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This study aims to provide a comprehensive review of the ethical, legal and social issues in human brain organoid research, with a view to different types of research and applications: in vitro research, transplantation into non-human animals, and biocomputing. Despite the academic and societal attention on the possibility that human brain organoids may be conscious, we have identified diverse issues in human brain organoid research and applications. To guide the complex terrain of human brain organoid research and applications, a multidisciplinary approach that integrates ethical, legal, and social perspectives is essential., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: JS is a Partner Investigator on an Australian Research Council grant (LP190100841) which involves industry partnership from Illumina. He does not personally receive any funds from Illumina. JS is a Bioethics Committee consultant for Bayer and a Bioethics Advisor for the Hevolution Foundation. Other authors declare no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier GmbH.. All rights reserved.)

Deep neural network (DNN) techniques, as an advanced machine learning framework, have allowed various image diagnoses in plants, which often achieve better prediction performance than human experts in each specific field. Notwithstanding, in plant biology, the application of DNNs is still mostly limited to rapid and effective phenotyping. The recent development of explainable CNN frameworks has allowed visualization of the features in the prediction by a convolutional neural network (CNN), which potentially contributes to the understanding of physiological mechanisms in objective phenotypes. In this study, we propose an integration of explainable CNN and transcriptomic approach to make a physiological interpretation of a fruit internal disorder in persimmon, rapid over-softening. We constructed CNN models to accurately predict the fate to be rapid softening in persimmon cv. Soshu, only with photo images. The explainable CNNs, such as Gradient-weighted Class Activation Mapping (Grad-Class Activation Mapping (CAM)) and guided Grad-CAM, visualized specific featured regions relevant to the prediction of rapid softening, which would correspond to the premonitory symptoms in a fruit. Transcriptomic analyses to compare the featured regions of the predicted rapid-softening and control fruits suggested that rapid softening is triggered by precocious ethylene signal-dependent cell wall modification, despite exhibiting no direct phenotypic changes. Further transcriptomic comparison between the featured and non-featured regions in the predicted rapid-softening fruit suggested that premonitory symptoms reflected hypoxia and the related stress signals finally to induce ethylene signals. These results would provide a good example for the collaboration of image analysis and omics approaches in plant physiology, which uncovered a novel aspect of fruit premonitory reactions in the rapid-softening fate., (© The Author(s) 2023. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists.)

In 2008, researchers created human three-dimensional neural tissue - known as the pioneering work of "brain organoids." In recent years, some researchers have transplanted human brain organoids into animal brains for applicational purposes. With these experiments have come many ethical concerns. It is thus an urgent task to clarify what is ethically permissible and impermissible in brain organoid research. This paper seeks (1) to sort out the ethical issues related to brain organoid research and application and (2) to propose future directions for additional ethical consideration and policy debates in the field. Toward (1), this paper first outlines the current state of brain organoid research, and then briefly responds to previously raised related ethical concerns. Looking next at anticipated scientific developments in brain organoid research, we will discuss (i) ethical issues related to in vitro brain organoids, (ii) ethical issues raised when brain organoids form complexes or have relationships with other entities, and (iii) ethical issues of research ethics and governance. Finally, in pursuit of (2), we propose research policies that are mindful of the ethics of brain organoid research and application and also suggest the need for an international framework for research and application of brain organoids.

There are many theories of the functions of consciousness. How these theories relate to each other, how we should assess them, and whether any integration of them is possible are all issues that remain unclear. To contribute to a solution, this paper offers a conceptual framework to clarify the theories of the functions of consciousness. This framework consists of three dimensions: (i) target, (ii) explanatory order, and (iii) necessity/sufficiency. The first dimension, target, clarifies each theory in terms of the kind of consciousness it targets. The second dimension, explanatory order, clarifies each theory in terms of how it conceives of the explanatory relation between consciousness and function. The third dimension, necessity/sufficiency, clarifies each theory in terms of the necessity/sufficiency relation posited between consciousness and function. We demonstrate the usefulness of this framework by applying it to some existing scientific and philosophical theories of the functions of consciousness., (© The Author(s) 2022. Published by Oxford University Press.)

