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Regioselective C6 and C2,C3 carboxylated cellulose nanofibrils (CNFs) have been robustly generated from dissolving pulp, a readily available source of unmodified cellulose, via stoichiometrically optimized 2,2,6,6-tetramethylpyperidine-1-oxyl (TEMPO)-mediated and sequential sodium periodate-sodium chlorite (PC) oxidation coupled with high-speed blending. Both regioselectively optimized carboxylated CNF series possess the widest ranges of comparable charges (0.72-1.48 mmol/g for T-CNFs vs. 0.72-1.10 mmol/g for PC-CNFs), but similar ranges of thickness (1.3-2.4 nm for T-CNF, 1.8-2.7 nm PC-CNF), widths (4.6-6.6 nm T-CNF, 5.5-5.9 nm PC-CNF), and lengths (254-481 nm T-CNF, 247-442 nm PC-CNF). TEMPO-mediated oxidation is milder and one-pot, thus more time and process efficient, whereas the sequential periodate-chlorite oxidation produces C2,C3 dialdehyde intermediates that are amenable to further chemical functionalization or post-reactions. These two well-characterized regioselectively carboxylated CNF series represent coherent cellulose nanomaterial models from a single woody source and have served as references for their safety study toward the development of a safer-by-design substance evaluation tool.

A new family of stable radical‐containing polytopic ligands based on tris(2‐pyridylmethyl)amines TPMA architecture and their corresponding metal complexes have been synthesized. These molecular systems offered the possibility to investigate how various spin carriers, such as the metal ion and the organic radical, influence their EPR properties mainly through the empirical ratio of peak heights d1/d. Moreover, it has been possible to analyze how different conformations of TEMPO radical units in the molecular skeleton affect the metallic system. [ABSTRACT FROM AUTHOR]

This study examines experimental data on the influence of the surrounding medium and non-covalent interactions on the isotropic hyperfine coupling constant, Aiso(14N), of the stable nitroxide radical 2,2,6,6-Tetramethylpiperidin-1-yl)oxyl (TEMPO) in solution. The data were used to identify a density functional theory functional/basis set combination that accurately reproduces the experimental Aiso(14N) values. The variations in Aiso(14N) due to external factors are two orders of magnitude greater than the accuracy of its experimental measurements, making Aiso(14N) a highly sensitive experimental probe for quantifying these effects. Additionally, it was found that the proton-accepting ability of the N-O• moiety in TEMPO resembles that of the P=O moiety, enabling the simultaneous formation of two equally strong hydrogen bonds. [ABSTRACT FROM AUTHOR]

X-Ray micro-computed tomography (XCT) is used to reveal the micro-structural changes of banana pseudostem nanocellulose bioplastic due to a biodegradation process initiated in a formulated composting media that allowed the growth of aerobic microflora. The bioplastic itself was made of nanocellulose, which was isolated from banana pseudostem using the 2,2,6,6-Tetramethyl-1-piperidinyloxy (TEMPO) mediated oxidation method, and polyethylene glycol (PEG) as plasticiser. XCT provided insights into the 3D structural change of the bioplastic identifying the degradation process at two scales. The results showed that the local thickness and roughness of the bioplastic increased after degradation, while the density of the material decreased. Enlarged voids and tunnels were observed in the material after degradation. The formation of these tunnels is attributed to the popping of internal PEG-containing voids because of the generation of gases, which after forming may further accelerate biodegradation by microbial activity. [ABSTRACT FROM AUTHOR]

Copyright of Logopedia e Comunicazione is the property of Edizioni Centro Studi Erickson SpA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract X-Ray micro-computed tomography (XCT) is used to reveal the micro-structural changes of banana pseudostem nanocellulose bioplastic due to a biodegradation process initiated in a formulated composting media that allowed the growth of aerobic microflora. The bioplastic itself was made of nanocellulose, which was isolated from banana pseudostem using the 2,2,6,6-Tetramethyl-1-piperidinyloxy (TEMPO) mediated oxidation method, and polyethylene glycol (PEG) as plasticiser. XCT provided insights into the 3D structural change of the bioplastic identifying the degradation process at two scales. The results showed that the local thickness and roughness of the bioplastic increased after degradation, while the density of the material decreased. Enlarged voids and tunnels were observed in the material after degradation. The formation of these tunnels is attributed to the popping of internal PEG-containing voids because of the generation of gases, which after forming may further accelerate biodegradation by microbial activity.

