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This paper investigates the application of K-means clustering algorithms to traditional aircraft conceptual-level weight estimation techniques. K-Means clustering was utilized as a means for statistical discovery within the dataset to explore potential paths for improved weight estimation using conceptual-level information. As a proof-of-concept demonstration, scope was limited to fuselage basic weight estimation. A variety of weight sources were parsed and curated to produce a large, diverse dataset consisting of 82 separate aircraft. A corresponding new universal fuselage basic weight regression was generated as a baseline for comparison. K-Means clustering was then employed to sort aircraft into groupings based on configuration and topology with an associated weight equation created for each grouping. Configuration-based groupings utilized information such as a high-level abstraction of the structural layout as well as whether the aircraft is a fixed-wing or rotary-wing vehicle. Topology-based groupings utilized information such as landing gear location and possession of a cargo ramp or wing. The configuration-based groupings showed modest improvement compared to the baseline regression which were in turn outperformed by the topology-based regressions across a range of data groupings. Under all conditions, a subset of the data associated with fixed-wing aircraft was shown to be an outlier in regard to error as a result of a large range of weight and speed scales, in addition to possible secondary pressurization impacts. Special treatment of the winged dataset led to further reduction in error based on unique design features. The weight estimation processes explored within this paper present a methodology that leverages machine learning algorithms that can improve and inform existing best practices. [ABSTRACT FROM AUTHOR]

We report on the design of a data acquisition (DAQ) module for a small animal PET camera developed at our institutes. During the design an important guideline was to develop a system which is built up from strictly identical DAQ modules, and which has no built-in hardware limitation on the maximum number of modules. The developed DAQ module comprises of an LSO scintillator crystal block, a position sensitive PMT, analog signal conditioning circuits, a digitizer, an field programmable gate array (FPGA) for digital signal processing, and a communication module through which the collected data are sent to a cluster of computers for postprocessing and storage. Instead of implementing hardware coincidence detection between the modules, we attach a precise time stamp to each event in our design, and the coincidence is determined by the data collecting computers during postprocessing. The digital CFD algorithm implemented in the FPGA gives a time resolution of 2 ns FWHM for real detector signals. Index Terms--Data acquisition (DAQ), digital CFD, Ethernet, PET, small animal.

We report on the design of a small animal PET scanner being developed at our institutes. The existing setup is the first version of the miniPET machine consisting of four detector modules. Each detector module consists of an 8 x 8 LSO scintillator crystal block, a position sensitive photomultiplier, a digitizer including a digital signal processing board and an Ethernet interface board. There is no hardware coincidence detection implemented in the system and coincidence is determined based on a time stamp attached to every event by a digital CFD algorithm. The algorithm is implemented in the digital signal processing board and generates a time stamp with a coincidence resolution of less than 2 ns. The data acquisition system is based on Ethernet network and is highly scalable in size and performance. Index Terms--Ethernet-based data acquisition, FPGA, free running pulse sampling, LSO, positron emission tomography.

Kynurenines have immunomodulatory and neuroactive properties and can influence the central nervous system. Previous studies showed the involvement of the kynurenines in the pathogenesis and progression of neurodegenerative disease. In neurodegenerative disorders, including tauopathies, the tryptophan metabolism is shifted toward neurotoxic agents and the reduction of neuroprotectant products. Astrocyte-derived kynurenic acid serves as a neuroprotectant. However, systemic administration of kynurenic acid is not effective because of low permeability across the blood-brain barrier (BBB). We used a kynurenic acid analog with similar biological activity but higher brain permeability to overcome BBB limitations. In the present study, we used amide derivate of kynurenic acid N-(2-N, N-dimethylaminoethyl)- 4-oxo-1 H-quinoline-2-carboxamid (KYNA-1). We administered KYNA-1 for three months to tau transgenic rats SHR-24 and analyzed the effect on tau pathology and activation of glial cells. Primary glial cell cultures were applied to identify the mechanism of the KYNA-1 effect. KYNA-1 was not toxic to rats after chronic three-month administration. When chronically administered, KYNA-1 reduced hyperphosphorylation of insoluble tau in the brain of transgenic rats. Noteworthily, the plasma total tau was also reduced. We determined that the effect of KYNA-1 on tau pathology was induced through the modulation of glial activation. KYNA-1 inhibited LPS induced activation of astrocytes and induced transformation of microglia to M2 phenotype. We identified that the administration of KYNA-1 reduced tau hyperphosphorylation and neuroinflammation. KYNA-1 may serve as a promising treatment for tauopathies., (Copyright © 2022 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

