Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 521
Filter
1.
Small ; : e2405698, 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39263767

ABSTRACT

Inherent luminescent short peptides essentially provide opportunities to rationally manipulate supramolecular chirality and chiral luminescence. Herein, a facile protocol to construct a series of naphthalimide-appended dipeptides is reported that show ultrasound wave-activated supramolecular chirality regulated by odd-even law. Naphthalimide luminophores are conjugated to the dipeptide skeleton with variable alkyl spacers. The presence of tyrosine interferes the kinetic aggregation into achiral nanoparticles without chirality transfer to supramolecular scale. However, ultrasound treatment initiates the nanoparticle-to-helix transition accompanied with the appeared chiral optics, including Cotton effect and circularly polarized luminescence (CPL). The supramolecular chiral parameters, including handedness of helices and chiroptical behaviors, follow the odd-even law of alkyl spacers in dipeptides bearing non-substituted naphthalimides. The amine-substitution boosted the quantum yields of dipeptide whereas no odd-even effect. The two types of dipeptides constituted ideal energy transfer pairs that enable the efficient energy transfer as well as the transportation of odd-even law to dipeptides containing substituted naphthalimides. This work sheds light on the construction of luminescent dipeptides with applications in precise control over chirality transportation and chiral luminescence.

2.
Global Spine J ; : 21925682241283197, 2024 Sep 05.
Article in English | MEDLINE | ID: mdl-39237106

ABSTRACT

STUDY DESIGN: Retrospective Case control Study. OBJECTIVES: To analyze the effect of diffuse idiopathic skeletal hyperostosis (DISH) on the occurrence of new thoracolumbar vertebral fragility fractures (VFFs) at different ages. METHODS: A retrospective analysis of 564 patients, including 189 patients who presented with new-onset thoracolumbar VFFs and 375 patients without spinal fractures, was performed in 4 age groups (50-59 years, 60-69 years, 70-79 years, and 80+ years). DISH was diagnosed based on computed tomography findings, and the Mata score of each disc space level combined with the maximum number of consecutive ossified segments (MNCOS) for each patient was recorded. Data were compared between the fracture and control groups, and odds ratios (ORs) were calculated for each of the 4 age groups using logistic regression. RESULTS: Both the crude ORs and the adjusted ORs of DISH for VFFs decreased with age, with statistical significance shown in the 50-59 years group (crude OR = 4.373, P = 0.017; adjusted OR = 7.111, P = 0.009) and the 80+ years group (crude OR = 0.462, P = 0.018; adjusted OR = 0.495, P = 0.045). The Mata scores and the MNCOS were significant risk factors for VFFs (P < 0.05) in the 50-59 years group, but they were protective factors in the 80+ years group, which was more significant in the T11/12-L5/S1 subsegment. CONCLUSIONS: The effect of DISH on the occurrence of thoracolumbar VFFs is complex, and in patients above 50 years, it changes from a risk factor to a protective factor with increasing age.

3.
Nutrients ; 16(17)2024 Sep 08.
Article in English | MEDLINE | ID: mdl-39275347

ABSTRACT

BACKGROUND/OBJECTIVES: Dietary fats have been linked to the increasing incidence of chronic diseases, including inflammatory bowel diseases (IBD), namely, Crohn's disease (CD). METHODS: This study investigated the impact of pentadecanoic acid (C15:0), a type of an odd-numbered chain saturated fatty acid, for its potential anti-inflammatory properties in different mouse models of experimental IBD using the SAMP1/YitFc (SAMP) mouse line (14- or 24-week-old), including chronic ileitis and DSS-induced colitis. To quantitively assess the effect of C:15, we tested two dosages of C:15 in selected experiments in comparison to control mice. Intestinal inflammation and intestinal permeability were used as primary outcomes. RESULTS: In ileitis, C:15 supplementation showed an anti-inflammatory effect in SAMP mice (e.g., a reduction in ileitis severity vs. control p < 0.0043), which was reproducible when mice were tested in the DSS model of colitis (e.g., reduced permeability vs. control p < 0.0006). Of relevance, even the short-term C:15 therapy prevented colitis in mice by maintaining body weight, decreasing inflammation, preserving gut integrity, and alleviating colitis signs. CONCLUSIONS: Collectively, the findings from both ileitis and colitis in SAMP mice indicate that C:15 may have therapeutic effects in the treatment of IBD (colitis in the short term). This promising effect has major translational potential for the alleviation of IBD in humans.


