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Xanthan gum modulation of octenyl succinic anhydrate starch-based high internal phase emulsions:Characterization, rheological behavior, and 3D printing applications
Get PDFThe growing popularity of three-dimensional (3D) food printing has highlighted the need for suitable printable materials. This study explores the impact of xanthan gum on octenyl succinic anhydride (OSA) starch-stabilized High Internal Phase Emulsions (HIPEs) for 3D food printing applications. Xanthan gum was added to increase the viscosity of the continuous phase, which helps to slow down the movement and reduce the collision of emulsion droplets. The enhanced rheological properties resulting from the addition of xanthan gum enabled the successful use of OSA-based HIPEs in 3D printing. The formulation containing 0.3 wt% xanthan gum produced accurately detailed printed scaffolds. Furthermore, the study demonstrates improved thermal stability of β-carotene when encapsulated within these HIPEs. These findings provide comprehensive guidelines for formulating starch HIPE inks, presenting a promising method for incorporating diverse hydrophobic molecules in 3D food printing applications.</p
Evaluating the global thiols redox state in living cells using a reducing sulfur species responsive fluorescence switching platform
Get PDFRedox dyshomeostasis is a critical factor in the initiation of numerous diseases, making the accurate evaluation of the redox status of the cellular environment an important aspect of physiological research. However, maintaining redox homeostasis relies on a complex and dynamic physiological system involving multiple substrate-enzyme interactions, so its accurately detection remains a challenge. With this research, we developed an activable fluorescence switching platform by incorporating different conjugate acceptors to a fluorophore using ester bonds and resulting in fluorescence quenching due to donor-excited photo-induced electron transfer (d-PeT), which was confirmed through density functional theory calculations. The reaction-based probe was deployed for recognizing all major intracellular reducing sulfur species (RSS), including H2S, cysteine (Cys), homocysteine (Hcy), glutathione (GSH), and protein free thiols. The quenched fluorescence was significantly recovered by RSS, through releasing the fluorophore and diminishing the d-PeT effect. Furthermore, the fluorescent probe was used for the sensing and imaging RSS in living cells, demonstrating good cell-permeability, low cytotoxicity, and negative correlation with reactive oxygen species content, enabling the evaluating of global thiols redox state in HepG2 cellular lines during ferroptosis processes.</p
Design of a High-Order Mode Corrugated Slow Wave Structure With Large Beam Tunnel for Traveling Wave Tube
Get PDFIn the millimeter wave and terahertz band, the size of vacuum electronic devices becomes small, typically close to the wavelength, which poses a great challenge to manufacturing and assembly. High-order mode operation allows for comparatively larger circuit dimensions at the expense of mode competition. Here, we report on the development of a corrugated slow wave structure (CSWS) that is placed outside the E -plane of the rectangular waveguide. The likely TM11 mode is excited in the CSWS during TE10 -mode excitation, and a high-order hybrid operating mode is achieved. The transmission characteristics of the fundamental mode and high-order hybrid mode in a high-frequency circuit are obtained simultaneously in this Ka-band experiment. As a result of the strong longitudinal electric field component of the hybrid mode in this CSWS, the radius of the beam tunnel can be increased by approximately 60%. Meanwhile, the mode competition can be effectively suppressed with the increase in the size of CSWS. A 1-THz traveling wave tube (TWT) operating near a phase of 505° is designed to compare with the size of the beam tunnel. The diameter of the beam tunnel can reach up to 0.1 mm. The simulation results show that the maximum output power is 1.12 W at 1028 GHz, and the -3-dB bandwidth (BW) is 7 GHz.</p
Triboelectrification Based on the Waste Waterproof Textiles for Multisource Energy Harvesting
Get PDFThe demand for sustainable energy resources to power sensor networks such as consumer electronics, agricultural technologies, digital forest management, and home automation is rapidly increasing. There are sustainability challenges to consider, where waste waterproof textiles are critical to encourage the development of a circular economy in the development of new energy technologies. This present work focuses on the utilization of direct waste waterproof textiles to design two types of triboelectric nanogenerator (TENG), which include a liquid-solid based TENG (L-S TENG) and a flapper-type TENG. The bottom electrode configuration for the L-S TENG and single electric mode working mechanism is considered for the flapper-type TENG. Waste waterproof textiles can lead to a possible expansion of sustainable material for energy harvesters. The raincoat textile-based L-S TENG (L-STENG-R) is able to generate 0.5 V at a tilt angle of 50 degrees and power of 0.41 nW. TENGs based on discarded waterproof textiles are further utilized to demonstrate their phase change sensing, along with wind and water energy harvesting. This approach focus on decreasing waste and lower dependency on traditional resources to support environmentally responsible energy alternatives.</p
A sparse optimization approach to infinite infimal convolution regularization
Get PDFIn this paper we introduce the class of infinite infimal convolution functionals and apply these functionals to the regularization of ill-posed inverse problems. The proposed regularization involves an infimal convolution of a continuously parametrized family of convex, positively one-homogeneous functionals defined on a common Banach space . We show that, under mild assumptions, this functional admits an equivalent convex lifting in the space of measures with values in . This reformulation allows us to prove well-posedness of a Tikhonov regularized inverse problem and opens the door to a sparse analysis of the solutions. In the case of finite-dimensional measurements we prove a representer theorem, showing that there exists a solution of the inverse problem that is sparse, in the sense that it can be represented as a linear combination of the extremal points of the ball of the lifted infinite infimal convolution functional. Then, we design a generalized conditional gradient method for computing solutions of the inverse problem without relying on an a priori discretization of the parameter space and of the Banach space . The iterates are constructed as linear combinations of the extremal points of the lifted infinite infimal convolution functional. We prove a sublinear rate of convergence for our algorithm and apply it to denoising of signals and images using, as regularizer, infinite infimal convolutions of fractional-Laplacian-type operators with adaptive orders of smoothness and anisotropies
