bluuebunny/crossref_metadata_2025 huggingface dataset:
Neuro‐fuzzy Elman wavelet control for nonlinear uncertain systems with fuzzy input and unknown fuzzy disturbances: Application to robotics
Authors: Kumar Rahul , Singh Uday Pratap , Bali Arun , Jain Sanjeev
Published: September 2022

Keeping into view the irregular existence of uncertainties and disturbances in nonlinear systems, a novel adaptive control scheme based on neuro‐fuzzy Elman wavelet neural network (NFEWNN) has been proposed in this work which is capable of accurately modeling system uncertainties. In addition to this, an improvement in an evolutionary algorithm named particle swarm optimization has also been introduced to optimize the initial parameters of the controller. Uncertain non‐linear discrete‐time systems in the non‐strict feedback form with unknown disturbances are taken into consideration. This work aims to design an efficient adaptive control scheme for the proposed systems in the case of fuzzy input and fuzzy external disturbance which makes the control of the system more complex and difficult. The proposed NFEWNN control scheme is capable of tracking the desired trajectory successfully along with accurately modeling system uncertainties with high computational power, low computational burden, and rapid convergence rate. The stability of the controller has been proved using Lyapunov theory and guaranteed convergence of the controller is proved. Finally, real‐world applications of the work have been found in robotics. The controller has been implemented on the robotic manipulator and the dynamic model of aerial robotic vehicles to prove its effectiveness and efficiency.
Adaptive optimal tracking control with novel event‐triggered formulation for a type of nonlinear systems
Authors: Wang Ding , Hu Lingzhi , Qiao Junfei
Published: September 2022

In this article, an event‐based intelligent critic algorithm is developed to address the optimal tracking control problem for a type of discrete‐time nonlinear systems. The nonlinear optimal tracking control design is replaced by solving the optimal regulation problem of the error system. Then, the generalized value iteration algorithm is employed to obtain the admissible tracking control law with off‐line learning. Next, a novel triggering condition is designed to reduce the update times of the controller and improve the resource utilization. It is emphasized that this triggering condition is established based on the iteration of the time‐triggered mechanism. Moreover, in order to realize the cost guarantee of the error system, the real cost function is proved to possess a predetermined upper bound. By analysis, it is shown that the error system is asymptotically stable while the tracking error and the sampling signal are uniformly ultimately bounded during the process of training neural networks. Finally, two examples are conducted to demonstrate the effectiveness of the proposed algorithm.
Microtissue‐Based Bioink as a Chondrocyte Microshelter for DLP Bioprinting
Authors: Xie Xinfang , Wu Shuang , Mou Shan , Guo Nengqiang , Wang Zhenxing , Sun Jiaming
Published: September 2022

Bioprinting specific tissues with robust viability is a great challenge, requiring a delicate balance between a densely cellular distribution and hydrogel network crosslinking density. Microtissues composed of tissue‐specific mesenchymal stem cells and extra cellular matrix (ECM) particles provide an alternative scheme for realizing biomimetic cell density and microenvironment. Nevertheless, due to their instability during manufacturing, scarce efforts have been made to date to assemble them using rapid prototyping methods. Here, a novel microtissue bioink with good printability and cellular viability maintenance for digital light processing (DLP) bioprinting is introduced. Generally, the microtissue bioink is prepared by crosslinking acellular matrix microparticles and GelMA hydrogel with a specific proportion. The microtissue bioink exhibits the desired mechanical properties, swelling ratio, and has almost no influences on printability. For instance, a DLP bioprinted ear with a precise auricle structure using microtia chondrocytes microtissue boink is created. Additionally, the chondrocytes in the printed ears show obvious advantages in cell proliferation in vitro and auricular cartilage regeneration in vivo. The microtissue composite bioink for DLP printing not only enables accurate assembly of organ building blocks but also provides a 3D shelter to ensure printed cells' viability.
Weakening the Solvating Power of Solvents to Encapsulate Lithium Polysulfides Enables Long‐Cycling Lithium–Sulfur Batteries
Authors: Hou Li‐Peng , Li Zheng , Yao Nan , Bi Chen‐Xi , Li Bo‐Quan , Chen Xiang , Zhang Xue‐Qiang , Zhang Qiang
Published: September 2022

Long cycling lifespan is a prerequisite for practical lithium–sulfur batteries yet is restricted by side reactions between soluble polysulfides and the lithium‐metal anode. The regulation on solvation structure of polysulfides renders encapsulating polysulfides electrolytes (EPSE) as a promising solution to suppress the parasitic reactions. The solvating power of the solvents in the outer solvent shell of lithium polysulfides is critical for the encapsulation effect of EPSE. Herein, 1,1,2,2‐tetrafluoroethyl‐2,2,3,3‐tetrafluoropropyl ether (HFE) is demonstrated as a superior outer‐shell solvent to construct EPSE. Based on the large steric hindrance of the fluorohydrocarbon chains, the electron‐withdrawing perfluoro segment (CF2 further endows HFE with prominently weak solvating power. The HFE‐EPSE improves the lifespan from 54 to 135 cycles for lithium–sulfur batteries with an ultrathin lithium‐metal anode (50 µm) and high‐areal‐loading sulfur cathode (4.4 mg cm−2). Furthermore, a 334 Wh kg−1 lithium–sulfur pouch cell (2.4 Ah level) with HFE‐EPSE stably undergoes 25 cycles. This work demonstrates the role of weakening solvating power of outer‐shell solvents to construct superior EPSE and inspires the significance of the solvation chemistry of polysulfides to achieve practical lithium–sulfur batteries.
Engineering 3d–2p–4f Gradient Orbital Coupling to Enhance Electrocatalytic Oxygen Reduction
Authors: Wang Xuan , Wang Jingwen , Wang Pu , Li Liangcheng , Zhang Xinyue , Sun Dongmei , Li Yafei , Tang Yawen , Wang Yu , Fu Gengtao
Published: September 2022

