to enhance their motility and survivability. Despite the enormous efforts on designing bio‐inspired materials with tunable surface textures, developing spatiotemporally programmable and reconfigurable textural morphing without complex control remains challenging. Herein, a design strategy is proposed to achieve surfaces with such properties. The surfaces comprise an array of unit cells with broadly tailored temporal responses. By arranging the unit cells differently, the surfaces can exhibit various spatiotemporal responses, which can be easily reconfigured by disassembling and rearranging the unit cells. Specifically, viscoelastic shells as the unit cells is adopted, which can be pneumatically actuated to a concave state, and recover the initial convex state sometime after the load is removed. It is shown computationally and experimentally that the recovery time can be widely tuned by the geometry and material viscoelasticity of the shells. By assembling such shells with different recovery times, surfaces with pre‐programmed spatiotemporal textural morphing under simple pneumatic actuation is built, and temporal evolution of patterns, such as digit numbers and emoji, and spatiotemporal control of friction are demonstrated. This work opens up new avenues in designing spatiotemporal morphing surfaces that could be employed for programming mechanical, optical, and electrical properties. A preprint version of the article can be found at: https://www.authorea.com/doi/full/10.22541/au.164020946.62560710.

WisDM Green: Harnessing Artificial Intelligence to Design and Prioritize Compound Combinations in Peat Moss for Sustainable Farming Applications

The substantial increase in global population and climate change, among other factors, have led to global food security and supply chain challenges. The United Nations has laid out an agenda to sustainably achieve zero hunger by 2030 as one of its sustainable development goals. However, sustainably achieving improved food yield has become a challenge as excessive use of fertilizers has also led to adverse environmental impact. To address the aforementioned challenges, WisDM Green, an artificial intelligence (AI)‐based platform that aims to pinpoint and prioritize compound (e.g., biostimulants) combinations in peat moss, is harnessed to sustainably improve the yield of Amaranthus cruentus (red spinach). In this proof‐of‐concept study, from a pool of eight compounds, WisDM Green‐pinpointed combinations (6‐benzylaminopurine/ethylenediaminetetraacetic acid iron (III) (6‐BAP/EDTA‐Fe) and humic acid/seaweed extract (HA/SWE)) achieved 26.34 ± 15.80 and 33.59 ± 14.60 increase in %Yield, respectively. The study also indicates that compound combinations may exhibit concentration‐dependent synergies and thus, properly adjusting the concentration ratios of combinations may further improve plant yield in the context of sustainable farming. An interactive preprint version of the article can be found at: https://www.authorea.com/doi/full/10.22541/au.165244695.56681780.

An Individually Controlled Multitined Expandable Electrode Using Active Cannula‐Based Shape Morphing for On‐Demand Conformal Radiofrequency Ablation Lesions

Being minimally invasive and highly effective, radiofrequency ablation (RFA) is widely used for small‐sized malignant tumor treatment. However, in clinical practice, a large number of tumors are found in irregular shape, while the current RFA devices are hard to control the morphologic appearance of RFA lesions on demand, which usually ends up with unnecessarily excessive tissue ablation and subsequently often brings irreversible damage to the organs’ functions. Herein, active cannulas for each of the individually controlled subelectrodes to achieve an on‐demand shape morphing and thus conformal RFA lesion are introduced. The target shape as well as the length of inserted subelectrodes can be precisely controlled by tuning the active stylets and cannulas. What's more, owing to independent movement and energy control of each subelectrodes, the electrode is shown to be not only efficient enough to accomplish accurate trajectory control to target tissue in a single insertion, but also adaptive enough to ablate target tissues with diverse morphologic appearances and locations. On‐demand conformal ablation of target tissue is demonstrated as well under the guidance of ultrasound imaging with the device. Potentially, the RFA electrode is a promising minimally invasive treatment of malignant tumors in future clinical practice. An interactive preprint version of the article can be found at: https://www.authorea.com/doi/full/10.22541/au.164019293.38729522.

An Open Platform for High‐Resolution Light‐Based Control of Microscopic Collectives

Engineering microscopic collectives of cells or microrobots is challenging due to the often limited capabilities of the individual agents, the inability to reliably program their motion and local interactions, and difficulties visualizing their behaviors. Herein, a low‐cost, modular, and open‐source Dynamic Optical MicroEnvironment (DOME) is presented with the ability to augment microagent capabilities, and drive collective behaviors using light. The DOME offers an accessible means to study complex multicellular phenomena and implement de‐novo microswarms with desired functionalities. An interactive preprint version of the article can be found at: https://www.authorea.com/doi/full/10.22541/au.164191998.84940186.