The uncontrolled development of nanoscale roughness during plasma exposure of polymer surfaces is a major issue in the field of semiconductor processing. In this paper, we investigated the question of a possible relationship between the formation of nanoscale roughening and the simultaneous introduction of a nanometer-thick, densified surface layer that is formed on polymers due to plasma damage. Polystyrene films were exposed to an Ar discharge in an inductively coupled plasma reactor with controllable substrate bias and the properties of the modified surface layer were changed by varying the maximum Ar+ ion energy. The modified layer thickness, chemical, and mechanical properties were obtained using real-time in situ ellipsometry, x-ray photoelectron spectroscopy, and modeled using molecular dynamics simulation. The surface roughness after plasma exposure was measured using atomic force microscopy, yielding the equilibrium dominant wavelength λ and amplitude A of surface roughness. The comparison of measured surface roughness wavelength and amplitude data with values of λ and A predicted from elastic buckling theory utilizing the measured properties of the densified surface layer showed excellent agreement both above and below the glass transition temperature of polystyrene. This agreement strongly supports a buckling mechanism of surface roughness formation. [ABSTRACT FROM AUTHOR]

Tauopathies represent a heterogeneous group of neurodegenerative disorders characterized by abnormal deposition of the hyperphosphorylated microtubule-associated protein tau. Chronic neuroinflammation in tauopathies is driven by glial cells that potentially trigger the disruption of the blood-brain barrier (BBB). Pro-inflammatory signaling molecules such as cytokines, chemokines and adhesion molecules produced by glial cells, neurons and endothelial cells, in general, cooperate to determine the integrity of BBB by influencing vascular permeability, enhancing migration of immune cells and altering transport systems. We considered the effect of tau about vascular permeability of peripheral blood cells in vitro and in vivo using primary rat BBB model and transgenic rat model expressing misfolded truncated protein tau. Immunohistochemistry, electron microscopy and transcriptomic analysis were employed to characterize the structural and functional changes in BBB manifested by neurofibrillary pathology in a transgenic model. Our results show that misfolded protein tau ultimately modifies the endothelial properties of BBB, facilitating blood-to-brain cell transmigration. Our results suggest that the increased diapedesis of peripheral cells across the BBB, in response to tau protein, could be mediated by the increased expression of endothelial signaling molecules, namely ICAM-1, VCAM-1, and selectins. We suggest that the compensation of BBB in the diseased brain represents a crucial factor in neurodegeneration of human tauopathies., Competing Interests: PM, AM, JH, MC, SJ and AK are employees of AXON Neuroscience R&D Services SE and do not own any shares of the company. This does not alter our adherence to PLOS ONE policies on sharing data and materials. The authors declare that they have no other competing interests.

The therapeutic options in systemic sclerosis (SSc) are limited mainly to the management of complications, and decelerating fibrosis and preventing disease progression are still great challenges. Extracorporeal photopheresis (ECP) is one of the promising therapeutic strategies in SSc; nevertheless, there is no consensus on the ideal timing and frequency of treatment cycles. In the present study, we evaluated the long-term effects of consecutive ECP treatments, and the stability of clinical and laboratory improvements. We enrolled nine patients with diffuse cutaneous SSc and performed 12 ECP cycles (24 ECP treatments) per patient in total. ECP cycles were carried out once in every 6 weeks, and each cycle consisted of two procedures. Sixteen healthy individuals served as controls for laboratory assessment. Following the sixth ECP cycle, we observed further improvement in skin score, which was confirmed by high-resolution ultrasonography as well. After the second ECP cycle, values of Tr1 and CD4+CD25(bright) Treg cells increased; however, Tr1 cells remained under control values until the 10th cycle. Suppressor activity of CD4+CD25+ Treg cells improved, while percentages of Th17 cells decreased. At the end of 12-month follow-up, we did not observe significant deterioration in skin involvement; however, improvement in laboratory parameters diminished after 12 months. If the first six ECP cycles are effective, uninterrupted continuation of treatment should be considered, which may lead to the normalization of Tr1 cell values along with further clinical improvement. Our laboratory observations indicate that immunomodulatory effect of ECP treatments lasts for 1 year only.

Background: The Blood-Brain Barrier (BBB) is a complex and dynamic interface that regulates the exchange of molecules and cells between the blood and the central nervous system. It undergoes structural and functional throughout oxidative stress and inflammation, which may compromise its integrity and contribute to the pathogenesis of neurodegenerative diseases. Main body: Maintaining BBB integrity is of utmost importance in preventing a wide range of neurological disorders. NRF2 is the main transcription factor that regulates cellular redox balance and inflammation-related gene expression. It has also demonstrated a potential role in regulating tight junction integrity and contributing to the inhibition of ECM remodeling, by reducing the expression of several metalloprotease family members involved in maintaining BBB function. Overall, we review current insights on the role of NRF2 in addressing protection against the effects of BBB dysfunction, discuss its involvement in BBB maintenance in different neuropathological diseases, as well as, some of its potential activators that have been used in vitro and in vivo animal models for preventing barrier dysfunction. Conclusions: Thus, emerging evidence suggests that upregulation of NRF2 and its target genes could suppress oxidative stress, and neuroinflammation, restore BBB integrity, and increase its protection. [ABSTRACT FROM AUTHOR]