The development of highly efficient and economical materials for the oxygen reduction reaction (ORR) plays a key role in practical energy conversion technologies. However, the intrinsic scaling relations exert thermodynamic inhibition on realizing highly active ORR electrocatalysts. Herein, a novel and feasible gradient orbital coupling strategy for tuning the ORR performance through the construction of Co 3d‐O 2p‐Eu 4f unit sites on the Eu2O3–Co model is proposed. Through the gradient orbital coupling, the pristine ionic property between Eu and O atoms is assigned with increased covalency, which optimizes the eg occupancy of Co sites, and weakens the OO bond, thus ultimately breaking the scaling relation between *OOH and *OH at Co–O–Eu unit sites. The optimized model catalyst displays onset and half‐wave potential of 1.007 and 0.887 V versus reversible hydrogen electrode, respectively, which are higher than those of commercial Pt/C and most Co‐based catalysts ever reported. In addition, the catalyst is found to possess superior selectivity and durability. It also reveals better cell performance than commercial noble‐metal catalysts in Zn–air batteries in terms of high power/energy densities and long cycle life. This study provides a new perspective for electronic modulation strategy by the construction of gradient 3d–2p–4f orbital coupling.
Highly Efficient and Robust Full‐Color Organic Afterglow through 2D Superlattices Embedment
Authors: Zhang Jingyu , Xu Shen , Zhang Longyan , Wang Xin , Bian Yanfang , Tang Senlin , Zhang Runqi , Tao Ye , Huang Wei , Chen Runfeng
Published: September 2022

Purely organic afterglow (POA) originating from the slow radiative decay of stabilized triplet excited states has shown amazing potential in many fields. However, achieving highly stable POA with high phosphorescent quantum yield (PhQY) and long lifetime is still a formidable challenge owing to the intrinsically active and sensitive nature of triplet excitons. Here, triplet excitons of phosphors are protected and stabilized by embedding in tricomponent trihapto self‐assembled 2D hydrogen‐bonded superlattices, which not only enables deep‐blue POA with high PhQY (up to 65%), ultralong lifetime (over 1300 ms) and the highest figure‐of‐merit at room temperature, but also achieves excellent stability capable of resisting quenching effects of oxygen, solvent, pressure, light, and heat. In addition, the POA color is tuned from deep‐blue to red via efficient Förster resonance energy transfer from the deep‐blue POA emitters to the fluorophores. Moreover, with the high‐performance, robust, and full‐color POA materials, flexible anti‐counterfeit displays and direct‐current (DC)‐driven lifetime‐encrypted color Morse Code applications are facilely realized.
Bioimaging with Upconversion Nanoparticles
Authors: Mettenbrink Evan M. , Yang Wen , Wilhelm Stefan
Published: September 2022

Bioimaging enables the spatiotemporal visualization of biological processes at various scales empowered by a range of different imaging modalities and contrast agents. Upconversion nanoparticles (UCNPs) represent a distinct type of such contrast agents with the potential to transform bioimaging due to their unique optical properties and functional design flexibilities. This review explores and discusses the opportunities, challenges, and limitations that UCNPs exhibit as bioimaging probes and highlights applications with spatial dimensions ranging from the single nanoparticle level to cellular, tissue, and whole animal imaging. Recent advancements in bioimaging applications enabled by UCNPs, including super‐resolution techniques and multimodal imaging methods are summarized, and a perspective on the future potential of UCNP‐based technologies in bioimaging research and clinical translation is provided. This review may provide a valuable resource for researchers interested in exploring and applying UCNP‐based bioimaging technologies.
A Biomimetic Nanomedicine Targets Orthotopic Glioblastoma by Combinatorial Co‐Delivery of Temozolomide and a Methylguanine‐DNA Methyltransferase Inhibitor
Authors: Wang Yibin , Sun Yajing , Geng Nan , Zheng Meng , Zou Yan , Shi Bingyang
Published: September 2022