There are few studies on the extraction of bioactive compounds from olive pomace by the microwave method of hydro diffusion and gravity (MHG). Therefore, this study extracted bioactive compounds from pomace by MHG using a central rotational compound (DCCR). The statistical model showed a significant difference for the variable potency (W) in the extractions of phenolic compounds, showing linear behavior. Simple linear regression analysis suggested the use of 100W of power for the extraction of phenolic compounds in olive pomace. There were no significant differences in flavonoid extractions and antioxidant capacity of the extracts, at different potencies (W) and times (min), in the olive pomace extracts. [ABSTRACT FROM AUTHOR]

The practice of using wind and solar energy to generate electricity represents a solution that would be beneficial for the environment and ought to be explored. However, in order to ensure users' stability and continuous access to electricity, the increasing usage of renewable energy needs to align with the advancement of energy storage technologies. Redox flow batteries, which use an organic solution as the electrolyte and a proton exchange membrane as an ion exchange layer, are currently the subject of extensive research as one of the alternative renewable energy storage systems with the benefit of a techno economy. This study investigated the solubility of organic solution, namely 2,2,6,6-Tetramethylpiperidinyloxy or 2,2,6,6-Tetramethylpiperidine 1-oxyl (TEMPO) and methyl viologen (MV) in various essential electrolyte solutions such as NaCl, KCl, KOH, and H2SO4 that can be used as electrolytes of all organic redox flow battery (AORFB) system to produce high energy density and charging and discharging capacity. The result shows the optimum condition for effective charge transfer in AORFB is TEMPO catholyte and MV anolytes in the 0.08 M H2SO4electrolyte solution. Additionally, a correlation between the acquisition of electrolyte solutions on TEMPO catalyst and MV anolytes was discovered by the data. Electrolyte solution can improve electrical conductivity in TEMPO solution, which in turn can improve the efficiency of AORFB charging and discharging. Contrarily, MV anolytes exhibit a different pattern where the addition of electrolyte solutions reduces their electrical conductivity. RFBs systems with the aforementioned catholyte and anolyte can be used to store solar energy with a maximum current of 0.6 A for 35 minutes. Storage effectiveness is characterized by a change in colour in the catholyte and anolyte. The findings firming the possibility of using AORFB as one of the alternative energy storage systems that can accommodate the intermittence of the renewable energy input resource.

This paper describes a model for thinking of how participants make sense of temporal aspects of their lived experience. The paper argues for the valuable input that interpretative phenomenological analysis (IPA) can make to exploring this experiential timeline. After a brief introduction to IPA as an experiential research methodology, I will describe the growing interest in longitudinal research among qualitative researchers and outline recent thinking on this by leading researcher Bren Neale. I will then point to the distinctive contribution IPA can make to understanding personal experience of time and change. I will present a taxonomy of my IPA research engaging with it and illustrate each study type with research I have been involved in. During the paper we will see the way in which there are indeed two time-travelers involved in this process: researcher and the participant. [ABSTRACT FROM AUTHOR]

Methyl and benzyl (ethyl 3,4-di-O-benzyl-2-O-benzoyl-1-thio-β-D-glucopyranosyl)uronate were synthesised from a protected thioglycoside in three steps. A regioselective ring opening of the benzylidene acetal with BH3.THF generated C6-OH material, which was subsequently oxidised using biphasic TEMPO/BAIB conditions. The resultant uronic acid was esterified with either a methyl or benzyl moiety. The products were obtained on a multigram scale and fully characterised by 1H, 13C and 2D NMR, alongside MS and IR analysis. [ABSTRACT FROM AUTHOR]

Ischemia– reperfusion (I/R) injury-induced oxidative stress is a key factor in the pathogenesis of pressure ulcer formation. Ferroptosis is an iron-dependent programmed cell death that connects oxidative stress and inflammation in various diseases. Recent studies revealed the protective effect of inhibition of ferroptosis in I/R injury. However, the role of ferroptosis in cutaneous I/R injury remains elusive. To assess the role of ferroptosis in the progression of cutaneous I/R injury. Cutaneous I/R injury experiments and histopathological studies were performed in wild-type mice with or without exposure to volatile ferroptosis inhibitor, TEMPO (2,2,6,6-Tetramethylpiperidine-1-oxyl). The suppressive effects of TEMPO on ferroptosis inducing cell death and oxidative stress were examined in vitro. Inhibition of ferroptosis with TEMPO significantly reduced ulcer formation after cutaneous I/R injury. Fluctuated ferroptosis markers, such as GPX4, ACSL4, and 4-HNE expression in the I/R skin site, were reversed by TEMPO treatment. Inhibition of ferroptosis reduced apoptosis, CD3+ infiltrating lymphocytes, and improved vascularity in the I/R skin site. Inhibition of ferroptosis also suppressed the enhancement of Nrf2 activation. In vitro , ferroptosis and the activation of ferroptosis-related gene expression by RSL3 stimulation were markedly ameliorated by TEMPO treatment in mouse fibroblasts. Inhibiting ferroptosis also suppressed the elevation of the mRNA levels of NOX2 and HO-1 caused by ferroptosis. Cutaneous I/R injury-induced ferroptosis likely promotes cell death, vascular loss, infiltration of inflammatory cells, and oxidative stress. The inhibition of ferroptosis with TEMPO might have potential clinical application as novel therapeutic agent for cutaneous I/R injury. • Cutaneous I/R injury induced ferroptosis in wound area. • Inhibition of ferroptosis by TEMO suppressed PUs after cutaneous I/R injury. • Inhibition of ferroptosis reduced oxidative stress after cutaneous I/R injury. • Oxidative stress and cell death caused by ferroptosis was improved by TEMPO. [ABSTRACT FROM AUTHOR]