Subject(s)
Anti-Inflammatory Agents , Dietary Supplements , Disease Models, Animal , Inflammatory Bowel Diseases , Animals , Mice , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/administration & dosage , Inflammatory Bowel Diseases/drug therapy , Male , Permeability , Colitis/chemically induced , Colitis/drug therapy , Colitis/diet therapy , Ileitis/drug therapy , Ileitis/prevention & control
4.
JMIR Pediatr Parent ; 7: e54051, 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39231431

ABSTRACT

BACKGROUND: Web-based self-help (WASH) has been found to be effective in the treatment of child externalizing behavior disorders. However, research on the associations of caregivers' use of WASH and symptom changes of child externalizing behaviors is lacking. OBJECTIVE: This study examined the longitudinal and reciprocal associations between the use of WASH by caregivers of children with externalizing behavior disorders and their children's externalizing behavior symptoms. METHODS: Longitudinal data of 276 families from 2 intervention conditions of a randomized controlled trial (either unguided or supported by a therapist over the phone) were analyzed. Caregiver- and clinician-rated child externalizing behavior symptoms were assessed before (T1), in the middle (T2), and after the 6-month WASH intervention (T3). Additionally, 2 indicators of the caregivers' use of the WASH intervention were considered: number of log-ins (frequency) and the percentage of completed material (intensity). Associations of caregivers' use during early (T1-T2) and late (T2-T3) treatment with child externalizing behavior symptoms were analyzed using path analyses (structural equation modeling). RESULTS: Frequency and intensity of use were higher during the first 3 months than during the next 3 months of the intervention period. The number of log-ins at early treatment was significantly but weakly associated with caregiver-reported child externalizing behavior symptoms in the long term (T3). Moreover, caregiver-reported child externalizing severity at T2 predicted the number of log-ins in the late treatment. The results were not replicated when considering the percentage of completed material as a measure of use or when considering clinician ratings of child externalizing behavior symptoms. CONCLUSIONS: The findings provide the first, albeit weak, evidence for longitudinal associations between caregivers' use of WASH and improvements in caregiver-rated child externalizing behavior symptoms. However, as the associations were rather weak and could not be replicated across different rater perspectives and operationalizations of use, further research is needed to better understand these relations and their interplay with other putative influence factors (eg, quality of the implementation of the interventions, changes in parenting behaviors). TRIAL REGISTRATION: German Clinical Trials Register DRKS00013456; https://www.drks.de/DRKS00013456. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.1186/s12888-020-2481-0.

5.
Behav Res Methods ; 2024 Sep 16.
Article in English | MEDLINE | ID: mdl-39285142

ABSTRACT

Detecting careless responding in survey data is important to ensure the credibility of study findings. Of several available detection methods, personal reliability (PR) is one of the best-performing indices. Curran, Journal of Experimental Social Psychology, 66, 4-19, (2016) proposed a resampled version of personal reliability (RPR). Compared to the conventional PR or even-odd consistency, in which just one set of scale halves is used, RPR is based on repeated calculation of PR across several randomly rearranged sets of scale halves. RPR should therefore be less affected than PR by random errors that may occur when a specific set of scale half pairings is used for the PR calculation. In theory, RPR should outperform PR, but it remains unclear whether it in fact does, and under what conditions the potential gain in detection accuracy is the most pronounced. We conducted two studies: a simulation study examined the performance of the conventional PR and RPR in detecting simulated careless responding, and a real data example study analyzed their performance when detecting human-generated careless responding. In both studies, RPR turned out to be a significantly better careless response indicator than PR. The results also revealed that using 25 resamples for the RPR computation is sufficient to obtain the expected gain in detection accuracy over the conventional PR. We therefore recommend using RPR instead of the conventional PR when screening questionnaire data for careless responding.