Glioblastoma (GBM) is the most aggressive intracranial tumor that occurs in the central nervous system (CNS) and has no effective treatment due to the fact of drug resistance. To combat drug resistance, TMZ is generally administrated in combination with other chemotherapeutic drugs. Unfortunately, drug combinations used to date only show modest improvements in anti‐tumor effects and have increased toxicity. Herein, an ApoE peptide decorated GBM cancer cell membrane camouflaged nanomedicine (AMNPs@TMZ+LM) to specifically co‐deliver TMZ and the MGMT inhibitor lomeguatrib (LM) for combinatorial GBM treatment is developed. Incorporation of LM not only effectively suppresses the repair of damaged DNA, but also inhibits tumor cell proliferation by inducing cell cycle arrest. Importantly, this biomimetic nanomedicine achieves high BBB penetration and enhances sensitivity to both TMZ‐resistant (U251‐TR) and GBM stem cells (GSCs). Notably, AMNPs@TMZ+LM results in significant inhibition of the growth of orthotopically implanted U251‐TR tumor in mice. In comparison, treatment with single drug loaded nanomedicines results in compromised anti‐GBM effects. Histological analyses and blood parameter studies show good biocompatibility of the nanomedicine. Hence, this biomimetic nanomedicine provides a potential new approach to overcome the limitations of current GBM chemotherapy regimens by co‐delivery of TMZ and the MGMT inhibitor LM.
Multiplicity of sustainability standards and potential trade costs in the palm oil industry
Authors: Hidalgo Laura M. G. , de Faria Rosane N. , Souza Piao Roberta , Wieck Christine
Published: September 2022

The growing impact of the global production of agricultural commodities has created new regulations that aim at a more sustainable trade. Sustainability standards (SS) are essential tools for transnational trade governance because they increase the possibility of recognizing products from sustainable sources. However, there is currently a proliferation of SS in almost every industry. This paper proposes a conceptual framework to establish how standard interactions such as competition, cooperation, and overlap shape the impact of multiplicity on trade costs. We apply the framework to the palm oil industry by using the information on three aspects of SS schemes: the requirements, the institutional design, and the cooperation strategies. Our results indicate that the North–South multiplicity in the palm oil market is characterized by high overlap, but there exists a balanced co‐opetition in the standard market. As the cooperation strategies between the SS schemes are very shallow, there might be potential trade costs associated with the SS multiplicity in the palm oil industry. [EconLit Citations: Q01 Sustainable Development, Q17 Agriculture in International Trade, Q18 Agricultural PolicyFood Policy].
Use of Superhydrophobic Surfaces for Performance Enhancement of Aerial–Aquatic Vehicles
Authors: Gortat Daniel , Ancel Alejandro Ortega , Farinha Andre , Zufferey Raphael , Kovac Mirko
Published: September 2022

Aerial–aquatic robotic vehicles show great potential in assisting in disaster response and environmental monitoring. However, to undertake these missions, they need to overcome the challenges of power requirements for takeoff and the difficulty of transitioning reliably between the air and water media. The use of superhydrophobic surfaces offers solutions to these challenges by reducing the wetted surface area of such robotic vehicles. In this article, a range of superhydrophobic surfaces is analyzed for wettability and robustness performance to ascertain their benefits as a design feature for drag reduction in aerial–aquatic robotic vehicles. The silicon dioxide nanoparticle spray coating show the most superhydrophobicity measuring a static water contact angle of 174.8°. The coating's robustness tests yield a similar performance to that of laser‐engraved brass with 200 μm groove separation, displaying a contact angle of 133.0° after ten finger strokes. The silicon dioxide nanoparticle spray is then used for drag reduction testing due to its ease of coating complex 3D geometries among the techniques explored in this study. The spray is applied to the hull of a sailing–flying robot, which resulted in the robot's drag reduction averaging 40% in the hydroplaning regime.
An Anthropomorphic Musculoskeletal System with Soft Joint and Multifilament Pneumatic Artificial Muscles
Authors: Lin Zhonghan , Shao Qi , Liu Xin-Jun , Zhao Huichan
Published: September 2022

Robotic manipulators are expected to enhance humans’ ability to grasp and manipulate objects. Soft materials offer innovative opportunities to develop robotic manipulators that are inherently compliant, physically robust, and interact safely with humans. Herein, a soft‐material‐based musculoskeletal module is reported. Inspired by the human shoulder complex, a lightweight and compact three‐degree‐of‐freedom (three‐DOF) membrane‐covered passive joint with a large range of motion (>180°) in all DOFs, small rotational resistance (<0.2 Nm), and large axial load‐bearing capacity (>80 N) benefiting from the hydrostatic stress of its filled liquid is developed. To actuate the joint, a helical‐structured pneumatic artificial muscle fiber (HPAMF) with a high energy density of 36 J kg−1is designed. Moreover, it is investigated how to eliminate the Mullins effect of fibers made from silicone rubber to increase the repeatability and consistency between fibers and ensure the musculoskeletal system achieves stable motion by overcoming the snap‐through instability. Finally, the musculoskeletal system achieves open‐loop controlled three‐DOF motion with load‐bearing capacity in a compact space via pre‐stretching and antagonistic arrangement of 60 HPAMFs as 12 independent bundles. It is believed that the proposed musculoskeletal module can be assembled and developed as a soft manipulator to assist people in their activities of daily living.
Rotation Control, Interlocking, and Self‐Positioning of Active Cogwheels
Authors: Martinet Quentin , Aubret Antoine , Palacci Jeremie
Published: September 2022

