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1.
Mol Ecol ; 33(14): e17440, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38946459

RESUMEN

We present palaeogenomes of three morphologically unidentified Anatolian equids dating to the first millennium BCE, sequenced to a coverage of 0.6-6.4×. Mitochondrial DNA haplotypes of the Anatolian individuals clustered with those of Equus hydruntinus (or Equus hemionus hydruntinus), the extinct European wild ass, secular name 'hydruntine'. Further, the Anatolian wild ass whole genome profiles fell outside the genomic diversity of other extant and past Asiatic wild ass (E. hemionus) lineages. These observations suggest that the three Anatolian wild asses represent hydruntines, making them the latest recorded survivors of this lineage, about a millennium later than the latest observations in the zooarchaeological record. Our mitogenomic and genomic analyses indicate that E. h. hydruntinus was a clade belonging to ancient and present-day E. hemionus lineages that radiated possibly between 0.6 and 0.8 Mya. We also find evidence consistent with recent gene flow between hydruntines and Middle Eastern wild asses. Analyses of genome-wide heterozygosity and runs of homozygosity suggest that the Anatolian wild ass population may have lost genetic diversity by the mid-first millennium BCE, a possible sign of its eventual demise.


Asunto(s)
ADN Mitocondrial , Flujo Génico , Haplotipos , Filogenia , Animales , ADN Mitocondrial/genética , Haplotipos/genética , Equidae/genética , Genoma Mitocondrial , Extinción Biológica , Fósiles , Genética de Población , Variación Genética
2.
Physiol Rep ; 12(13): e16130, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38946069

RESUMEN

The aim of this study was to identify risk factors for abdominal aortic aneurysm (AAA) from the largest Welsh screening cohort to date. Patients were recruited from 1993 (to 2015) as part of the South East Wales AAA screening programme through general practitioners. Demographic data and risk factors were collected by means of a self-report questionnaire. Statistical tests were performed to determine whether associations could be observed between AAA and potential risk factors. Odds ratios (OR) were also calculated for each of the risk factors identified. A total of 6879 patients were included in the study. Two hundred and seventy-five patients (4.0%) presented with AAA, of which 16% were female and 84% were male. Patients with AAA were older than the (no AAA) control group (p < 0.0001). The following risk factors were identified for AAA: family history of AAA (p < 0.0001); history of vascular surgery (p < 0.0001), cerebrovascular accident (p < 0.0001), coronary heart disease (p < 0.0001), diabetes (p < 0.0001), medication (p = 0.0018), claudication (p < 0.0001), smoking history (p = 0.0001) and chronic obstructive pulmonary disorder (p = 0.0007). AAA is associated with classical vascular risk factors, in addition to other less-well-documented risk factors including previous vascular surgery. These findings have practical implications with the potential to improve future clinical screening of patients in order to reduce AAA mortality.


Asunto(s)
Aneurisma de la Aorta Abdominal , Humanos , Aneurisma de la Aorta Abdominal/epidemiología , Masculino , Femenino , Anciano , Factores de Riesgo , Persona de Mediana Edad , Estudios Prospectivos , Estudios Longitudinales , Anciano de 80 o más Años , Gales/epidemiología
3.
Acta Physiol (Oxf) ; : e14197, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38958262