Recent rapid progress in deep neural network techniques has allowed recognition and classification of various objects, often exceeding the performance of the human eye. In plant biology and crop sciences, some deep neural network frameworks have been applied mainly for effective and rapid phenotyping. In this study, beyond simple optimizations of phenotyping, we propose an application of deep neural networks to make an image-based internal disorder diagnosis that is hard even for experts, and to visualize the reasons behind each diagnosis to provide biological interpretations. Here, we exemplified classification of calyx-end cracking in persimmon fruit by using five convolutional neural network models with various layer structures and examined potential analytical options involved in the diagnostic qualities. With 3,173 visible RGB images from the fruit apex side, the neural networks successfully made the binary classification of each degree of disorder, with up to 90% accuracy. Furthermore, feature visualizations, such as Grad-CAM and LRP, visualize the regions of the image that contribute to the diagnosis. They suggest that specific patterns of color unevenness, such as in the fruit peripheral area, can be indexes of calyx-end cracking. These results not only provided novel insights into indexes of fruit internal disorders but also proposed the potential applicability of deep neural networks in plant biology., (© The Author(s) 2020. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

This article aims to present a map of consciousness studies, which consists of a list of fundamental questions about consciousness and existing approaches to them. The question list includes five fundamental categories: Definitional, Phenomenological, Epistemological, Ontological, and Axiological. Each fundamental category is divided into more determinate questions. Existing approaches to each question are also classified into a few groups, presenting principal researchers who take each kind of approach. In the final section, I demonstrate the usefulness of the proposed map of consciousness studies by applying it to examine the integrated information theory and the global workspace theory of consciousness., (Copyright © 2020 Niikawa.)

The subjective features of psychological phenomena have been studied intensively in experimental science in recent years. Although various methods have been proposed to identify subjective features of psychological phenomena, there are elusive subjective features such as the spatiotemporal structure of experience, which are difficult to capture without some additional methodological tools. We propose a new experimental method to address this challenge, which we call the contrast-based experimental phenomenological method (CEP). CEP proceeds in four steps: (i) front-loading phenomenology, (ii) online second-personal interview, (iii) questionnaire survey, and (iv) hypotheses testing. It differs from other experimental phenomenological methods in that it takes advantage of phenomenal contrasts in collecting phenomenological data. In this paper, we verify the validity and productivity of this method by applying it to binocular rivalry (BR). The study contributes to empirical research on BR in three respects. First, it provides additional evidence for existing propositions about the subjective features of BR: e.g. the proposition that the temporal dynamics of the experience depend upon subject-dependent parameters such as attentional change. Second, it deepens our understanding of the spatiotemporal structures of the transition phase of BR. Third, it elicits new research questions about depth experience and individual differences in BR. The presence of such contributions demonstrates the validity and productivity of CEP., (© The Author(s) 2020. Published by Oxford University Press.)

The objective of this study was to elucidate the dynamic mechanism of infant tongue movement during sucking. We developed an integrated device with sensors for three-dimensional force measurements applied by the tongue to an artificial nipple. Three mini-size built-in cantilever sensors were installed in each of three sides of the regular hexagonal prism (nine sensors in total) inside the artificial nipple. Signals from the force sensors were amplified and displayed on a PC monitor via USB in real time. We conducted measurements using the system and confirmed that signals were outputted from all nine sensors. The output waveforms and force distributions showed that the force applied was larger at the nipple tip than at the nipple root and moved from the nipple root to the nipple tip.