Gears and cogwheels are elemental components of machines. They restrain degrees of freedom and channel power into a specified motion. Building and powering small‐scale cogwheels are key steps toward feasible micro and nanomachinery. Assembly, energy injection, and control are, however, a challenge at the microscale. In contrast with passive gears, whose function is to transmit torques from one to another, interlocking and untethered active gears have the potential to unveil dynamics and functions untapped by externally driven mechanisms. Here, it is shown the assembly and control of a family of self‐spinning cogwheels with varying teeth numbers and study the interlocking of multiple cogwheels. The teeth are formed by colloidal microswimmers that power the structure. The cogwheels are autonomous and active, showing persistent rotation. Leveraging the angular momentum of optical vortices, we control the direction of rotation of the cogwheels. The pairs of interlocking and active cogwheels that roll over each other in a random walk and have curvature‐dependent mobility are studied. This behavior is leveraged to self‐position parts and program microbots, demonstrating the ability to pick up, direct, and release a load. The work constitutes a step toward autonomous machinery with external control as well as (re)programmable microbots and matter.
Why a clinical trial is as good as its outcome measure: A framework for the selection and use of cognitive outcome measures for clinical trials of Alzheimer's disease
Authors: Jutten Roos J. , Papp Kathryn V. , Hendrix Suzanne , Ellison Noel , Langbaum Jessica B. , Donohue Michael C. , Hassenstab Jason , Maruff Paul , Rentz Dorene M. , Harrison John , Cummings Jeffrey , Scheltens Philip , Sikkes Sietske A. M.
Published: September 2022

A crucial aspect of any clinical trial is using the right outcome measure to assess treatment efficacy. Compared to the rapidly evolved understanding and measurement of pathophysiology in preclinical and early symptomatic stages of Alzheimer's disease (AD), relatively less progress has been made in the evolution of clinical outcome assessments (COAs) for those stages. The current paper aims to provide a benchmark for the design and evaluation of COAs for use in early AD trials. We discuss lessons learned on capturing cognitive changes in predementia stages of AD, including challenges when validating novel COAs for those early stages and necessary evidence for their implementation in clinical trials. Moving forward, we propose a multi‐step framework to advance the use of more effective COAs to assess clinically meaningful changes in early AD, which will hopefully contribute to the much‐needed consensus around more appropriate outcome measures to assess clinical efficacy of putative treatments.

Highlights

We discuss lessons learned on capturing cognitive changes in predementia stages of AD.

We propose a framework for the design and evaluation of performance based cognitive tests for use in early AD trials.

We provide recommendations to facilitate the implementation of more effective cognitive outcome measures in AD trials.
A Characterization of Entangled Two‐Qubit States via Partial‐Transpose‐Moments
Authors: Zhang Lin , Zhao Ming‐Jing , Chen Lin , Xiang Hua , Shen Yi
Published: September 2022

Although quantum entanglement is an important resource, its characterization is quite challenging. The partial transposition is a common method to detect bipartite entanglement. In this paper, the authors study the partial‐transpose(PT)‐moments of two‐qubit states, and completely describe the whole region, composed of the second and third PT‐moments, for all two‐qubit states. Furthermore, they determine the accurate region corresponding to all entangled two‐qubit states. The states corresponding to those boundary points of the whole region, and to the border lines between separable and entangled states are analyzed. As an application, they characterize the entangled region of PT‐moments for the two families of Werner states and Bell‐diagonal states. The relations between entanglement and the pairs of PT‐moments are revealed from these typical examples. They also numerically plot the whole region of possible PT‐moments for all two‐qubit X‐states, and find that this region is almost the same as the whole region of PT‐moments for all two‐qubit states. Moreover, they extend their results to detect the entanglement of multiqubit states. By utilizing the PT‐moment‐based method to characterize the entanglement of the multiqubit states mixed by the GHZ and W states, they propose an operational way of verifying the genuine entanglement in such states.
The Microscopic Origin of Second Harmonic Generation Response: The Spatial Structure of Instantaneous Dipole Moments in Electron Excitation
Authors: Li ZhenHua , Zhang Anmin , Luo Hong‐Gang
Published: September 2022

A deep understanding on the crucial factors of the enhanced macroscopic second harmonic generation (SHG) in some deep‐ultraviolet nonlinear optical (NLO) materials is needed to design new NLO materials. Since an optical process relates to the electron excitation and polarization simultaneously, the instantaneous dipole moments and their structures in excitation should be seriously taken account to seek the principal factor in SHG response. In this work, we study the Ba4B11O20F (BBOF), a NLO material, by using the orbital projection technique. From the projected SHG of our theoretic calculation, we recognize the principal dipole moment of the dominant influence on SHG and the relevant atom groups between which the dipole moment is accommodated. With the conclusion that the dipole moment with the most significant influence on SHG is the one between the oxygen–boron polyhedral anion group and barium cation, we predict that Ba4Al11O20F (BAOF) has a comparable SHG response.
Influence of alternating magnetic field's frequency and exposure time on distribution of α‐Fe2O3/TiO2 fillers for gas separation membranes: Quantitative approach
Authors: Yap Yun Kee , Oh Pei Ching , Chew Thiam Leng , Asif Jamil
Published: September 2022