RESUMEN

AIM: How the cerebral metabolic rates of oxygen and glucose utilization (CMRO2 and CMRGlc, respectively) are affected by alterations in arterial PCO2 (PaCO2) is equivocal and therefore was the primary question of this study. METHODS: This retrospective analysis involved pooled data from four separate studies, involving 41 healthy adults (35 males/6 females). Participants completed stepwise steady-state alterations in PaCO2 ranging between 30 and 60 mmHg. The CMRO2 and CMRGlc were assessed via the Fick approach (CBF × arterial-internal jugular venous difference of oxygen or glucose content, respectively) utilizing duplex ultrasound of the internal carotid artery and vertebral artery to calculate cerebral blood flow (CBF). RESULTS: The CMRO2 was altered by 0.5 mL × min-1 (95% CI: -0.6 to -0.3) per mmHg change in PaCO2 (p < 0.001) which corresponded to a 9.8% (95% CI: -13.2 to -6.5) change in CMRO2 with a 9 mmHg change in PaCO2 (inclusive of hypo- and hypercapnia). The CMRGlc was reduced by 7.7% (95% CI: -15.4 to -0.08, p = 0.045; i.e., reduction in net glucose uptake) and the oxidative glucose index (ratio of oxygen to glucose uptake) was reduced by 5.6% (95% CI: -11.2 to 0.06, p = 0.049) with a + 9 mmHg increase in PaCO2. CONCLUSION: Collectively, the CMRO2 is altered by approximately 1% per mmHg change in PaCO2. Further, glucose is incompletely oxidized during hypercapnia, indicating reductions in CMRO2 are either met by compensatory increases in nonoxidative glucose metabolism or explained by a reduction in total energy production.

4.
Biotechnol Bioeng ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38951956

RESUMEN

In recent decades, biocatalysis has emerged as an important alternative to chemical catalysis in pharmaceutical manufacturing. Biocatalysis is attractive because enzymatic cascades can synthesize complex molecules with incredible selectivity, yield, and in an environmentally benign manner. Enzymes for pharmaceutical biocatalysis are typically used in their unpurified state, since it is time-consuming and cost-prohibitive to purify enzymes using conventional chromatographic processes at scale. However, impurities present in crude enzyme preparations can consume substrate, generate unwanted byproducts, as well as make the isolation of desired products more cumbersome. Hence, a facile, nonchromatographic purification method would greatly benefit pharmaceutical biocatalysis. To address this issue, here we have captured enzymes into membraneless compartments by fusing enzymes with an intrinsically disordered protein region, the RGG domain from LAF-1. The RGG domain can undergo liquid-liquid phase separation, forming liquid condensates triggered by changes in temperature or salt concentration. By centrifuging these liquid condensates, we have successfully purified enzyme-RGG fusions, resulting in significantly enhanced purity compared to cell lysate. Furthermore, we performed enzymatic reactions utilizing purified fusion proteins to assay enzyme activity. Results from the enzyme assays indicate that enzyme-RGG fusions purified by the centrifugation method retain enzymatic activity, with greatly reduced background activity compared to crude enzyme preparations. Our work focused on three different enzymes-a kinase, a phosphorylase, and an ATP-dependent ligase. The kinase and phosphorylase are components of the biocatalytic cascade for manufacturing molnupiravir, and we demonstrated facile co-purification of these two enzymes by co-phase separation. To conclude, enzyme capture by RGG tagging promises to overcome difficulties in bioseparations and biocatalysis for pharmaceutical synthesis.

7.
Am J Geriatr Psychiatry ; 1: 7-16, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38993691

RESUMEN

Introduction: This study investigated a remotely delivered, therapist-facilitated, personalized music listening intervention for community-dwelling older adults experiencing loneliness during the Covid-19 pandemic. We assessed its feasibility and individuals' experiences of social connection and emotional well-being during the intervention. Methods: Ten cognitively unimpaired older adults who endorsed loneliness completed eight weekly sessions with a board-certified music therapist via Zoom. Participants were guided in developing two online personalized music playlists and were asked to listen to playlists for at least one hour daily. Feasibility metrics were attendance, accessibility, and compliance rates. Post-study interview responses were analyzed using a rapid qualitative methodology. Exploratory pre- and post-study measures of loneliness and other aspects of psychological well-being were obtained using validated questionnaires. Results: Ten participants (mean age 75.38 [65 to 85] years, 80% women) were enrolled from March to August 2021. Attendance and compliance rates were 100% and the accessibility rate was 90%. Most participants associated music with positive memories before the program and many reported that the intervention prompted them to reconnect with music or listen to music with greater intention. They cited increased connection from interacting with the music therapist and the music itself, as well as specific positive emotional impacts from integrating music into their daily lives. Median pre- to post-questionnaire measures of psychological function all changed in an improved direction. Discussion: Remotely delivered music therapy may be a promising intervention to promote regular music listening and socioemotional well-being in lonely older adults.


