The whole prefrontal cortex is premotor cortex

We propose that the entirety of the prefrontal cortex (PFC) can be seen as fundamentally premotor in nature. By this, we mean that the PFC consists of an action abstraction hierarchy whose core function is the potentiation and depotentiation of possible action plans at different levels of granularity. We argue that the apex of the hierarchy should revolve around the process of goal-selection, which we posit is inherently a form of optimization over action abstraction. Anatomical and functional evidence supports the idea that this hierarchy originates on the orbital surface of the brain and extends dorsally to motor cortex. Accordingly, our viewpoint positions the orbitofrontal cortex in a key role in the optimization of goal-selection policies, and suggests that its other proposed roles are aspects of this more general function. Our proposed perspective will reframe outstanding questions, open up new areas of inquiry and align theories of prefrontal function with evolutionary principles. This article is part of the theme issue ‘Systems neuroscience through the lens of evolutionary theory’.

Optimization of Interactive Animation Capture System for Human Upper Limb Movement Based on XSENS Sensor

This paper uses the XSENS sensor inertial motion capture device to collect the experimental data of the human body’s typical motion and posture-upper limb movement, based on the angular acceleration kinematics parameters of the human body’s upper limbs and upper limbs. We study the characteristics of human kinematics, statics, and dynamics and construct the upper limb movement model of the human body. Secondly, based on the principle of human anatomy, the human body is divided into 23 segments, with 18 upper limbs and 36 degrees of freedom; some anatomical terms are defined, and a unified coordinate system for the upper limb model of the human body is planned and established. In the process of experimental simulation, on the basis of analyzing and summarizing the laws and characteristics of the upper limb angles of the hip upper limbs, knee upper limbs, and ankle upper limbs during walking, a general function of the upper limb angles of the three upper limbs changing with time during walking was established. On the basis of analyzing 40 sets of upper limb movement data, with the three parameters of height, weight, and upper limb movement cycle as independent variables, the general function coefficient solving equation is given through function fitting. Finally, the production of interactive animation of upper limb movement is taken as an example. Based on the acceleration sensor and three-axis gyroscope, the limbs during the movement of the upper limb motion data are collected, preprocessed, and transmitted, and then, coordinate correction and data filtering are used to output quaternary parameters to give Maya an animated character model. The animation interactive demonstration is carried out in the way of web 3D, and the XSENS sensor is explored in the animation capture.

Bypassing the Monster: A Faster and Simpler Optimal Algorithm for Contextual Bandits Under Realizability

We consider the general (stochastic) contextual bandit problem under the realizability assumption, that is, the expected reward, as a function of contexts and actions, belongs to a general function class [Formula: see text]. We design a fast and simple algorithm that achieves the statistically optimal regret with only [Formula: see text] calls to an offline regression oracle across all T rounds. The number of oracle calls can be further reduced to [Formula: see text] if T is known in advance. Our results provide the first universal and optimal reduction from contextual bandits to offline regression, solving an important open problem in the contextual bandit literature. A direct consequence of our results is that any advances in offline regression immediately translate to contextual bandits, statistically and computationally. This leads to faster algorithms and improved regret guarantees for broader classes of contextual bandit problems.

A pilot randomised prospective comparison of two approaches for tibial nailing using clinical and novel imaging outcome measures – study protocol

Fractures of the tibia are frequently treated with an intra-medullary nail. This can be inserted through either a supra-patella or infra-patella surgical incision. Concerns over potential damage to the cartilage of the knee with supra-patella insertion has impacted upon its adoption despite benefits in terms of easier nail placement and potentially reduced blood loss and pain. This randomised pilot study will use patient reported outcome measures (PROMS) and novel MRI sequences designed to assess damage to the structure of cartilage to compare these two methods of tibial intra-medullary nailing. Twenty individuals with tibial shaft fractures will be randomised to either method of nail insertion (ten individuals in each arm). MRI scans and PROMS will be used to assess cartilage damage and general function up to 6 months post operatively. The results of the study will be used to inform a potential multi-centre study.