6.
J Atten Disord ; 28(12): 1555-1576, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39092505

ABSTRACT

OBJECTIVE: The study aims to examine family functionality, emotion regulation difficulties, preference for loneliness, social exclusion, internalizing and externalizing disorders, and executive functions in children with Attention Deficit Hyperactivity Disorder (ADHD) and Cognitive Disengagement Syndrome (CDS) and compare with ADHD, and ADHD+ Oppositional Defiant Disorder (ODD). METHOD: This study included 842 children aged 8-12 years. The subjects were categorized according to DSM-V as ADHD (n = 246), ADHD + ODD (n = 212), ADHD + CDS (n = 176), and Control group (n = 207). The solitude and social exclusion, difficulties in emotion dysregulation and Barkley SCT scales, Child Behavior Checklist, family assessment device, and Central Vital Signs (CNSVS) test were used. RESULTS: According to the study, children with ADHD + CDS had higher rates of internalizing disorders. They also preferred being alone and experienced more difficulty communicating with their parents and solving problems within the family. Additionally, these children had difficulty recognizing and understanding the emotional reactions of others. The ADHD + ODD group presented a poorer performance on CNSVS domain tests except for the psychomotor speed test than other groups. Also, ADHD + CDS children had the lowest psychomotor speed scores and lower scores on reaction time and cognitive flexibility than pure ADHD children. CONCLUSION: This study will contribute to the etiology, treatment, and clinical discrimination of ADHD + CDS.


Subject(s)
Attention Deficit Disorder with Hyperactivity , Attention Deficit and Disruptive Behavior Disorders , Executive Function , Humans , Child , Attention Deficit Disorder with Hyperactivity/psychology , Attention Deficit Disorder with Hyperactivity/epidemiology , Attention Deficit Disorder with Hyperactivity/diagnosis , Male , Female , Attention Deficit and Disruptive Behavior Disorders/epidemiology , Attention Deficit and Disruptive Behavior Disorders/psychology , Comorbidity , Oppositional Defiant Disorder
7.
Zookeys ; 1209: 1-17, 2024.
Article in English | MEDLINE | ID: mdl-39175834

ABSTRACT

Albinism is an uncommon phenomenon and inherited condition in animals characterized by a partial or complete lack of melanin. The family Xenodermidae Gray, 1849, is a group of caenophidian snakes widely distributed in South, East, and Southeast Asia, including five recognized genera and 36 species. However, there are currently no reports of albinism in any species in Xenodermidae. Achalinussheni Ma, Xu, Qi, Wang, Tang, Huang & Jiang, 2023 was first described based on five male specimens from Loudi City and Nanyue District, Hunan Province, China. At the time, there were no descriptions on female individuals. In this study, we report in detail a collected albinistic specimen of A.sheni, which is the first discovery of wild albinism in the family Xenodermidae. We also provide photographs and descriptions of the first three female specimens of A.sheni and extend the diagnosis of this species.

8.
J Biol Chem ; 300(9): 107662, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39128713

ABSTRACT

Propionic acid links the oxidation of branched-chain amino acids and odd-chain fatty acids to the TCA cycle. Gut microbes ferment complex fiber remnants, generating high concentrations of short chain fatty acids, acetate, propionate and butyrate, which are shared with the host as fuel sources. Analysis of vitamin B12-dependent propionate utilization in skin biopsy samples has been used to characterize and diagnose underlying inborn errors of cobalamin (or B12) metabolism. In these cells, the B12-dependent enzyme, methylmalonyl-CoA mutase (MMUT), plays a central role in funneling propionate to the TCA cycle intermediate, succinate. Our understanding of the fate of propionate in other cell types, specifically, the involvement of the ß-oxidation-like and methylcitrate pathways, is limited. In this study, we have used [14C]-propionate tracing in combination with genetic ablation or inhibition of MMUT, to reveal the differential utilization of the B12-dependent and independent pathways for propionate metabolism in fibroblast versus colon cell lines. We demonstrate that itaconate can be used as a tool to investigate MMUT-dependent propionate metabolism in cultured cell lines. While MMUT gates the entry of propionate carbons into the TCA cycle in fibroblasts, colon-derived cell lines exhibit a quantitatively significant or exclusive reliance on the ß-oxidation-like pathway. Lipidomics and metabolomics analyses reveal that propionate elicits pleiotropic changes, including an increase in odd-chain glycerophospholipids, and perturbations in the purine nucleotide cycle and arginine/nitric oxide metabolism. The metabolic rationale and the regulatory mechanisms underlying the differential reliance on propionate utilization pathways at a cellular, and possibly tissue level, warrant further elucidation.