Asunto(s)
COVID-19 , Soledad , Musicoterapia , Humanos , Musicoterapia/métodos , Anciano , Femenino , Masculino , COVID-19/psicología , Soledad/psicología , Proyectos Piloto , Anciano de 80 o más Años , Estudios de Factibilidad , SARS-CoV-2
8.
Nat Microbiol ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38977907

RESUMEN

Examining host-pathogen interactions in animals can capture aspects of infection that are obscured in cell culture. Using CRISPR-based screens, we functionally profile the entire genome of the apicomplexan parasite Toxoplasma gondii during murine infection. Barcoded gRNAs enabled bottleneck detection and mapping of population structures within parasite lineages. Over 300 genes with previously unknown roles in infection were found to modulate parasite fitness in mice. Candidates span multiple axes of host-parasite interaction. Rhoptry Apical Surface Protein 1 was characterized as a mediator of host-cell tropism that facilitates repeated invasion attempts. GTP cyclohydrolase I was also required for fitness in mice and druggable through a repurposed compound, 2,4-diamino-6-hydroxypyrimidine. This compound synergized with pyrimethamine against T. gondii and malaria-causing Plasmodium falciparum parasites. This work represents a complete survey of an apicomplexan genome during infection of an animal host and points to novel interfaces of host-parasite interaction.

9.
Nat Commun ; 15(1): 6172, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39039092

RESUMEN

The severity of bacterial pneumonia can be worsened by impaired innate immunity resulting in ineffective pathogen clearance. We describe a mitochondrial protein, aspartyl-tRNA synthetase (DARS2), which is released in circulation during bacterial pneumonia in humans and displays intrinsic innate immune properties and cellular repair properties. DARS2 interacts with a bacterial-induced ubiquitin E3 ligase subunit, FBXO24, which targets the synthetase for ubiquitylation and degradation, a process that is inhibited by DARS2 acetylation. During experimental pneumonia, Fbxo24 knockout mice exhibit elevated DARS2 levels with an increase in pulmonary cellular and cytokine levels. In silico modeling identified an FBXO24 inhibitory compound with immunostimulatory properties which extended DARS2 lifespan in cells. Here, we show a unique biological role for an extracellular, mitochondrially derived enzyme and its molecular control by the ubiquitin apparatus, which may serve as a mechanistic platform to enhance protective host immunity through small molecule discovery.


Asunto(s)
Aspartato-ARNt Ligasa , Inmunidad Innata , Ratones Noqueados , Mitocondrias , Ubiquitinación , Animales , Aspartato-ARNt Ligasa/metabolismo , Aspartato-ARNt Ligasa/genética , Humanos , Ratones , Mitocondrias/metabolismo , Proteínas F-Box/metabolismo , Proteínas F-Box/genética , Ratones Endogámicos C57BL , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Proteolisis , Femenino , Masculino , Citocinas/metabolismo , Células HEK293 , Acetilación , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética
10.
Org Lett ; 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39038111

RESUMEN

We have developed a diastereoselective synthesis of 43 novel 7-azanorbornanes using tertiary amine N-oxides and substituted alkenes. Our method uses an efficient [3 + 2] cycloaddition, starting from either commercially available or easily accessible precursors to generate yields up to 97% and diastereomeric ratios up to >20:1. Density functional theory (DFT) calculations were performed, suggesting that the observed diastereoselectivity is likely due to steric considerations.

11.
Nanomaterials (Basel) ; 14(12)2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38921908

RESUMEN

Anionic carboxylated cellulose nanofibers (CNF) are effective media to remove cationic contaminants from water. In this study, sustainable cationic CNF-based adsorbents capable of removing anionic contaminants were demonstrated using a simple approach. Specifically, the zero-waste nitro-oxidization process was used to produce carboxylated CNF (NOCNF), which was subsequently converted into a cationic scaffold by crosslinking with aluminum ions. The system, termed Al-CNF, is found to be effective for the removal of fluoride ions from water. Using the Langmuir isotherm model, the fluoride adsorption study indicates that Al-CNF has a maximum adsorption capacity of 43.3 mg/g, which is significantly higher than that of alumina-based adsorbents such as activated alumina (16.3 mg/g). The selectivity of fluoride adsorption in the presence of other anionic species (nitrate or sulfate) by Al-CNF at different pH values was also evaluated. The results indicate that Al-CNF can maintain a relatively high selectivity towards the adsorption of fluoride. Finally, the sequential applicability of using spent Al-CNF after the fluoride adsorption to further remove cationic contaminant such as Basic Red 2 dye was demonstrated. The low cost and relatively high adsorption capacity of Al-CNF make it suitable for practical applications in fluoride removal from water.