School Integration Limits the Ability of Local Norms to Diversify Gifted Programs: A Mathematical Analysis with Implications Related to the Achievement Gap

Experts within gifted education have advocated for the use of local norms when selecting students for gifted programs, instead of national-level norms. Local norms compare students to their immediate peers to identify gifted students and are believed to produce a more diverse gifted program. However, district integration limits the ability of local norms to diversify gifted programs, a fact that has been almost completely overlooked in gifted education scholarship. Through a simplified example, we show that local building-level norms are best at diversifying gifted programs when schools are highly segregated. Conversely, when achievement gaps are present and a uniform admissions cutoff is applied, building-level norms in highly integrated schools produce highly segregated gifted programs. In short, the use of building-level local norms trades one form of segregation for another. Implications and recommendations for gifted education and beyond are explored. A preprint version of this article is available at https://psyarxiv.com/nemch/.

Pre2Pub-Tracking the Path From Preprint to Journal Article: Algorithm Development and Validation.

BackgroundThe current COVID-19 crisis underscores the importance of preprints, as they allow for rapid communication of research results without delay in review. To fully integrate this type of publication into library information systems, we developed preview: a publicly available, central search engine for COVID-19–related preprints, which clearly distinguishes this source from peer-reviewed publications. The relationship between the preprint version and its corresponding journal version should be stored as metadata in both versions so that duplicates can be easily identified and information overload for researchers is reduced.ObjectiveIn this work, we investigated the extent to which the relationship information between preprint and corresponding journal publication is present in the published metadata, how it can be further completed, and how it can be used in preVIEW to identify already republished preprints and filter those duplicates in search results.MethodsWe first analyzed the information content available at the preprint servers themselves and the information that can be retrieved via Crossref. Moreover, we developed the algorithm Pre2Pub to find the corresponding reviewed article for each preprint. We integrated the results of those different resources into our search engine preVIEW, presented the information in the result set overview, and added filter options accordingly.ResultsPreprints have found their place in publication workflows; however, the link from a preprint to its corresponding journal publication is not completely covered in the metadata of the preprint servers or in Crossref. Our algorithm Pre2Pub is able to find approximately 16% more related journal articles with a precision of 99.27%. We also integrate this information in a transparent way within preVIEW so that researchers can use it in their search.ConclusionsRelationships between the preprint version and its journal version is valuable information that can help researchers finding only previously unknown information in preprints. As long as there is no transparent and complete way to store this relationship in metadata, the Pre2Pub algorithm is a suitable extension to retrieve this information.

Robotic Pill for Biomarker and Fluid Sampling in the Gastrointestinal Tract

Developing on‐site biomarker enrichment platforms could help to improve the diagnosis of gastrointestinal (GI) tract diseases at early stages. Medical procedures, such as colonoscopies and imaging techniques, are used to diagnose a disease, but are not easily accessible for repeat measurements. In contrast, liquid biopsies, e.g., blood, urine, or fecal samples, have become important sampling strategies to identify health concerns. Herein, a robotic pill is designed for collecting relevant biomarkers from the GI tract over prolonged sampling periods. The robotic pill is comprised of a magnetic core for locomotion, a delayed gate mechanism that controls sampling location based on changes in its environment, and an enrichment module that traps biomarkers in an absorbent matrix while enabling biofluid to pass through the chamber. The robotic pill was assessed to sample microparticles, proteins, and bacteria from the solution. Moreover, the robotic pill was capable of directed locomotion in complex environments and docking in a targeted region against fluid flow. The utilization of an untethered robotic sampling system could provide a tool to investigate aspects of disease initiation and progression for early diagnosis and therapy monitoring. A preprint version of the article can be found at: https://www.authorea.com/doi/full/10.22541/au.164458092.26571169.