The cascading role of leader-induced defensive cognitions and citizenship pressures in navigating employee silence
Get PDFPurpose: The study aims to attain insights into the impact of destructive leadership and citizenship pressures in inducing employee silence through the lens of social exchange and the conservation of resources theory. The research further relies on Friedkin’s attitude-behaviour linkage framework (2010), while taking into account the role of employees’ defensive cognitive evaluations, as against the previously accented emotion-focused explanations.Design/methodology/approach: In order to corroborate the pertinence and contextual relevance of the framework, a survey-based study was conducted with a purposively selected sample of 133 full-time employees from the systemically important banks. The sample size was determined through an a-priori power analysis using G*Power, and the hypothesized serial mediation model was tested using PLS-SEM in SmartPLS v_4.0.Findings: The findings accentuate the significance of destructive leadership in navigating employees’ silence directly and serially through continuance commitment and compulsory citizenship behaviours. The study also underlines that rather than being portrayed as unidimensional outcomes centered on attitudes, employee behaviours ought to be considered contingent retorts under attitude-behaviour cascades.Originality/value: The study contributes to strategic human resource management literature by offering a cognition based explanation for employees’ silence, taking Pakistan’s cultural and contextual orientation into cognizance. Extending on the attitude-behaviour linkage framework, the study provides that attitudes shaped by defensive cognitive evaluations may concurrently foster involuntary (citizenship) as well as voluntary (silence) behaviours
An Adaptively Inexact Method for Bilevel Learning Using Primal-Dual Style Differentiation
Get PDFWe consider a bilevel learning framework for learning linear operators. In this framework, the learnable parameters are optimized via a loss function that also depends on the minimizer of a convex optimization problem (denoted lower-level problem). We utilize an iterative algorithm called `piggyback' to compute the gradient of the loss and minimizer of the lower-level problem. Given that the lower-level problem is solved numerically, the loss function and thus its gradient can only be computed inexactly. To estimate the accuracy of the computed hypergradient, we derive an a-posteriori error bound, which provides guides for setting the tolerance for the lower-level problem, as well as the piggyback algorithm. To efficiently solve the upper-level optimization, we also propose an adaptive method for choosing a suitable step-size. To illustrate the proposed method, we consider a few learned regularizer problems, such as training an input-convex neural network
Mapping commercial practices of the pesticide industry to shape science and policymaking:a scoping review
Get PDFThere is a growing body of evidence for how health harming industries (HHIs) engage in similar practices to influence science and policymaking. However, limited attention has been paid to the pesticide industry within the commercial determinants of health (CDOH) field. We conducted a scoping review to map practices adopted by the pesticide industry to influence science and policymaking and to assess the breadth and focus of the associated literature. We included 31 documents and categorized the extracted data using a typology of commercial practices. The documents described how major pesticide companies, and their trade bodies, have acted to influence science and maintain favourable regulatory environments while undermining the credibility of researchers and agencies that publish findings threatening to their commercial interests. A large proportion of the literature consists of historical analyses, narrative reviews, commentaries/perspective pieces, and investigative reports published in the grey literature, predominantly informed by analysis of internal industry documents and freedom of information requests. Most studies focus on high-income settings. There were a limited number of primary peer-reviewed empirical studies that explicitly aimed to study the practices of the pesticide industry from a CDOH perspective. However, our findings show that major pesticide companies adopt political and scientific practices highly similar to other HHIs. The review shows a critical need for research on the pesticide industry’s current practices in low- and middle-income countries where the negative impacts of its activities on health and the environment are likely to be more marked
Head contact and suspected concussion rates in youth basketball:Time to target head contact penalties for prevention
Get PDFObjective: To compare game events, head contact (HC) rates, and suspected concussion incidence rates (IRs) in boys' and girls' youth basketball.Design: Cross-sectional.Setting: Canadian club basketball teams (U16-U18).Participants: Players from 24 boys' and 24 girls' Canadian club basketball teams during the 2022 season.Assessment of Risk Factors: Recorded games were analyzed using Dartfish video analysis software to compare sexes.Main Outcome Measures: Poisson regression analyses were used to estimate HCs [direct (HC1) and indirect (HC2)], suspected concussion IRs, and IR ratios (IRRs). Game event, court location, and HC1 fouls were reported.Results: Division 1 HC rates did not differ between boys (n = 238; IR = 0.50/10 player-minutes; 95% confidence interval [CI], 0.43-0.56) and girls (n = 220; IR = 0.46/10 player-minutes; 95% CI, 0.40-0.52). Division 2 boys experienced 252 HCs (IR = 0.53/10 player-minutes; 95% CI, 0.46-0.59); girls experienced 192 HCs (IR = 0.40/10 player-minutes; 95% CI, 0.35-0.46). Division 2 boys sustained higher HC1 IRs compared with Division 2 girls (IRR = 1.42; 95% CI, 1.15-1.74). Head contacts, rates did not differ between boys and girls in either Division. Suspected concussion IRs were not significantly different for boys and girls in each Division. Head contacts occurred mostly in the key for boys and girls in each Division. Despite illegality, HC1 penalization ranged from 3.9% to 19.7%. Head contact mechanisms varied across Divisions and sexes.Conclusions: Despite current safety measures, both HCs and suspected concussions occur in boys' and girls' basketball. Despite the illegality and potential danger associated with HC, only a small proportion of direct HCs were penalized and therefore targeting greater enforcement of these contacts may be a promising prevention target
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