Copyright of European Journal of Psychotherapy & Counselling is the property of Routledge and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Musicians have long sought technology to facilitate and develop their abilities to maintain stable tempos. The rise of inherently tempo-stable instruments and performance technologies in the late 20th century—for example, turntables, sequencers, drum machines, click tracks, and post-production quantization—has fed an increasing trend toward tempo stability in Western popular music. However, the exact progression of this historical change has not been systematically documented. In this article, we report a historical analysis of tempo stability in recordings of Western Classical and Anglo-American popular music released between 1920 and 2020, in particular testing the hypothesis that tempo in certain popular genres became significantly more stable in the period 1980–2000. We distinguish between gradual changes of tempo that are not perceived as discontinuities (tempo drift) and abrupt changes of tempo (tempo shifts), and seek to quantify both types of tempo instability. Using the Spotify web API, we sampled measure-by-measure tempo estimates from over 45,000 tracks in seven genres: Blues, Classical, Country, Electronic Dance Music (EDM), Hip hop, Jazz, and Rock. Our analyses reveal significant changes in tempo stability in Rock, Country, and Blues music, consistent with our hypothesis. We next propose, compare, and evaluate several approaches to identifying artificially tempo-stable tracks from their tempo estimates, using the opposition between Classical and Hip hop as a faux ground truth. Data, analyses, and interactive visualizations are available for inspection on our website https://ccml.music.gatech.edu/TempoStability. [ABSTRACT FROM AUTHOR]

We report an iron‐catalyzed decarboxylative C(sp3)−O bond‐forming reaction under mild, base‐free conditions with visible light irradiation. The transformation uses readily available and structurally diverse carboxylic acids, iron photocatalyst, and 2,2,6,6‐tetramethylpiperidine 1‐oxyl (TEMPO) derivatives as oxygenation reagents. The process exhibits a broad scope in acids possessing a wide range of stereoelectronic properties and functional groups. The developed reaction was applied to late‐stage oxygenation of a series of bio‐active molecules. The reaction leverages the ability of iron complexes to generate carbon‐centered radicals directly from carboxylic acids by photoinduced carboxylate‐to‐iron charge transfer. Kinetic, electrochemical, EPR, UV/Vis, HRMS, and DFT studies revealed that TEMPO has a triple role in the reaction: as an oxygenation reagent, an oxidant to turn over the Fe‐catalyst, and an internal base for the carboxylic acid deprotonation. The obtained TEMPO adducts represent versatile synthetic intermediates that were further engaged in C−C and C‐heteroatom bond‐forming reactions using commercial organo‐photocatalysts and nucleophilic reagents. [ABSTRACT FROM AUTHOR]

An ionic heterogenized catalyst system for Anelli oxidation has been developed using potassium 4-sulfonato-oxy-2,2,6,6-tetramethylpiperidine-1-yloxyl (TEMPO-4-sulfate) and anion exchange beads as support material. The catalytic oxidation of benzyl alcohol by bis(acetoxy)iodobenzene (BAIB) in acetonitrile with the modified beads gives a 94% yield of benzaldehyde within 60 min (batch operation). The beads give about the same conversion of benzyl alcohol in six consecutive cycles when reused after simple washing, albeit with a somewhat longer half-life time. The TEMPO entity could be removed from the beads using a sodium chloride/sodium hydroxy mixture. Reloading the beads with TEMPO-4-sulfate restored about 80% of their initial catalytic action. This exemplifies that the catalytic activity in a fixed bed can be regained without the need for cleaning and repacking the reactor. Preliminary experiments in a fixed bed show that a constant benzyl alcohol conversion of 84% over 10 residence times (as plug flow) can be achieved by the in-flow execution of the oxidation reaction. [ABSTRACT FROM AUTHOR]