Poly(2,6‐dimethyl‐1,4‐phenylene oxide) membrane with magnetic α‐Fe2O3/TiO2 fillers was exposed to varying alternating magnetic field (AMF) duration and frequency. The AMF threshold time was 8 min as mixed‐matrix membrane (MMM) exposed to 11 min experienced an abrupt increase in permeability of CO2 by 785% and CH4 by 1322%. Although quantitative measurements showed relatively excellent values at 11 min, prolonged exposure time reduces selectivity, possibly due to interruption in the polymer‐filler interfacial area densification process. Filler distribution measured quantitatively via optical microscope and MATLAB also revealed that MMM exposed to 3.3 kHz presents the greatest dispersion metric with the least agglomeration. MMM exposed to the frequency of 30 Hz or 330 kHz suffered from either increased agglomeration size or worse dispersion. Consequently, their gas separation performances were lower than MMM exposed to 3.3 kHz. Above a critical frequency, repulsive hydrodynamic forces overcome the attractive forces between magnetic fillers.
A dielectrophoresis proof of concept of polystyrene particles and in‐vitro human epidermal keratinocytes migration for wound rejuvenation
Authors: Deivasigamani Revathy , Maidin Nur Nasyifa Mohd , Nasir Nur Shahira Abdul , Low Mei Xian , Kayani Aminuddin Bin Ahmad , Mohamed Mohd Ambri , Buyong Muhamad Ramdzan
Published: September 2022

Diabetes affects approximately 170 million people worldwide, is expected to double by 2030, and is a severe problem. Electrical stimulation (ES) via dielectrophoresis (DEP) technique may be an effective alternative in enhancing healing rates in diabetic patients with open ulcers. This research used DEP force (FDEP) to manipulate 3.2, 4.8, 10, and 15 μm polystyrene (PS) particles to predict the migration capability of human epidermal keratinocytes (HEKs). A numerical modeling method, MyDEP, was used to predict the interpretation of Clausius–Mossotti factors of PS particles and HEKs. The finite element method computes the electric field intensity and particle trajectory based on DEP and drag forces in their respective medium. DEP experiments on numerous size PS particles and alive HEKs were carried out in a tapered aluminium microelectrode array using a non‐uniform electric field. The distinct PS particles exhibit positive DEP (PDEP), crossover frequency (fXO), and negative DEP (NDEP), whereas the HEKs experience, only NDEP due to its high conductive medium in frequency ranges from 100 kHz to 1 MHz. Finally, the DIPP‐MotionV analysis shows that particle mobility between speed and acceleration is statistically considerable. When an appropriate frequency is applied to HEKs in random locations, the FDEP aligns at the desired target position based on its dielectric properties, which accelerates wound healing in in‐vivo conditions.
Synthesis of statistical poly(ethylene terephthalate‐co‐2,6‐naphthalate) (co)polymers and study on their properties: Thermal and barrier properties
Authors: Quan Lijun , Liu Zhenguo , Zhang Qiuyu , Li Zhongming , Chen Yanhui
Published: September 2022

In this paper, a series of poly(ethylene terephthalate‐co‐2,6‐naphthalate) (PETN) (co)polyesters with different naphthalene ring contents were synthesized via a two‐step transesterification and polycondensation. The effects of the monomer compositions on the sequence distribution, crystallization, mechanical, thermal, and barrier properties of the (co)polymers were investigated systematically. The results showed that the introduction of naphthalene ring units (NDC) changed the sequence length of the PETN and disrupted the orderly arrangement of the PETN molecular chains, thus affecting the aggregated structure and properties of the copolymer. When the NDC content was less than 30%, the PETN copolymers displayed good ductility and higher yield strength comparable to PET, and the heat distortion temperature (HDT), thermal stability properties, and barrier properties of the copolymer were also improved. In addition, the diffusion kinetics of water and oxygen molecules in the (co)polymer were investigated by the MS program simulation software. The differences in gas barrier properties of the different PETN (co)polymers were explained at the molecular level. This study provides a systematic theoretical basis and comprehensive practical guidance for the preparation of high‐performance copolyester materials.
Human‐in‐the‐loop development of spatially adaptive ground point filtering pipelines—An archaeological case study
Authors: Doneus Michael , Höfle Bernhard , Kempf Dominic , Daskalakis Gwydion , Shinoto Maria
Published: September 2022

LiDAR data have become indispensable for research in archaeology and a variety of other topographic applications. To derive products (e.g. digital terrain or feature models, individual trees, buildings), the 3D LiDAR points representing the desired objects of interest within the acquired and georeferenced point cloud need to be identified. This process is known as classification, where each individual point is assigned to an object class. In archaeological prospection, classification focuses on identifying the object class ‘ground points’. These are used to interpolate digital terrain models exposing the microtopography of a terrain to be able to identify and map archaeological and palaeoenvironmental features. Setting up such classification workflows can be time‐consuming and prone to information loss, especially in geographically heterogeneous landscapes. In such landscapes, one classification setting can lead to qualitatively very different results, depending on varying terrain parameters such as steepness or vegetation density. In this paper, we are focussing on a special workflow for optimal classification results in these heterogeneous environments, which integrates expert knowledge. We present a novel Python‐based open‐source software solution, which helps to optimize this process and creates a single digital terrain model by an adaptive classification based on spatial segments. The advantage of this approach for archaeology is to produce coherent digital terrain models even in geomorphologically heterogenous areas or areas with patchy vegetation. The software is also useful to study the effects of different algorithm and parameter combinations on digital terrain modelling with a focus on a practical and time‐saving implementation. As the developed pipelines and all meta‐information are made available with the resulting data set, classification is white boxed and consequently scientifically comprehensible and repeatable. Together with the software's ability to simplify classification workflows significantly, it will be of interest for many applications also beyond the examples shown from archaeology.
Determination and analysis of sex ratios in heme oxygenase 1 gene targeted mouse embryos
Authors: Jain Sidhant , Nandi Gouri , Choubey Pooja , Rana Meenakshi , Basu‐Modak Sharmila
Published: September 2022