Development of Self‐Folded Corrugated Structures Using Automatic Origami Technique by Inkjet Printing

The origami technique realizes unique mechanical properties of sheet materials without additional parts. Herein, a self‐folded corrugated structure (SCS) is developed based on the reinforcing properties of the origami technique. The corrugated structures are used as the core materials for a high‐strength, open‐channel sandwich structure. Research on self‐folded core materials is scarce; thus, a design concept is proposed, and the mechanical properties of the SCS are evaluated. First, the structural parameters of the SCS fabricated by changing the printing parameters (e.g., linewidth and number of lines/creases), to derive the structural model, are determined. The model facilitates the design of an SCS with the desired structure. Thereafter, the mechanical properties of the SCSs are evaluated by conducting three‐point bending tests to determine the essential design parameters corresponding to high stiffness. Moreover, SCSs can be stacked without occupying space, thus leading to improved strength. These SCSs fabricated using self‐folding paper by inkjet printing are low cost and ecofriendly. Moreover, they are specialized for rapid design and fabrication, depending on the application. Herein, the use of SCS as a novel smart core because it exhibits high transportation efficiency and stiffness without additional components is proposed. An interactive preprint version of the article can be found at: https://www.authorea.com/doi/full/10.22541/au.164915946.65764739.

Artificial Multisensory Neurons with Fused Haptic and Temperature Perception for Multimodal In‐Sensor Computing

The human receives and transmits various information from the outside world through different sensory systems. The sensory neurons integrate various sensory inputs into a synthetical perception to monitor complex environments, and this fundamentally determines the way how we perceive the world. Developing multifunctional artificial sensory elements that can integrate multisensory perception plays a vital role in future intelligent perception systems, whereas prior spiking neurons reported can only handle single‐mode physical signals. Herein, a bioinspired haptic‐temperature fusion spiking neuron based upon a serial connection of piezoresistive sensor and VO2 volatile memristor is presented. The artificial sensory neuron is capable of detecting and encoding pressure and temperature inputs based on the voltage dividing effect and the intrinsic thermal sensitivity of metal–insulator transition in VO2. Recognition of Braille characters is achieved through multiple piezoresistive sensors, taking advantage of the spatial integration capabilities of such spiking neurons. Notably, the traditionally separate haptic and temperature signals can be fused physically in the sensory neuron when synchronizing the two sensory cues, which is able to recognize multimodal haptic/temperature patterns. The artificial multisensory neuron thus provides a promising approach toward e‐skin, neurorobotics, and human–machine interaction technologies. A preprint version of the article can be found at: https://www.authorea.com/doi/full/10.22541/au.164668806.60849882.

Lhx2 in germ cells suppresses endothelial cell migration in the developing ovary

LIM-homeobox genes play multiple roles in developmental processes, but their roles in gonad development are not completely understood. Herein, we report that Lhx2, Ils2, Lmx1a, and Lmx1b are expressed in a sexually dimorphic manner in mouse, rat, and human gonads during sex determination. Amongst these, Lhx2 has female biased expression in the developing gonads of species with environmental and genetic modes of sex determination. Single-cell RNAseq analysis revealed that Lhx2 is exclusively expressed in the germ cells of the developing mouse ovaries. To elucidate the roles of Lhx2 in the germ cells, we analyzed the phenotypes of Lhx2 knockout XX gonads. While the gonads developed appropriately in Lhx2 knockout mice and the somatic cells were correctly specified in the developing ovaries, transcriptome analysis revealed enrichment of genes in the angiogenesis pathway. There was an elevated expression of several pro-angiogenic factors in the Lhx2 knockout ovaries. The elevated expression of pro-angiogenic factors was associated with an increase in numbers of endothelial cells in the Lhx2−/− ovaries at E13.5. Gonad recombination assays revealed that the increased numbers of endothelial cells in the XX gonads in absence of Lhx2 was due to ectopic migration of endothelial cells in a cell non-autonomous manner. We also found that, there was increased expression of several endothelial cell-enriched male-biased genes in Lhx2 knockout ovaries. Also, in absence of Lhx2, the migrated endothelial cells formed an angiogenic network similar to that of the wild type testis, although the coelomic blood vessel did not form. Together, our results suggest that Lhx2 in the germ cells is required to suppress vascularization in the developing ovary. These results suggest a need to explore the roles of germ cells in the control of vascularization in developing gonads. Preprint version of the article is available on BioRxiv at https://doi.org/10.1101/2022.03.07.483280.