Subject(s)
Methylmalonyl-CoA Mutase , Propionates , Vitamin B 12 , Humans , Propionates/metabolism , Propionates/pharmacology , Vitamin B 12/metabolism , Methylmalonyl-CoA Mutase/metabolism , Methylmalonyl-CoA Mutase/genetics , Citric Acid Cycle , Fibroblasts/metabolism , Colon/metabolism
9.
Nano Lett ; 24(33): 10040-10046, 2024 Aug 21.
Article in English | MEDLINE | ID: mdl-39133069

ABSTRACT

Quantum interference is a natural consequence of wave-particle duality in quantum mechanics, and is widely observed at the atomic scale. One interesting manifestation of quantum interference is coherent population trapping (CPT), first proposed in three-level driven atomic systems and observed in quantum optical experiments. Here, we demonstrate CPT in a gate-defined semiconductor double quantum dot (DQD), with some unique twists as compared to the atomic systems. Specifically, we observe CPT in both driven and nondriven situations. We further show that CPT in a driven DQD could be used to generate adiabatic state transfer. Moreover, our experiment reveals a nontrivial modulation to the CPT caused by the longitudinal driving field, yielding an odd-even effect and a tunable CPT. Our results broaden the field of CPT, and open up the possibility of quantum simulation and quantum computation based on adiabatic passage in quantum dot systems.

10.
J Hand Surg Glob Online ; 6(4): 488-493, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39166191

ABSTRACT

Purpose: The placement of multistrand sutures during flexor tendon repair is complex and challenging. We developed a new, simpler, nine-strand suture, which we term the Tajima nines. The Tajima nines repair method is a new odd-numbered strand tendon technique. Methods: Fourteen porcine flexor tendons were transected and repaired using the Tajima nines repair method, without placement of peripheral sutures. This technique is a modification of the Lim and Tsai repair method; it uses a 4-0 monofilament nylon, 3-strand line, and two needles. The repaired tendons were tested for linear, noncyclic, load-to-failure tensile strength. The initial gap, 2-mm gap-formation force, and ultimate strength were measured. Results: The initial gap-formation force was 27.9 ± 7.5 newtons (N), the 2-mm gap-formation force was 39.2 ± 4.7 N, and the ultimate strength was 76.7 ± 17.2 N. Eight, three, and three of the 14 tendons repaired using the Tajima nines method demonstrated failure because of thread breakage, knot failure, and suture pull-out, respectively. Conclusions: This biomechanical study demonstrated that Tajima nines repair was associated with particularly high initial tension at the repair site; there were minor variations in the initial load and 2-mm gap-formation load. Our results suggest that Tajima nines repair with peripheral suturing allows the repaired flexor tendon to tolerate the stresses encountered during early active mobilization. Clinical relevance: This simple nine-strand technique will be particularly useful for inexperienced surgeons who perform early active mobilization after primary flexor tendon repair because the technique is a modification of the Lim and Tsai repair method using a triple strand instead of a double strand.

11.
Cureus ; 16(6): e61753, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38975431

ABSTRACT

To the best of the authors' knowledge, this article is the first of its kind in Albania and neighboring countries to investigate the transformative synergistic intervention approach through cognitive behavioral therapy, parent-child interaction therapy (PCIT), and heavy metal detoxification on a child with attention-deficit/hyperactivity disorder (ADHD) and comorbid oppositional defiant disorder (ODD) and dyslexia. The limited mental health awareness in Albania, particularly regarding PCIT and similar treatments, highlights the importance of the applicability and adaptability of such interventions. This study suggests that the rapid management of comorbidities in ADHD, such as ODD and dyslexia, is better achieved by a combined intervention approach and by investigating the biological aspects. Further research with a large sample size is needed to assess the long-term sustainability and scalability of such an approach.

12.
MethodsX ; 12: 102779, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38966718

ABSTRACT

This article describes the ENERGY Pro agent-based model using the Overview, Design Concept, and Details + Human Decision-making (ODD+D protocol). The model is empirically explicit and aims to investigate the adoption decisions of homeowners in Amsterdam on different energy-efficient retrofitting (EER) measures. Following the ODD+D protocol, this study uncovers the conceptual framework used for model construction, the spatial microsimulation process of expanding the data, and the model implementation details. The article also describes sensitivity analysis, validation results, and how to use and adapt the model. With this article, the authors aim to make the model replicable and accessible to other researchers and inspire them using the combination of social simulation and spatial microsimulation in studying the energy transition.•The agent-based model is described using the ODD+D protocol.•The combination of simulation methods is used for constructing an empirical model.•The model on energy transition can be adapted for other cities.