Heme oxygenase 1 or Hmox1 enzyme is involved in catalyzing the first and rate‐limiting step in heme breakdown reactions. Many studies have reported a partial lethality of Hmox1 knockout mice obtained from heterozygous breeding pairs. Similar results were obtained in our transgenic mice colony and a sex specific bias was observed in the favor of males in the adult mice. Hmox1 independent factors which could have caused this bias were initially analyzed and it was found that those factors were not a reason behind this anomaly. Certain studies involving gene knockout hinted toward a prenatal or neonatal lethality of female knockout mice embryos or pups, respectively. In order to check if this bias was occurring in embryonic stages, that is, either if mutant female embryos were dying or if heterozygous mothers were not carrying embryos to term, we analyzed the sex‐ratios in mid‐ and late‐gestational ages (9.5–13.5 dpc and 14.5–18.5 dpc, respectively). Our results did not indicate any significant difference in the sex ratios in embryonic stages; hence, it was concluded that females are not dying in embryonic stages. It can be speculated that these deaths were probably occurring at neonatal age. More studies are required to confirm that the lack of Hmox1 gene products is the sole reason for this female lethality.
Glückliche Fügung: Experiments’ Potential to Integrate Disciplines**
Authors: Schürch Caterina
Published: September 2022

This essay reviews the discipline‐connecting potential of experimentation. Two examples are used to illustrate how researchers in the first half of the twentieth century profitably combined resources from different disciplines in their experiments. These experiments were designed to test mechanism models describing chemical processes underlying the behavior of biological systems. The researchers had clear expectations about how certain interventions should affect the behavior of the organisms studied, if that behavior was indeed based on the presumed chemical processes. They manipulated the organisms in the relevant ways and determined how the behavior of the organisms changed as a result.
Experimental Systems in the Co‐Construction of Scientific Knowledge**
Authors: Morange Michel
Published: September 2022

The publication of Toward a History of Epistemic Things 25 years ago was a landmark in science studies. Not only was the book a brilliant overview of new research trends, but it was also a personal and highly original contribution because of its emphasis on the major role of experimental systems in the construction of scientific knowledge. The paths that it opened have not yet been fully explored. More seriously, the ambition of the author to reinforce the value of scientific knowledge by the role of experimental systems in its construction has not been pursued.
An Epistemology of Scientific Practice: Positioning Hans‐Jörg Rheinberger in Twentieth‐Century History and Philosophy of Biology**
Authors: Méthot Pierre‐Olivier
Published: September 2022

In this article, I first outline the professionalization of the history and philosophy of biology from the 1960s onward. Then, I attempt to situate the work of Hans‐Jörg Rheinberger with respect to this field. On the one hand, Rheinberger was marginal with respect to Anglo‐American philosophical tradition; on the other, he was very influential in building up an integrated history and philosophy of the life sciences community at the Max Planck Institute for the History of Science in Berlin and beyond. This marginality results, I suggest, from three main sources: his use of concepts coming from continental traditions in the study of the life sciences, which are foreign to Anglo‐American philosophers of science; his focus on practices instead of theories; and his research trajectory as a molecular biologist, which led him to be critical of disciplinary boundaries. As a first step in situating and historicizing Rheinberger's trajectory, this article invites comparative studies and calls for a history of “continental philosophy of biology” in the twentieth century.
From Organismic Biology as History and Philosophy to the History and Philosophy of Biology—the Work of Hans‐Jörg Rheinberger in the German Context**
Authors: Reiß Christian
Published: September 2022

In this paper, I ask about the broader context of the history and philosophy of biology in the German‐speaking world as the place in which Hans‐Jörg Rheinberger began his work. Three German philosophical traditions—neo‐Kantianism, phenomenology, and Lebensphilosophie—were interested in the developments and conceptual challenges of the life sciences in the late nineteenth and early twentieth centuries. Their reflections were taken up by life scientists under the terms theoretische Biologie (theoretical biology) and allgemeine Biologie (general biology), i. e., for theoretical and methodological reflections. They used historical and philosophical perspectives to develop vitalistic, organicist, or holistic approaches to life. In my paper, I argue that the resulting discourse did not come to an end in 1945. Increasingly detached from biological research, it formed an important context for the formation of the field of history and philosophy of biology. In Rheinberger's work, we can see the “Spalten” and “Fugen”—the continuities and discontinuities—that this tradition left there.
“How Many Individuals Consider Themselves to Be Cell Biologists but Are Informed by the Journal That Their Work Is Not Cell Biology”**
Authors: Worliczek Hanna Lucia
Published: September 2022