Design and development of novel, low-cost and efficient electrocatalysts for oxygen evolution reaction (OER) in alkaline media is crucial for lowering the reaction overpotential and thus decreasing the energy input during the water electrolysis process. Herein, we present the synthesis of new 14-membered bis-thiosemicarbazide and bis-isothiosemicarbazide macrocycles and their nickel(II) complexes characterized by spectroscopic techniques (1H and 13C NMR, IR, UV–vis), electrospray ionization mass spectrometry, single crystal X-ray diffraction, scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX) and cyclic voltammetry. Finally, the activity of nickel(II) complexes towards OER is reported. NiIILSEt delivered a current density of 10 mA cm−2 at the lowest overpotential of 350 mV with the lowest Tafel slope of 93 mV dec−1. The high performance of NiIILSEt might be attributed to its high surface area and thus abundant active sites with the observed low charge-transfer resistance enabling the effective current flow through the electrocatalyst. Square-planar coordination geometry and increment in Ni oxidation state are believed to favor its OER performance. Beside high activity towards OER, NiIILSEt demonstrated excellent long-term stability with continuous operation, advocating its possible application in commercial systems. [ABSTRACT FROM AUTHOR]

Purpose: In pursuit of objectives, under the European Green Deal, to channel capital flows to sustainable activities, the EU Taxonomy offers clarity, labelling real economic activities as "sustainable", based on technical screening criteria. This study of disclosure experiences aims to explore the role of co-evolutionary relationships in the Taxonomy's effectiveness. Design/methodology/approach: Co-evolution theory implies a dynamic interplay among sustainable finance stakeholders (SFSs), through adjustment to, impact on and operationalisation of the Taxonomy. Corporate disclosure experiences, including those of financial institutions and related SFS experiences, may reveal co-evolutionary processes. With significant Undertakings for Collective Investment in Transferable Securities (UCITS) and Alternative Investment Funds (AIFs), Irish SFSs provide contextual insight. Semi-structured interviews with a purposive sample of Irish SFSs capture inaugural corporate Taxonomy disclosure experiences. Findings: A thematic analysis reveals six co-evolutionary processes that facilitate Taxonomy implementation in pursuit of policy objectives: [1] cross-functional reporting; [2] iterative pre-empting and addressing compliance issues; [3] regulation as a catalyst for co-evolution; [4] advanced capacity building; [5] stakeholder adaptation and [6] graduated use of ESG data. Implications for sustainability policy development and management are significant. Practical implications: Whilst limited to just one EU jurisdiction, given limited prior empirical evidence for sustainable finance regulations from co-evolutionary perspectives, this study highlights a catalytic, yet precautionary role for co-evolution in their transformation effectiveness. As such, they must take account of their potential to stimulate co-evolution and to nurture it in pursuit of their policy objectives. Social implications: The findings of this study add to a small, but growing body of academic literature on the Taxonomy Regulation, which suggests that a co-evolutionary lens is important for gaining a comprehensive understanding of its early-stage dynamics. From an implementation perspective, the qualitative data reveals actionable implications for regulators and policymakers, such as building capacity, better anticipation of outcomes and investment in data infrastructure. Originality/value: Unlike existing analyses of disclosures, this study offers a co-evolutionary lens on Taxonomy contributions to sustainable development through qualitative accounts. [ABSTRACT FROM AUTHOR]

Purpose: New technologies, digitalization tools, and the changing world of work have created a virtual, multicultural, and crossborder environment within organizations. Consequently, a growing body of international business literature is focusing on global virtual teams. However, the research so far has focused more on work-based challenges and outcomes of global virtual teams, with limited attention to long-term trust development between members in these teams. This gap is the key focus of the present research. Design/methodology/approach: In this study, data were collected from 19 interviewees of various nationalities who were part of global virtual teams to understand trust development and identity changes. Afterwards, the NVivo software was used, and findings were generated using the "thematic analysis approach." Findings: The findings suggested that individuals working in global virtual teams perceived that such a work arrangement had a positive effect on their work performance; however, it had several negative consequences for their social and nonwork lives. Further, while many team members were able to develop swift and cognitive trust with their global virtual team members, the development of affective trust was less common. Also, exposure to multicultural team members, albeit remotely, resulted in most of the individuals embracing (perceived positive) changes in their behaviors and attitudes, thus reflecting a gradual move toward globalization of the workforce values, yet simultaneously creating greater uncertainty and complexity in their identity and work values. Originality/value: Using the findings, a novel process model, i.e. "the social identity perspective of trust development in global virtual teams" has been proposed, which offers a step-wise guidance regarding how affect-based trust may be developed in global virtual teams in various stages. [ABSTRACT FROM AUTHOR]