A Wirelessly Controlled Shape‐Memory Alloy‐Based Bistable Metal Swimming Device

Shape memory Nitinol has long been used for actuation. However, utilizing Nitinol to fabricate novel devices for various applications is a challenge, but has shown incredible promise and impacts. Bistable metal strips are widely adopted for shape morphing purposes (primarily in kid's toys, e.g., snap bracelets) due to their easy and robust transformation between two states. Herein, Nitinol shape memory alloy and bistable metal strip are combined to fabricate a swimming actuator with both slow moving and fast snapping capability, akin to an octopus swimming slowly in water, but quickly moving upon encountering a threat. The actuator developed here can also swim in multiple directions, all controlled by a wireless module. Furthermore, it is demonstrated that an onboard sensor can be incorporated for potential environmental monitoring applications. The fact that the device developed here has no mechanical parts, makes this an interesting potential alternative to more expensive, and energy consuming boats. A preprint version of the article can be found at: https://www.authorea.com/doi/full/10.22541/au.164199106.60208565.

Stochastic Jumping Robots for Large‐Scale Environmental Sensing

Single‐use jumping robots that are mass‐producible and biodegradable could be quickly released for environmental sensing applications. Such robots would be pre‐loaded to perform a set number of jumps, in random directions and with random distances, removing the need for onboard energy and computation. Stochastic jumpers build on embodied randomness and large‐scale deployments to perform useful work. This paper introduces simulation results showing how to construct a large group of stochastic jumpers to perform environmental sensing, and the first demonstration of robot prototypes that can perform a set number of sequential jumps, have full‐body sensing, and are well suited to be made biodegradable. An interactive preprint version of the article can be found at: https://www.authorea.com/doi/full/10.22541/au.163525369.97561426.

Sales of Over-the-Counter Products Containing Codeine in 31 Countries, 2013-2019: A Retrospective Observational Study.

Opioid prescribing trends have been investigated in many countries. However, the patterns of over-the-counter purchases of opioids without a prescription, such as codeine combinations, are mostly unknown. We aimed to assess national sales and expenditure trends of over-the-counter codeine-containing products purchased in countries with available data over 6 years. We conducted a retrospective observational study using electronic point-of-sale data from the human data science company, IQVIA, for countries that had such data, including Argentina, Belgium, Brazil, Bulgaria, Canada, Croatia, Estonia, Finland, France, Germany, Greece, Ireland, Italy, Japan, Latvia, Lithuania, Mexico, the Netherlands, Poland, Portugal, Romania, Russia, Serbia, Slovakia, Slovenia, South Africa, Spain, Switzerland, Thailand, the UK, and the USA. We calculated annual mean sales (dosage units/1000 population) and public expenditure (£/1000 population) for each country between April 2013 and March 2019 and adjusted for data coverage reported by IQVIA. We quantified changes over time and the types of products sold. In total, 31.5 billion dosage units (adjusted: 42.8 billion dosage units) of codeine, costing £2.55 billion (adjusted: £3.68 billion), were sold over the counter in 31 countries between April 2013 and March 2019. Total adjusted sales increased by 11% (from 3911 dosage units/1000 population in 2013 to 4358 in 2019) and adjusted public expenditure increased by 72% (from £263/1000 in 2013 to £451/1000 in 2019). Sales were not equally distributed; South Africa sold the most (36 mean dosage units/person), followed by Ireland (30 mean dosage units/person), France (20 mean dosage units/person), the UK (17.2 mean dosage units/person), and Latvia (16.8 mean dosage units/person). Types of products (n = 569) and formulations (n = 12) sold varied. In many parts of the world, substantial numbers of people may be purchasing and consuming codeine in over-the-counter products. Clinicians should ask patients about their use of over-the-counter products, and public health measures are required to improve the collection of sales data and the safety of such products. STUDY PROTOCOL PRE-REGISTRATION: https://osf.io/ay4mc . The pre-print version of this work is available on medRxiv: https://doi.org/10.1101/2021.04.21.21255888 .