Redox‐conducting polymers based on SalEn‐type complexes have attracted considerable attention due to their potential applications in electrochemical devices. However, their charge transfer mechanisms, physical and electrochemical properties remain unclear, hindering their rational design and optimization. This study aims to establish the influence of monomer geometry on the polymer's properties by investigating the properties of novel nonplanar SalEn‐type complexes, poly[N,N'‐bis(salicylidene)propylene‐2‐(hydroxy)diaminonickel(II)], and its analog with 2,2,6,6‐tetramethylpiperidinyl‐N‐oxyl (TEMPO)‐substituted bridge (MTS). To elucidate the charge transfer mechanism, operando UV–Vis spectroelectrochemical analysis, electrochemical impedance spectroscopy, and electron paramagnetic resonance are employed. Introducing TEMPO into the bridge moiety enhanced the specific capacity of the poly(MTS) material to 95 mA h g−1, attributed to TEMPO's and conductive backbone's charge storage capabilities. Replacement of the ethylenediimino‐bridge with a 1,3‐propylenediimino‐ bridge induced significant changes in the complex geometry and material's morphology, electrochemical, and spectral properties. At nearly the same potential, polaron and bipolaron particles emerged, suggesting intriguing features at the overlap point of the electroactivity potentials ranges of polaron–bipolaron and TEMPO, such as a disruption in the connection between TEMPO and the conjugation chain or intramolecular charge transfer. These results offer valuable insights for optimizing strategies to create organic materials with tailored properties for use in catalysis and battery applications. [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The purpose of this study was to determine the effects of model recordings on undergraduate conductors' tempo decisions for selected wind band excerpts. Participants (N = 42) studied three music score excerpts for 5 minutes each either (a) with an increased-tempo recording, (b) with a decreased-tempo recording, or (c) with a metronome set to the faster, printed tempo in the score, followed by a tapping task to demonstrate their preferred tempo. Participants returned 48 hours after their score study session for retention testing in the form of a second tapping task. Results indicated that for two of the three pieces, participants tapped faster in response to the metronome compared to both the decreased- and increased-tempo model recordings. Participants' tempo choices at the first testing session were most often not significantly different than the tempos they heard during study. However, we found that participants' preferred tempos did not vary as a function of study conditions during the retention testing session that occurred 48 hours later, where tempos trended toward moderation across all three musical selections. We speculate that pedagogical recommendations to avoid using model recordings may have limited empirical support, at least among novice conductors and at least in terms of possible long-term effects from short-term use. [ABSTRACT FROM AUTHOR]

Manual hand dexterity involves highly coordinated hand motions for completion of specific tasks, which is crucial for various military activities such as hand-to-hand combat and practical drills. This response is usually a learned behaviour and can be influenced by the body's physiological responses to external stimuli such as background music. In this study, the effect of background music tempo on manual hand dexterity was investigated. A total of 50 male subjects aged 18 to 26 years were administered a manual hand dexterity test with a Purdue Pegboard under three conditions: no background music, slow-tempo classical music and fast-tempo classical music. The order of the music conditions was determined randomly. Mean dexterity values for no music, slow-tempo classical music and fast-tempo classical music were 51.34 ± 6.26, 50.30 ± 6.34 and 52.32 ± 6.82 respectively. Repeated measures ANOVA followed by post-hoc analysis for Bonferroni correction showed no statistically significant differences between the three music conditions, indicating that manual hand dexterity is not affected by different types of background music. The main finding of this study is that listening to slow- and fast-tempo music did not have statistically significant effect on manual dexterity scores among the subjects. This indicates that other factors such as familiarisation, rhythmic auditory stimulation and sufficient time are needed concurrently for the effects to be prominent. [ABSTRACT FROM AUTHOR]

Este artigo parte de uma questão apresentada em debates do Grupo de Pesquisa de Fotografia da Intercom, em 2020, sobre o tempo de observação de uma fotografia. Dessa forma, buscamos refletir sobre o tempo do olhar diante de uma imagem e o que ele pode comunicar a partir do sujeito que observa e se relaciona com a foto. Apresentamos autores como Maurício Lissovsky, Boris Kossoy e Roland Barthes e realizamos uma leitura flutuante da série É o trem do diabo, de Cláudia Andujar. Por fim, entendemos que o tempo contemplativo é fundamental para a afetividade que chama o olhar, comunicando aspectos presentes na subjetividade do observador, não sendo possível apreender o Outro em sua totalidade.

Este artigo discute a confluência entre os tempos de lazer e trabalho em uma unidade prisional a partir de uma pesquisa de campo realizada na Penitenciária Professor Jason Soares Albergaria, situada no município de São Joaquim de Bicas/MG. O objetivo do trabalho foi descrever e analisar as possibilidades de lazer por mulheres trans em contexto de privação de liberdade, como são realizadas e organizadas as atividades e como os espaços são apropriados por elas. O estudo baseou-se na combinação entre pesquisas bibliográfica e de campo, realizada na unidade prisional, com emprego da observação direta, oportunidade em que foi possível conhecer os espaços e visualizar as interações sociais que nela ocorriam. Em seguida, realizou-se grupos focais buscando nas conversas extrair das participantes os sentidos que atribuem ao lazer, suas demandas nessa área, impactos e carências. Observou-se que certas atividades, ora são percebidas como tempo de lazer, ora reivindicadas como tempo de trabalho. Em uma unidade prisional, rompe-se com uma lógica dicotômica entre os tempos entre lazer e trabalho, fenômenos que se entrecruzam no mesmo tempo e espaço.