13.
Behav Sci (Basel) ; 14(7)2024 Jul 14.
Article in English | MEDLINE | ID: mdl-39062421

ABSTRACT

Difficulties in emotion regulation (DER) is a defining feature of attention deficit hyperactivity disorder (ADHD), and arguments are being made for it to be considered as a defining feature of oppositional defiant disorder (ODD). However, the consensus is that it is better viewed as an important correlate distinct from ADHD. This study examined the incremental validity of DER over and above trait impulsivity (TI) in the predictions of ADHD and ODD symptoms. It also examined the incremental validity of affect lability (AL) over and above TI and (DER) in these predictions. Five hundred and twenty-five adults from the general community completed a series of questionnaires. A model-based SEM approach for evaluating incremental validity indicated that TI predicted ADHD and ODD symptoms over age; DER predicted ADHD and ODD symptoms over age and TI; and AL did not predict ADHD and ODD symptoms over and above age, IT, or DER. In addition, AL predicted ADHD and ODD symptoms over age and TI, and DER also predicted ADHD and ODD symptoms over and above age, TI, and AL. In conclusion, TI is core to ADHD, and although DER is important, it is unlikely to be relevant as a diagnostic indicator for ADHD or ODD. These findings notwithstanding, there is need for caution when interpreting our findings, as the study did not control for potentially influencing factors on emotional regulation such as age, gender, culture, and existing psychopathologies.

14.
ACS Appl Mater Interfaces ; 16(31): 41371-41378, 2024 Aug 07.
Article in English | MEDLINE | ID: mdl-39046888

ABSTRACT

The emergence of an intrinsic quantum anomalous Hall (QAH) insulator with long-range magnetic order triggers unprecedented prosperity for combining topology and magnetism in low dimensions. Here, based on stacked two-dimensional LiFeTe, we confirm that magnetic coupling and topological electronic states can be simultaneously manipulated by just changing the layer numbers. Monolayer LiFeTe shows intralayer ferrimagnetic coupling, behaving as a QAH insulator with Chern number C = 2. Beyond the monolayer, the odd and even layers of LiFeTe correspond to uncompensated and compensated interlayer antiferromagnets, resulting in unexpected QAH and quantum spin Hall (QSH) states, respectively. Moreover, the spin Chern number is proportional to the stacking layer numbers in even-layer LiFeTe, proving that the spin Hall conductivity can be continuously enhanced by increasing layer numbers. Therefore, the odd-even-layer-dependent QAH and QSH effects found in LiFeTe topological insulators offer new insight into regulating quantum states in two-dimensional topological materials.

15.
J Appl Stat ; 51(9): 1642-1663, 2024.
Article in English | MEDLINE | ID: mdl-38933143

ABSTRACT

The article proposes a new regression based on the generalized odd log-logistic family for interval-censored data. The survival times are not observed for this type of data, and the event of interest occurs at some random interval. This family can be used in interval modeling since it generalizes some popular lifetime distributions in addition to its ability to present various forms of the risk function. The estimation of the parameters is addressed by the classical and Bayesian methods. We examine the behavior of the estimates for some sample sizes and censorship percentages. Selection criteria, likelihood ratio tests, residual analysis, and graphical techniques assess the goodness of fit of the fitted models. The usefulness of the proposed models is red shown by means of two real data sets.

16.
Entropy (Basel) ; 26(6)2024 May 31.
Article in English | MEDLINE | ID: mdl-38920494

ABSTRACT

We derive the probability representation of even and odd cat states of two and three qubits. These states are even and odd superpositions of spin-1/2 eigenstates corresponding to two opposite directions along the z axis. The probability representation of even and odd cat states of an oscillating spin-1/2 particle is also discussed. The exact formulas for entangled probability distributions describing density matrices of all these states are obtained.