What can we gain from co‐analyzing experimental cultures, regionalization, and disciplinary phenomena of late twentieth century life sciences under our historiographic looking glass? This essay investigates the potential of such a strategy for the case of cell biology after 1960. By merging perspectives from historical epistemology inspired by the work of Hans‐Jörg Rheinberger with a focus on boundary work in the realm of scientific publishing, community building, and disciplinary norms, a set of understudied scientific practices is exposed. These practices, historically subsumed under the label descriptive, have been as central in cell biology as hypothesis‐driven research aiming at mechanistic explanations of cellular function. Against the background of an increasing molecular‐mechanistic imperative in cell biology since the late 1960s, knowledge from descriptive practices was often judged as having low value but was nonetheless frequently cited and considered essential. Investigating the underlying epistemic practices and their interactions with disciplinary gatekeeping phenomena (as policed by journals and learned societies) provides historiographic access to the plurality of experimental cultures of cell biology, scattered into many interdisciplinary research fields—with some of them only partially engaged with mechanistic questions.
Approaches in Post‐Experimental Science. The Case of Precision Medicine**
Authors: Meunier Robert
Published: September 2022

In the introduction to hisSpalt und Fuge, Hans‐Jörg Rheinberger points to the possibility that we are currently experiencing a new turning point regarding forms of experimentation, which is characterized by the growing importance of high‐throughput methods and big data analytics. This essay will explore the thesis that data‐intensive research indeed constitutes a form of post‐experimental research by interrogating research practices in precision medicine. Section 1 will introduce this thesis and highlight salient features of precision medicine as an example of post‐experimental research. Section 2 suggestsapproachas a category that is broader thanexperimental system, as discussed by Rheinberger, and can serve to analyze and compare diverse forms of research, including experimental and post‐experimental practices. The essay concludes with a reflection on how categories developed for the historiography of recent science might require an update when the science or its context changes (section 3).
“You've Got to Work on This Axon”: J. Z. Young and Squid Giant Axon Preparations in 20th‐Century Neurobiology**
Authors: Maxson Jones Kathryn
Published: September 2022

Employing and extending Hans‐Jörg Rheinberger's analytical concept of epistemic things, this essay proposes one reason why squid giant axons, unusually large invertebrate nerve fibers, had such great impacts on twentieth‐century neurobiology. The 1930s characterizations of these axons by John Zachary Young reshaped prevailing assumptions about nerve cells as epistemic things, I argue. Specifically, Young's preparations of these axons, which consisted of fibers attached to laboratory technologies, highlighted similarities between giant axons and more familiar ones via lines of comparative study common to aquatic biology. Young's work convinced other biologists that the squid giant fibers were, in fact, axons, despite their unusual fused (syncytial) structures, thereby promoting further studies, such as intracellular measurements, made possible by the fiber's size. Tracing direct relations between preparations of squid axons and broader interpretations of neurons as epistemic things, this paper renders an actors’ category, “preparations,” into an analytical one. In turn, it offers glimpses into how aquatic organisms shaped twentieth‐century neurobiology and how local experiments can drive broader, disciplinary changes.
Narratives of Genetic Selfhood**
Authors: Creager Angela N. H.
Published: September 2022

This essay considers the mid‐twentieth century adoption of genetic explanations for three biological phenomena: nutritional adaptation, antibiotic resistance, and antibody production. This occurred at the same time as the hardening of the neo‐Darwinian Synthesis in evolutionary theory. I argue that these concurrent changes reflect an ascendant narrative of genetic selfhood, which prioritized random hereditary variation and selection through competition, and marginalized physiological or environmental adaptation. This narrative was further reinforced by the Central Dogma of molecular biology and fit well with liberal political thought, with its focus on the autonomous individual. However, bringing biological findings into line with this narrative required modifying the notion of the gene to account for various kinds of non‐Mendelian inheritance. Hans‐Jörg Rheinberger's reflections on narrative and experiment are valuable in thinking about the friction between the postwar ideal of genetic selfhood and actual observations of how organisms adapt in response to the environment.
Precision Medicine: Historiography of Life Sciences and the Geneticization of the Clinics**
Authors: Löwy Ilana
Published: September 2022

In 2013, Hans Jörg Rheinberger proposed that Mendelian genetics and molecular biology were “scientific ideologies,” that is, for him they are systems of thought whose objects are hyperbolic; they are not, or not yet, in the realm of and not, or not yet, under the control of that system. This article proposes that precision medicine today is a scientific ideology and analyses the implications of this statement for historians of biology, genetics, and medicine.
The Electrophoretic Revolution in the 1960s: Historical Epistemology Meets the Global History of Science and Technology**
Authors: Suárez‐Díaz Edna
Published: September 2022

This paper useszone electrophoresis, one of the most frequently used tools in molecular biology, to explore two ideas derived from Hans‐Jörg Rheinberger's reflections on experiments. First, the constraining role played by technical objects—instrumentation and material conditions—in the production of knowledge or epistemic things. Second, the production of interconnected experimental systems by such technical objects, which results in the unexpected entanglement of research fields and experimental cultures. By the beginning of the 1960s, the inception of zone electrophoresis in laboratories around the world transformed—some say, revolutionized—the study of proteins. Even today, electrophoresis continues to open research venues and questions in biomedicine, molecular biology, human genetics, and in the field of molecular evolution. In my essay, I seek to look at the interconnected lives of zone electrophoresis and address the broader social, and even global context, in which this apparently humble technique became a salient tool in the production of biological knowledge. In so doing, I aim to take the past and present of the history and historiography of experimental systems to the future, where experiments and technologies are interrogated as they are used in different geographies and contexts, including contexts of poverty.
Of Some Paradoxes in the Historiography of Molecular Biology**
Authors: de Chadarevian Soraya
Published: September 2022