A criatividade é geralmente retratada como um fator X responsável pela geração espontânea do absolutamente novo. No entanto, a obsessão pela novidade implica uma atenção aos produtos finais e uma atribuição retrospectiva das suas formas a ideias sem precedentes na mente dos indivíduos, ignorando os potenciais geradores de forma das relações e processos em que as pessoas e coisas surgem e se desenvolvem. Nesses processos, espera-se tipicamente que o aprendiz copie as obras dos grandes mestres do passado. No entanto, mesmo seguindo um roteiro ou uma partitura, cada praticante tem de improvisar o seu próprio caminho através do conjunto de tarefas que a performance implica. Com exemplos da música, da caligrafia e da confecção de rendas, mostro que as fontes da criatividade não estão na cabeça das pessoas, mas em seu envolvimento em um mundo em formação. Nesse tipo de criatividade, mais vivenciada que realizada, a imaginação não é tanto a capacidade de apresentar novas ideias, mas o impulso aspiracional de uma vida que não apenas se vive, mas se conduz. Para onde ela é conduzida, no entanto, não é dado de antemão. Abrindo-se ao desconhecido, se expondo, a imaginação conduz não pela maestria, mas pela submissão. Assim, a criatividade do vivenciar, da ação sem agência, é a criatividade da própria vida.

Abstract This study examined the impact of acid hydrolysis, tempo oxidation, and mechanical grinding on the physical, thermal, and structural properties of α-chitin nanocrystals and nanofibers. The manufacturing methods could influence the diameter, functional groups, and crystal patterns of the resulting nanoparticles. Analysis of the DLS results revealed that the size of acidic nanocrystals were smaller and showed improved dispersibility. The XRD patterns indicated that the chemical and mechanical treatments did not alter the crystalline arrangement of the α-chitin. FT-IR spectra analysis revealed that the chemical and mechanical methods did not affect the functional groups of the nanoparticles. DSC results showed that the nanoparticles had good thermal stability up to 400 °C, and it was found that the nanofibers had better thermal resistance due to their longer length. In the FE-SEM images, the nanoparticles were observed as fiber mats with a length of more than 100 nm. It was also found that the diameter of the nanoparticles was less than 100 nm.

The investigation and clarification of the properties of surface-functionalized superparamagnetic nanoparticles in a biological environment are key challenges prior to their medical applications. In the present work, electron paramagnetic resonance spectroscopy (EPR) combined with the spin labeling technique was utilized to better understand the behavior of nitroxides attached to magnetite nanoparticles dispersed in body fluid. EPR spectra of spin-labeled, silane-coated Fe3O4 nanoparticles in human serum and whole blood were recorded and analyzed for both room- and low-temperature values. In all cases, the obtained EPR signal consisted of a broad line from magnetite cores and a characteristic signal from the attached 4-Amino-2,2,6,6-tetramethylpiperidine-1-oxyl (4-amino-TEMPO). Even for liquid samples, the anisotropic components of magnetic tensors did not fully average out, which was reflected in the differences in the intensity of three narrow hyperfine lines from nitroxide. At 230 K the irregular slow-motion signal from the attached radical was also simulated using the EasySpin toolbox, which allowed to determine the parameters related to magnetic tensors and the dynamics of the spin label. The study showed that the anisotropy of the motion of the spin label 4-amino-TEMPO reflects its interactions with the surrounding medium and the manner of the attachment of the nitroxide to the surface of nanoparticles.

Abstract The study investigates the molecular structure of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) and its derivatives in the gas phase using B3LYP and M06-2X functional methods. Intermolecular interactions are analyzed using natural bond orbital (NBO) and atoms in molecules (AIM) techniques. NO2-substituted TEMPO displays high reactivity, less stability, and softer properties. The study reveals that the stability of TEMPO derivatives is mainly influenced by LP(e) → σ ∗ electronic delocalization effects, with the highest stabilization observed on the oxygen atom of the nitroxide moiety. This work also considers electron density, atomic charges, and energetic and thermodynamic properties of the studied NO radicals, and their relative stability. The proton affinity and gas-phase basicity of the studied compounds were computed at T = 298 K for O-protonation and N-protonation, respectively. The studied DFT method calculations show that O-protonation is more stable than N-protonation, with an energy difference of 16.64–20.77 kcal/mol (22.80–25.68 kcal/mol) at the B3LYP (M06-2X) method. The AIM analysis reveals that the N–O…H interaction in H2O complexes has the most favorable hydrogen bond energy computed at bond critical points (3, − 1), and the planar configurations of TEMPO derivatives exhibit the highest EHB values. This indicates stronger hydrogen bonding interactions between the N–O group and water molecules.