17.
J Nat Med ; 78(4): 901-907, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38780746

ABSTRACT

Daphnane diterpenoids were recognized for their extensive range of potent biological activities. In the present study, phytochemical investigation including LC-MS/MS analysis resulted in the identification of five daphnane diterpenoid orthoesters (1-5). Among the five daphnane diterpenoids, two previously unreported compounds, daphnepedunins I and J (2 and 4) were isolated from Daphne pedunculata. The structure of new compounds was elucidated with extensive physicochemical and spectroscopic analyses. Their structure was characterized by the presence of an unusual odd-numbered aliphatic chain connected to an orthoester. The isolated compounds were evaluated for their anti-HIV activity against HIV-1 infection of MT4 cells, and the results indicated that compound 1 showed the most potent anti-HIV activity with an IC50 value of 0.82 nM.


Subject(s)
Anti-HIV Agents , Daphne , Diterpenes , Diterpenes/chemistry , Diterpenes/isolation & purification , Diterpenes/pharmacology , Daphne/chemistry , Anti-HIV Agents/chemistry , Anti-HIV Agents/pharmacology , Anti-HIV Agents/isolation & purification , Molecular Structure , HIV-1/drug effects , Humans , Tandem Mass Spectrometry , Cell Line , Esters/chemistry , Plant Extracts/chemistry , Plant Extracts/pharmacology
18.
Article in English | MEDLINE | ID: mdl-38802092

ABSTRACT

Female youth with oppositional defiant disorder (ODD) and conduct disorder (CD) are an under studied and underserved population at high risk for poor adjustment in later life. Stadler et al. (2024) attempt to redress this situation for adolescent females with CD or ODD with an adapted version of the skills training program START NOW. They describe the results of an ambitious randomized control trial, comparing START NOW with standard care in youth welfare settings in Germany, Switzerland, and The Netherlands. The findings appear promising, but the paper is especially valuable for the spotlight it shines on the needs of this underserved population and those caring for them, together with the importance of undertaking such trials despite their challenges. This commentary seeks to encourage readers to engage with the START NOW trial.

19.
Food Sci Biotechnol ; 33(8): 1947-1956, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38752121

ABSTRACT

Heptadecanoic acid (C17:0), an odd-chain saturated fatty acid (OCSFA) in ruminant lipid, has been demonstrated to be potential for treating cancers. Our results also showed that sheep tail fat (STF) with higher level of C17:0-containing saturated fatty acids (SFAs) whereas lower level of oleic acid (C18:1), performed remarkable inhibition against non-small-cell lung cancer (NSCLC) cells. To enrich the content of C17:0, a C17:0-rich SFA concentrate (HRSC) was prepared from STF by solvent crystallization and urea complexation methods (hexane/STF = 3.5/1, 4 °C for 8 h, and 80% ethanol/urea/free fatty acids = 8/1/1, 4 °C for 6 h). The content of C17:0 was up from 3.02 to 6.34% and the recovery was 4.17%. Biological experiments showed that HRSC exerted better antiproliferative effect against NSCLC cells. Moreover, HRSC performed enhanced inhibitory effect in A549 cell xenograft mouse model. Therefore, HRSC has the potential to be applied in adjuvant therapy for NSCLC. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01504-w.

20.
Proc Natl Acad Sci U S A ; 121(19): e2219385121, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38701120

ABSTRACT

Odd viscosity couples stress to strain rate in a dissipationless way. It has been studied in plasmas under magnetic fields, superfluid [Formula: see text], quantum-Hall fluids, and recently in the context of chiral active matter. In most of these studies, odd terms in the viscosity obey Onsager reciprocal relations. Although this is expected in equilibrium systems, it is not obvious that Onsager relations hold in active materials. By directly coarse-graining the kinetic energy and independently using both the Poisson-bracket formalism and a kinetic theory derivation, we find that the appearance of a nonvanishing angular momentum density, which is a hallmark of chiral active materials, necessarily breaks Onsager reciprocal relations. This leads to a non-Hermitian dynamical matrix for the total hydrodynamic momentum and to the appearance of odd viscosity and other nondissipative contributions to the viscosity. Furthermore, by accounting for both the angular momentum density and interactions that lead to odd viscosity, we find regions in the parameter space in which 3D odd mechanical waves propagate and regions in which they are mechanically unstable. The lines separating these regions are continuous lines of exceptional points, suggesting a possible nonreciprocal phase transition.

SELECTION OF CITATIONS
SEARCH DETAIL