Using productivity concept to predict material demand

Background: The issue of material demands prediction has been researched in industrial study and materials/ manufacturing technology many years ago. The previous researches based on stochastic model to discuss the quantities prediction of material demand. Some of them focus on multi-suppliers with characteristic function. Some use the information of past ordering quantities and ordering recency time. In these previous models, there is less study to discuss the impact of cost on material demand forecasting. Thus, this paper considers the productivities concept to make cost balance when forecasting material demand. The different probability distributions are demonstrated to portray the input (material demand) and output(cost). Methods: A case study with its empirical data is released to derive the probability function of cost and estimate the parameters of the proposed model. Results: The proposed model can extend to different distributions depending on different kind of cost or different type of industries and is more widely application. Conclusion: To consider manufacture's productivity, this model can help manager to control their cost and make a balance when ordering their materials. The model development of cost release a general function which makes it possible to extend different distributions depending on different kind of cost or different type of industries.

Unravelling Transmission in Epidemiological Models and its Role in the Disease-Diversity Relationship

With the decrease of biodiversity worldwide coinciding with an increase in disease outbreaks, investigating this link is more important then ever before. This review outlines the different modelling methods commonly used for pathogen transmission in animal host systems. There are a multitude of ways a pathogen can invade and spread through a host population. The assumptions of the transmission model used to capture disease propagation determines the outbreak potential, the net reproductive success (R0). This review offers an insight into the assumptions and motivation behind common transmission mechanisms and introduces a general framework with which contact rates, the most important parameter in disease dynamics, determines the transmission method. By using a general function introduced here and this general transmission model framework, we provide a guide for future disease ecologists for how to pick the contact function that best suites their system. Additionally, this manuscript attempts to bridge the gap between mathematical disease modelling and the controversially and heavily debated disease-diversity relationship, by expanding the summarized models to multiple hosts systems and explaining the role of host diversity in disease transmission. By outlining the mechanisms of transmission into a stepwise process, this review will serve as a guide to model pathogens in multi-host systems. We will further describe these models it in the greater context of host diversity and its effect on disease outbreaks, by introducing a novel method to include host species’ evolutionary history into the framework.

Microtubule disassembly by caspases is the rate-limiting step of cell extrusion

Epithelial cell death is essential for tissue homeostasis, robustness and morphogenesis. The expulsion of epithelial cells following caspase activation requires well-orchestrated remodeling steps leading to cell elimination without impairing tissue sealing. While numerous studies have provided insight about the process of cell extrusion, we still know very little about the relationship between caspase activation and the remodeling steps of cell extrusion. Moreover, most studies of cell extrusion focused on the regulation of actomyosin and steps leading to the formation of a supracellular contractile ring. However, the contribution of other cellular factors to cell extrusion has been poorly explored. Using the Drosophila pupal notum, a single layer epithelium where most extrusion events are caspase-dependent, we first showed that the initiation of cell extrusion and apical constriction are surprisingly not associated with the modulation of actomyosin concentration/dynamics. Instead, cell apical constriction is initiated by the disassembly of a medio-apical mesh of microtubules which is driven by effector caspases. We confirmed that local and rapid increase/decrease of microtubules is sufficient to respectively expand/constrict cell apical area. Importantly, the depletion of microtubules is sufficient to bypass the requirement of caspases for cell extrusion. This study shows that microtubules disassembly by caspases is a key rate-limiting steps of extrusion, and outlines a more general function of microtubules in epithelial cell shape stabilisation.

Variation in the intestinal microbiota of tadpole and adult Hynobius maoershanensis

The intestinal microbiota play an important role in the life of amphibians. The composition of the intestinal microbial community may vary by developmental stage. In this study, 16S rRNA high-throughput sequencing was used to study the intestinal microbiota of Hynobius maoershanensis tadpoles and adults that exclusively inhabit the Maoer Mountain swamp at an altitude of approximately 2000 m. The results indicated that there was no significant difference in intestinal microbiota between tadpoles and adults. Nevertheless, the abundance of intestinal microbiota in adults was much higher than that in tadpoles. Specifically, at the phylum level, Bacteroidetes was more abundant in adults than in tadpoles. At the genus level, Proteobacteria, Actinobacteria, Cyanobacteria, and Planctomycetes were more abundant in tadpoles, whereas Burkholderiaceae, Caedibacter, Bacteroides, and Serratia were more abundant in adults. A functional prediction analysis revealed that there was no significant difference between tadpoles and adults; however, the function of the intestinal microbiota in H. maoershanensis includes amino acid transport and metabolism, general function prediction only, transcription, energy production and conversion, liquid transport, and metabolism. The aquatic and terrestrial living environment of tadpoles and adults may be the main reason for the difference in intestinal microbiota between tadpoles and adults. Our study provides evidence of variations in the intestinal microbiota of tadpoles and adult amphibians, highlighting the influence of historical developments on the intestinal microbiota and the need for increased understanding of the importance of physiological characteristics in shaping intestinal microbiota of amphibians, which consequently help us to understand the adaptative mechanism of amphibians from an aquatic to a terrestrial environment.