Embryo development is a dynamic process governed by the regulation of timing and sequences of gene expression, which control the proper growth of the organism. Although many genetic programmes coordinating these sequences are common across species, the timescales of gene expression can vary significantly among different organisms. Currently, substantial experimental efforts are focused on identifyingmolecular mechanisms that control these temporal aspects. In contrast, the capacity of established mathematical models to incorporate tempo control while maintaining the same dynamical landscape remains less understood. Here, we address this gap by developing a mathematical framework that links the functionality of developmental programmes to the corresponding gene expression orbits (or landscapes). This unlocks the ability to find tempo differences as perturbations in the dynamical system that preserve its orbits. We demonstrate that this framework allows for the prediction of molecular mechanisms governing tempo, through both numerical and analytical methods. Our exploration includes two case studies: a generic network featuring coupled production and degradation, with a particular application to neural progenitor differentiation; and the repressilator. In the latter, we illustrate how altering the dimerisation rates of transcription factors can decouple the tempo from the shape of the resulting orbits. We conclude by highlighting how the identification of orthogonal molecular mechanisms for tempo control can inform the design of circuits with specific orbits and tempos. [ABSTRACT FROM AUTHOR]

Biomass‐derived 5‐hydroxymethyl furfural (5‐HMF) is a promising starting substrate for producing two high value‐added products 2,5‐diformylfuran (DFF) and 2,5‐furandicarboxylic acid (FDCA). DFF, which is produced by selectively oxidizing the hydroxymethyl group of 5‐HMF to an aldehyde group, has many applications in pharmaceuticals, macrocyclic ligands and fluorescent materials. Oxidizing both aldehyde and hydroxymethyl groups of 5‐HMF leads to FDCA, which is an important monomer in the production of a bioplastic polyethylene furanoate polymer. Electrochemical conversion of 5‐HMF is a potential route for sustainable chemical production of DFF and FDCA. In fact, using 2,2,6,6‐tetramethyl‐ piperidine‐1‐oxyl (TEMPO) as a redox mediator leads to a highly efficient and selective electro‐oxidation of 5‐HMF into FDCA in a basic buffer solution. In this report, the direct and TEMPO‐mediated electro‐oxidation of 5‐HMF was investigated in various organic and hydro‐organic media at room temperature. Direct electro‐oxidation leads to a low selective conversion of 5‐HMF to DFF (10 % of yield) and the formation of unwanted products such as formic acid and protoanemonin (90 % and 37 % of yield respectively) in acetonitrile. Electrocatalytic 5‐HMF conversion in the presence of TEMPO as a redox mediator achieved a near‐quantitative yield of DFF in acetonitrile and γ‐valerolactone. Importantly, we demonstrate the role of water in the conversion of aldehydes to carboxylic acids. [ABSTRACT FROM AUTHOR]

The search for common characteristics between the musical abilities of humans and other animal species is still taking its first steps. One of the most promising aspects from a comparative point of view is the analysis of rhythmic components, which are crucial features of human communicative performance but also well-identifiable patterns in the vocal displays of other species. Therefore, the study of rhythm is becoming essential to understand the mechanisms of singing behavior and the evolution of human communication. Recent findings provided evidence that particular rhythmic structures occur in human music and some singing animal species, such as birds and rock hyraxes, but only 2 species of nonhuman primates have been investigated so far (Indri indri and Hylobates lar). Therefore, our study aims to consistently broaden the list of species studied regarding the presence of rhythmic categories. We investigated the temporal organization in the singing of 3 species of crested gibbons (Nomascus gabriellae, Nomascus leucogenys , and Nomascus siki) and found that the most prominent rhythmic category was isochrony. Moreover, we found slight variation in songs' tempo among species, with N. gabriellae and N. siki singing with a temporal pattern involving a gradually increasing tempo (a musical accelerando), and N. leucogenys with a more regular pattern. Here, we show how the prominence of a peak at the isochrony establishes itself as a shared characteristic in the small apes considered so far. [ABSTRACT FROM AUTHOR]

Teaching music often focuses on developing musical concepts, through comparisons and discriminations. This paper contributes to the discussion on concept development in music through recognition of common elements in a situation and a shift from a local to a general level, considering theoretical approaches to mathematical generalisation. It sets to explore preschool children's understanding of tempo and its use in new musical situations. The research involved a musical intervention in six preschool classrooms. Critical incidences from focus group discussions and non-participant observation recorded children's understanding of tempo from their musical actions, drawings, responses and reflection to teacher questions. The findings highlight that children could go beyond the specific content of the activities and focus on the basic characteristics of tempo, integrating them into their song creations. A teaching approach oriented to generalisation through concept development can assist teachers to elaborate musical content and realise students' level of understanding. [ABSTRACT FROM AUTHOR]