In order to clarify the dynamic mechanisms involved in sucking by infants, we developed an artificial nipple with built-in force sensors and have measured the contact force between the tongue and the artificial nipple in infants including healthy, premature and low birth weight. In this study, we measured the force applied by the tongue on the artificial nipple in 10 healthy infants and in 10 infants who were also tube-fed and investigated the differences in dynamic actions between the two groups to extract factors involved in satisfactory sucking. The results showed that differences in the maximum force applied and in the time to reach the maximum force were found between infants with and without established oral feeding. For an infant to suck satisfactorily, 1) the time for the force to propagate from the tongue tip to the tongue root needs to constitute at least 8 % of the sucking period and 2) the force applied at the tongue tip needs to be at least 50% of the force at the tongue root.

Infants are known to suckle and ingest breast milk by wrapping the tongue around a nipple, writhing the tongue, and pressing the nipple. However, the dynamic mechanisms of tongue movement are still obscure, and factors related to sucking difficulties of infants are not well understood. We developed an artificial nipple installed with small cantilever-type sensors and directly measured the force applied on the nipple by the tongue. Small force sensors were arranged within the artificial nipple in a two-dimensional matrix of 3 × 2 to measure the force at 6 points. Subjects were 20 healthy infants (Group A) and 5 infants who had difficulty sucking (Group B). The latter could not breastfeed well and were fed from bottles or tubes. Informed consent was provided by the parents or guardians. The measured maximum force at the tip of the nipple was 1.4 ± 0.4 N and 1.2 ± 0.3 N (mean ± SD) in Groups A and B, respectively. At the base of the nipple, the maximum force recorded was 0.8 ± 0.5 N and 0.3 ± 0.3 N (mean ± SD), respectively, showing a statistically significant difference (p<0.05). The sucking period was 0.6 ± 0.1 s (mean ± SD) in both groups. The difference in time necessary to reach the maximum forces between the sensors at the tip and base was 39.7 ± 28.8 ms (mean ± SD) and 37.2 ± 75.9 ms in Groups A and B, respectively.

To establish an effective tool for the prevention of HIV-1 transmission, lectin-immobilized polystyrene nanospheres were synthesized and examined for their HIV-1 capture activity. When concanavalin A (Con A) was immobilized on the surface of polystyrene nanospheres (400 nm in diameter) with poly(methacrylic acid) branches and incubated with HIV-1 suspension at room temperature for 60 min, the nanospheres (Con A-NSs) achieved a >3.3 log and a 2.2 log reduction of viral infectivity in HIV-1 (IIIB strain) suspension at a concentration of 2 and 0.5 mg/ml, respectively. Meanwhile, Con A-free nanospheres, which were not immobilized with Con A, achieved only a 0.29 log reduction at 0.5 mg/ ml. Con A-NSs (2 mg/ml) could also reduce the gp120 level of III(B) and HE strains to <7.1% and 5.5% of each control, respectively. The combination of Con A-NS treatment followed by filtration with a microporous membrane efficiently removed virion-free gp120 as well as infectious viral particles from HIV-1 suspension. Electron microscopic examination demonstrated that HIV-1 virions were trapped on the surface of Con A-NSs. Thus, Con A-NSs can capture HIV-1 virions and gp120 with high affinity, and may have potential as an effective tool for the prevention of HIV-1 transmission.

A lectin such as concanavalin A (Con A) was immobilized on the surfaces of poly(methacrylic acid) branches covered with polystyrene nanospheres with a diameter of 360 nm, which were obtained by the free radical copolymerization of styrene with the poly(tert-butylmethacrylate) macromonomer, followed by hydrolysis. Using Con A-immobilized (0.3 microgram/cm2) nanospheres, the interaction of the nanospheres with HIV-1 was determined by the reduction of the gp120 level and the viral infectivity of the HIV-1 suspensions after a 60 min incubation at room temperatures. Con A-immobilized nanospheres achieved a 95 and a 77% reduction of the gp120 level and the infectivity at a concentration of 0.5 mg/mL, respectively, indicating the effective capture of the gp120 and the virions.