Multi-component cognitive intervention for older adults with mixed cognitive levels: implementation and preliminary effectiveness in real-world settings

Background In most controlled studies of multi-component cognitive intervention, participants’ cognitive levels are homogenous, which is contrary to real-world settings. There is a lack of research studying the implementation of evidence-based cognitive intervention in communities. This study describes the implementation and preliminary effectiveness of a Multi-component Cognitive Intervention using Simulated Everyday Tasks (MCI-SET) for older adults with different cognitive levels in real-world settings. Methods Single group, pre-intervention assessment, post-intervention assessment, and 3-month follow-up research design. MCI-SET consists of 12 two-hour weekly sessions that include motor-cognitive tasks, cognitive training, and cognitive rehabilitation. One hundred and thirty participants, > = 65 and frail, dependence on > = one instrumental daily activity, or with confirmed dementia, from eight community centers were included. The primary outcome is general cognition (Montreal Cognitive Assessment-Taiwan, MoCA-T). Secondary outcomes are memory (Miami Prospective Memory Test, Digits Forward, Digits Backward), attention (Color Trail Test-Part 1), executive function (Color Trail Test-Part 2), and general function (Kihon Checklist-Taiwan). Results Pre-intervention workshop for group leaders, standardized activity protocols, on-site observation, and ten weekly conferences were conducted to ensure implementation fidelity. MCI-SET had an 85% retention rate and 96% attendance rate. The participants had a mean age of 78.26 ± 7.00 and a mean MoCA-T score of 12.55 ± 7.43. 73% were female. General cognition (Hedges’ g = 0.31), attention (Hedges’ g = 0.23), and general function (Hedges’ g = 0.31), showed significant post-intervention improvement with small effect size. Follow-ups showed maintained improvement in general cognition (Hedges’ g = 0.33), and delayed effect on attention (Hedges’ g = 0.20), short-term memory (Hedges’ g = 0.38), and executive function (Hedges’ g = 0.40). Regression analysis indicated that the intervention settings (day care centers vs neighborhood centers), the pre-intervention cognitive levels, and the pre-intervention general function of the participants were not associated with the outcomes. Conclusions MCI-SET is feasible and can improve the cognitive skills and general functions of older adults with heterogeneous cognitive skills or disabilities. It is essential to tailor programs to fit the interests of the participants and the culture of local communities. Group leaders must also have the skills to adjust the cognitive demands of the tasks to meet the heterogeneous cognitive levels of participants. Trial registration This study was retrospectively registered at clinicaltrials.gov (Identifier: NCT04615169).

A probe of cosmological models in modified teleparallel gravity

In this paper, we have investigated the physical behavior of cosmological models in modified Teleparallel gravity with a general function [Formula: see text] where [Formula: see text] and [Formula: see text] are model parameters and [Formula: see text] is the torsion scalar. We have considered a homogeneous and isotropic Friedman universe filled with perfect fluid. We have derived the deceleration parameter [Formula: see text] in terms of equation of state (EoS) parameter [Formula: see text] and Hubble parameter [Formula: see text]. We have investigated the variation of [Formula: see text] over the observed values of Hubble constant in various observations within the range of redshift [Formula: see text]. Also, we have studied effective energy density [Formula: see text], effective pressure [Formula: see text] and effective EoS parameter [Formula: see text]. We have observed that the second term of [Formula: see text] function behaves just like variable cosmological term [Formula: see text] ([Formula: see text]) at late-time universe and causes the acceleration in expansion and works just like dark energy candidates. Also, we have evaluated the age of the present universe for various stages of matter [Formula: see text] and various [Formula: see text] functions.