Copyright of Revista Ciência & Saúde Coletiva is the property of Associacao Brasileira de Pos-Graduacao em Saude Coletiva and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The investigation and clarification of the properties of surface-functionalized superparamagnetic nanoparticles in a biological environment are key challenges prior to their medical applications. In the present work, electron paramagnetic resonance spectroscopy (EPR) combined with the spin labeling technique was utilized to better understand the behavior of nitroxides attached to magnetite nanoparticles dispersed in body fluid. EPR spectra of spin-labeled, silane-coated Fe3O4 nanoparticles in human serum and whole blood were recorded and analyzed for both room- and low-temperature values. In all cases, the obtained EPR signal consisted of a broad line from magnetite cores and a characteristic signal from the attached 4-Amino-2,2,6,6-tetramethylpiperidine-1-oxyl (4-amino-TEMPO). Even for liquid samples, the anisotropic components of magnetic tensors did not fully average out, which was reflected in the differences in the intensity of three narrow hyperfine lines from nitroxide. At 230 K the irregular slow-motion signal from the attached radical was also simulated using the EasySpin toolbox, which allowed to determine the parameters related to magnetic tensors and the dynamics of the spin label. The study showed that the anisotropy of the motion of the spin label 4-amino-TEMPO reflects its interactions with the surrounding medium and the manner of the attachment of the nitroxide to the surface of nanoparticles. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the effect of step load in hypoxia on the effectiveness of preoperative rehabilitation (PR) and hormone levels based on a case study. Introduction: We assessed the impact of variables such as rate of movement and time under tension (TUT) in normobaric hypoxia on the levels of growth hormone (GH), insulin-like growth factor 1 (IGF-1), and erythropoietin (EPO). Additionally, the impact of step load on the hypertrophy and strength of knee extensors and flexors was assessed. Methods: The work uses a case study, the research subject of which was a 23-year-old female professional handball player. The tests included an isokinetic assessment of the peak torque of knee extensors and flexors as well as body composition analysis. Results: The results showed a more than (10.81-fold) increase in GH after the microcycle with time under tension (TUT). The deficit between the lower limbs was also reduced. Conclusions: Using a hypoxic environment based on an appropriate altitude, combined with changes such as a short rest break between sets and a controlled tempo of movement with an eccentric phase, TUT may offer an alternative to the PR process, especially among athletes who care about fast RTS. [ABSTRACT FROM AUTHOR]

Long-term electrolyses of glucose in a potassium carbonate (K2CO3) aqueous electrolyte have been performed on graphite felt electrodes with TEMPO as a homogeneous catalyst. The influences of the operating conditions (initial concentrations of glucose, TEMPO, and K2CO3 along with applied anode potential) on the conversion, selectivity toward gluconate/glucarate, and faradaic efficiency were assessed first. Then, optimizations of the conversion, selectivity, and faradaic efficiency were performed using design of experiments based on the L9 (34) Taguchi table, which resulted in 84% selectivity toward gluconate with 71% faradaic efficiency for up to 79% glucose conversion. Side products such as glucaric acid were also obtained when the applied potential exceeded 1.5 V vs. reversible hydrogen electrode. [ABSTRACT FROM AUTHOR]

This theoretical essay aims to discuss how the temporalities of different accelerations can contribute to thinking about the space and curricula of contemporary schools. To achieve this, the work was divided into three parts. In the first, the concept of acceleration and its effects on the subjective dimension were presented using arguments arising from the field of Psychology. In the second, acceleration was investigated and how it has figured in the temporalities characteristic of contemporary times. In the third, an analytical distinction was drawn between the modern school and the contemporary school in order to verify the effects of temporalities on school curricula. From these analyses, it was concluded that the temporal experience of acceleration is produced by neoliberalism and has effects on the processes of subjectivation through temporal government. It was verified the existence of multiple temporalities, accelerated and decelerated, which are driven by the competition typical of neoliberalism and coexist in the social world and in our subjectivity. In relation to contemporary schools, it was noticed that their curricula have been constituted by accelerated temporalities that have synchronized and desynchronized forms. Finally, the thesis was demonstrated that both the norm of conduct and the neoliberal subjectivation model can be understood from a temporal perspective that produces effects in contemporary schools. [ABSTRACT FROM AUTHOR]