Just when molecular biology is arguably delivering on some of its long‐promised medical applications—think mRNA vaccines, monoclonal antibody drugs, PCR testing, and gene therapies—the history of molecular biology has lost much of its shine. What not too long ago seemed like a burgeoning field of research with endless possibilities, is now often reduced to the “central dogma” that saw its apotheosis in the effort to sequence the human genome but has since unraveled. The essay will discuss several possible answers to this apparent paradox.
Tactile Vision, Epistemic Things and Data Visualization**
Authors: Borck Cornelius
Published: September 2022

Hans‐Jörg Rheinberger constructed his historical epistemology of epistemic things by analyzing experimental practices in molecular biology during the 1970s and 80s. With genetic sequencing and multi‐omics approaches, data has become a new resource in the life sciences, questioning the applicability of his concept of experimental system. By historicizing Rheinberger's epistemology, the paper focuses on its relatedness to Ludwik Fleck's notion of an aviso of resistance and points to a gradual shift in Rheinberger's emphasis, moving from an initial focus on writing and its differentiality to work on materials, preparations, and representations. By anchoring visualization in these material practices, Rheinberger also sheds new light on the changing conditions of experimentation in the life sciences due to big data, where visualization emphasizes patterns and correlations rather than substrates.
In the Circulation Sphere of the Biomolecular Age: Economics and Gender Matter**
Authors: von Schwerin Alexander
Published: September 2022

This contribution draws attention to the circulation of materialities and persons as a central feature in the constitution of experimental cultures. The protein and ribosome research at the Max Planck Society (MPG)—with a main focus on the research conducted by Brigitte Wittmann‐Liebold at the Max Planck Institute for Molecular Genetics—serves as an example to highlight some of the central conditions that determined the material circulation in molecular biology: the very organizational framework of gender and economics. In doing so, this contribution argues for a historical narrative that stresses the conditions facilitating the circulation of technologies, materials, and personnel. Histories of this kind contribute to an integrated view of the scientific, technological, social, political, economic, and cultural specificities of experimental cultures.
Hans‐Jörg Rheinberger as a Philosopher of Time**
Authors: Zimmermann Michael F.
Published: September 2022

When Hans‐Jörg Rheinberger proposed the concept ofepistemic things, he drew inspiration from the art historian George Kubler, who had considered the aesthetic object as resulting from problem‐solving processes inThe Shape of Time(1962). Kubler also demonstrated that a sequence of objects could retrace the progress that led to a solution that was afterwards accepted as the most classical. Parallel to Kubler, Rheinberger demonstrates how temporally extended activities of experimentation are condensed in the object, revealing the moments of innovation that lead to it. In the history of science as well as in art history, varioustrajectoriescan thus be grasped in the materially given. Rheinberger conceives of an object as a network of heterogeneoustime strings. However, these are manifold: they cannot be thought of as making up a homogeneous temporality encompassing all the others as a temporal container and synchronizing them within it. Since the discovery of the Anthropocene, we no longer separate natural from cultural time, and no hegemonic historical narrative can be taken as unifying all the others. Historical epistemology as proposed by Rheinberger will be read as a contribution to constructing new models of natural as well as of cultural time.
Evaluation of a tablet‐based assessment tool for measuring cognition among children 4–6 years of age in Ghana
Authors: Yuan Haiying , Ocansey Maku , Adu‐Afarwuah Seth , Sheridan Margaret , Hamoudi Amar , Okronipa Harriet , Kumordzie Sika M. , Oaks Brietta M. , Prado Elizabeth
Published: September 2022

Objectives

To investigate several basic psychometric properties, including construct, convergent and discriminant validity, of the tablet‐based Rapid Assessment of Cognitive and Emotional Regulation (RACER) among children aged 4–6 years in Ghana.

Methods

We investigated whether RACER tasks administered to children in Ghana could successfully reproduce expected patterns of performance previously found in high‐income countries on similar tasks assessing inhibitory control (e.g., slower responses on inhibition trials), declarative memory (e.g., higher accuracy on previously seen items), and procedural memory (e.g., faster responses on sequence blocks). Next, we assessed the validity of declarative memory and inhibitory control scores by examining associations of these scores with corresponding paper‐based test scores and increasing child age. Lastly, we examined whether RACER was more sensitive than paper‐based tests to environmental risk factors common in low‐ and middle‐income countries (LMICs).

Results

Of the 966 children enrolled, more than 96% completed the declarative memory and inhibitory control tasks; however, around 30% of children were excluded from data analysis on the procedural memory task due to missing more than half of trials. The performance of children in Ghana replicated previously documented patterns of performance. RACER inhibitory control accuracy score was significantly correlated with child age (r (929) = .09, p = .007). However, our findings did not support other hypotheses.

Conclusions

The high task completion rates and replication of expected patterns support that certain RACER sub‐tasks are feasible for measuring child cognitive development in LMIC settings. However, this study did not provide evidence to support that RACER is a valid tool to capture meaningful individual differences among children aged 4–6 years in Ghana.