Magnetic Miniature Actuators with Six‐Degrees‐of‐Freedom Multimodal Soft‐Bodied Locomotion

Magnetic miniature robots (MMRs) are mobile actuators that can exploit their size to noninvasively access highly confined, enclosed spaces. By leveraging on such unique abilities, MMRs have great prospects to transform robotics, biomedicine, and materials science. As having high dexterity is critical for MMRs to enable their targeted applications, existing MMRs have developed numerous soft‐bodied gaits to locomote in various environments. However, there exist two critical limitations that have severely restricted their dexterity: 1) MMRs capable of multimodal soft‐bodied locomotion have only demonstrated five‐degrees‐of‐freedom (five‐DOF) motions because the sixth‐DOF rotation about their net magnetic moment axis is uncontrollable; 2) six‐DOF MMRs have only realized one mode of soft‐bodied, swimming locomotion. Herein, a six‐DOF MMR is proposed that can execute seven modes of soft‐bodied locomotion and perform 3D pick‐and‐place operations. By optimizing its harmonic magnetization profile, the MMR can produce 1.41–63.9‐fold larger sixth‐DOF torque than existing MMRs with similar profiles, without compromising their traditional five‐DOF actuation capabilities. The proposed MMR demonstrates unprecedented dexterity: it can jump through narrow slots to reach higher grounds; use precise orientation control to roll, two‐anchor crawl, and swim across tight openings with strict shape constraints; and perform undulating crawling across three different planes in convoluted channels. An interactive preprint version of the article can be found at: https://www.authorea.com/doi/full/10.22541/au.164087652.25227465.

Human‐Like Interactive Behavior Generation for Autonomous Vehicles: A Bayesian Game‐Theoretic Approach with Turing Test

Interacting with surrounding road users is a key feature of autonomous vehicles and is critical for their intelligence testing. Existing interaction modalities in autonomous vehicle simulation and testing are not sufficiently smart, and they barely reflect human‐like behaviors in real‐world driving scenarios. Therefore, a novel hierarchical game‐theoretical framework is presented to represent naturalistic multimodal interactions among road users during simulation and testing, which is subsequently validated by the Turing test. Given that human drivers have no access to the complete information of the surrounding road users, the Bayesian game theory is used to model the decision‐making process. Next, a probing behavior is generated by the proposed game‐theoretic model, and is further applied to control the vehicle via the Markov chain. The proposed method is tested through a series of experiments and compared with existing approaches. In addition, Turing tests are conducted to quantify the human‐likeness of the proposed algorithm. The experimental results show that the proposed Bayesian game‐theoretic framework can effectively generate representative scenes of human‐like decision‐making during autonomous vehicle interactions, demonstrating its feasibility and effectiveness. An interactive preprint version of the article can be found at: https://www.authorea.com/doi/full/10.22541/au.163482630.00283278.

Heat and The Energy Transition: Pre Print Version

Heat and The Energy Transition: Pre Print Version

Pursuing Intelligent Behavior in Cyber−Physical Systems by Lightweight Diagnosis

Intelligence in its decisions is a trait that people have grown to expect from a cyber−physical system, in particular that it makes the right choices at runtime, that is, those that allow it to fulfill its tasks, even in case of faults or unexpected interactions with its environment. Analyzing how to continuously achieve the currently desired (and possibly continuously changing) goals and adapting its behavior to reach these goals is undoubtedly a serious challenge. This becomes even more challenging if the atomic actions a system can implement become unreliable due to faulty components or some exogenous event out of its control. Herein, a solution for the presented challenge is proposed. In particular, it is shown how to adopt a lightweight diagnosis concept to cope with such situations. The approach is based on rules coupled with means for rule selection that is based on previous information regarding success or failure of rule executions. Furthermore, Java‐based framework of the lightweight diagnosis concept is presented, and the results obtained from an experimental evaluation considering several application scenarios are discussed. At the end, a qualitative comparison with other related approaches that should help the readers decide which approach works best for them is presented. An interactive preprint version of the article can be found here: https://www.authorea.com/doi/full/10.22541/au.163578445.51350502.

Preprint articles as a tool for teaching data analysis and scientific communication.

The skill of analyzing and interpreting research data is central to the scientific process, yet it is one of the hardest skills for students to master. While instructors can coach students through the analysis of data that they have either generated themselves or obtained from published articles, the burgeoning availability of preprint articles provides a new potential pedagogical tool. We developed a new method in which students use a cognitive apprenticeship model to uncover how experts analyzed a paper and compare the professional's cognitive approach to their own. Specifically, students first critique research data themselves and then identify changes between the preprint and final versions of the paper that were likely the results of peer review. From this activity, students reported diverse insights into the processes of data presentation, peer review, and scientific publishing. Analysis of preprint articles is therefore a valuable new tool to strengthen students' information literacy and understanding of the process of science.