The study investigates the molecular structure of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) and its derivatives in the gas phase using B3LYP and M06-2X functional methods. Intermolecular interactions are analyzed using natural bond orbital (NBO) and atoms in molecules (AIM) techniques. NO2-substituted TEMPO displays high reactivity, less stability, and softer properties. The study reveals that the stability of TEMPO derivatives is mainly influenced by LP(e) → σ∗ electronic delocalization effects, with the highest stabilization observed on the oxygen atom of the nitroxide moiety. This work also considers electron density, atomic charges, and energetic and thermodynamic properties of the studied NO radicals, and their relative stability. The proton affinity and gas-phase basicity of the studied compounds were computed at T = 298 K for O-protonation and N-protonation, respectively. The studied DFT method calculations show that O-protonation is more stable than N-protonation, with an energy difference of 16.64–20.77 kcal/mol (22.80–25.68 kcal/mol) at the B3LYP (M06-2X) method. The AIM analysis reveals that the N–O...H interaction in H2O complexes has the most favorable hydrogen bond energy computed at bond critical points (3, − 1), and the planar configurations of TEMPO derivatives exhibit the highest EHB values. This indicates stronger hydrogen bonding interactions between the N–O group and water molecules. [ABSTRACT FROM AUTHOR]

Herein, we present a photoinduced deconstructive alkoxyamination of alkyl alcohols catalyzed by iron salts. This transformation involves the initiation of alkoxy radicals through chlorine radical‐induced alkoxy radical formation, followed by β‐scission and trapping of the resulting carbon radicals with 2,2,6,6‐tetramethylpiperidin‐1‐yl (TEMPO). This reaction exhibits a broad substrate scope (40 examples), including primary and secondary alcohols that are prone to oxidation by the combination of TEMPO and iron. Mechanistic investigations have revealed that enhanced coordination of the chloride ion with the iron center inhibits the OH oxidation process, thereby enabling the tolerance of primary and secondary alcohols. [ABSTRACT FROM AUTHOR]

Understanding of how time is experienced is essential when conducting qualitative research. This article explores how time seemingly stands still, speeds up, slows down, rewinds and fast-forwards for the participants in our qualitative investigations. Drawing upon interview data with street homeless people in Moscow, Russia, this article examines the ways in which time is contextualized and used by research participants to make sense of their everyday experiences and important events in their lives. There is a tendency to understand time by measuring it, rather than seeing it as something within which lived experience happens and qualitative research is carried out. Drawing on Bergson's conception of time as duration, this article examines the ways in which time can be distinctively used and understood within qualitative research. [ABSTRACT FROM AUTHOR]

To describe the duration, timing, tempo, and synchronicity of puberty, as well as the correlation between timing and tempo of puberty. Overall, 15,819 of 22,439 invited children participated in the Puberty Cohort within the Danish National Birth Cohort. Participants completed a web-based questionnaire every 6 months through maturation with questions on current pubertal status. Girls reported current Tanner stage of breast and pubic hair development, and timing of menarche. Boys reported current Tanner stage of genital and pubic hair development, timing of first ejaculation, and vocal changes. While accounting for this interval-censored puberty information, we estimated the duration of puberty. Then, we used a nonlinear mixed effect growth model to estimate timing, tempo, synchronicity of puberty, and correlation between timing and tempo of puberty. In girls, the average duration of breast development was longer, whereas the average tempo was slower than pubic hair development. The average timing of breast development was earlier than the average timing of pubic hair development. The majority of girls had asynchronous puberty. In boys, the average duration was longer and average tempo slower for genital than pubic hair development. The average timing of genital and pubic hair development were comparable; hence, the majority had synchronous pubertal development. Adolescents who had earlier timing also tended to have a faster tempo. Being one of the largest puberty cohorts worldwide, these unique contemporary data can help physicians, parents, and children to understand and anticipate expected progression through pubertal development. [ABSTRACT FROM AUTHOR]

Current knowledge of the characteristics of puberty beyond age at menarche and thelarche is limited, particularly within population-based cohorts. Secular trends and concerns of the health effects of early puberty reinforce the value of contemporary studies characterizing the timing, tempo, duration, and synchronicity of puberty. The Childhood to Adolescence Transition Study is a unique Australian cohort of individuals followed annually from late childhood to late adolescence, with up to eight assessments of pubertal stage from 9 to 19 years of age (N = 1,183; 636 females). At each assessment, females reported their Tanner Stage of breast and pubic hair development, while males reported on genital/pubic hair development. Nonlinear mixed-effects models characterized pubertal trajectories and were used to derive each individual's estimates of timing, tempo, and synchronicity. Parametric survival models were used to estimate the overall duration of puberty. Timing of mid-puberty (Tanner Stage 3) ranged from 12.5 to 13.5 years, with females developing approximately 6 months before males. Pubertal tempo (at mid-puberty) was similar across sex (between half and one Tanner Stage per year), but the overall duration of puberty was slightly shorter in males. Most females exhibited asynchronous changes of breast and pubic hair development. Estimates of pubertal timing and tempo are consistent with reports of cohorts from two or more decades ago, suggesting stabilization of certain pubertal characteristics in predominantly White populations. However, our understanding of the duration of puberty and individual differences in pubertal characteristics (e.g., synchronicity of physical changes) remains limited. [ABSTRACT FROM AUTHOR]