12.
Nano Lett ; 24(26): 8030-8037, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38912680

RESUMEN

Dielectric screening plays a vital role in determining physical properties at the nanoscale and affects our ability to detect and characterize nanomaterials using optical techniques. We study how dielectric screening changes electromagnetic fields and many-body effects in nanostructures encapsulated inside carbon nanotubes. First, we show that metallic outer walls reduce the scattering intensity of the inner tube by 2 orders of magnitude compared to that of air-suspended inner tubes, in line with our local field calculations. Second, we find that the dielectric shift of the optical transition energies in the inner walls is greater when the outer tube is metallic than when it is semiconducting. The magnitude of the shift suggests that the excitons in small-diameter inner metallic tubes are thermally dissociated at room temperature if the outer tube is also metallic, and in essence, we observe band-to-band transitions in thin metallic double-walled nanotubes.

14.
Artículo en Inglés | MEDLINE | ID: mdl-38942226

RESUMEN

BACKGROUND: Over-prescription of opioids in the United States increases risks of opioid dependence, overdose, and death. Increased perioperative and postoperative opioid use during orthopedic shoulder surgery is a significant risk factor for long term opioid dependence. The authors hypothesized that a multidisciplinary perioperative pain management program (Transitional Pain Service or TPS) for major shoulder surgery would lead to a reduced amount of opioids required postoperatively. METHODS: A TPS was implemented at a Veterans Affairs Medical Center focused on non-opioid pain management and cessation support. Opioid consumption during the implementation of the TPS was compared to a historical cohort. All patients undergoing shoulder arthroplasty or rotator cuff repair were included. The primary outcome was the proportion of patients continuing opioid use at 90 days postoperatively. Secondary outcomes included postoperative pain scores, time to opioid cessation, and median opioid tablets consumed at 90-days. A multivariable model was developed to predict total opioid use at 90-days postoperatively. Kaplan Meier curves were calculated for time to opioid cessation. RESULTS: The TPS group demonstrated decreased persistent opioid use at 90 days post-discharge (12.6% vs. 28.6%; p=0.018). Independent predictors associated with increased total opioid tablet prescriptions at 90 days included length of stay (ß=19.17), anxiety diagnosis (ß=37.627), and number of tablets prescribed at discharge (ß=1.353). Shoulder arthroplasty surgery (TSA) was associated with decreased 90-day opioid utilization (ß= -32.535) when compared to cuff repair (RCR). Median time to cessation was shorter in TSA (6 days) when compared with RCR (8 days). Pain scores were reduced compared to population mean by post-discharge day 2 for TSA and by post-discharge day 7 for RCR. Median number of post-discharge opioid tablets (oxycodone 5 mg) consumed under TPS management was 25 in both RCR and TSA surgery groups (180 MME). DISCUSSION AND CONCLUSIONS: This study demonstrates that a TPS reduces the amount of opioid use of patients undergoing shoulder arthroplasty or cuff repair at 90 days when compared with a historical control. Multivariable regression indicated that fewer opioid tablets at discharge was a modifiable factor that may aid in reducing opioid consumption and that anxiety diagnosis, increased length of stay, and cuff repair surgery were other factors independently associated with increased opioid consumption. This data will assist surgeons in counseling patients, setting narcotic use expectations, and minimizing overprescribing. Use of a similar multidisciplinary perioperative pain management program may greatly reduce opioid over prescriptions nationally.

15.
Prog Cardiovasc Dis ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38936757

RESUMEN

Artificial intelligence (AI) is an emerging technology with numerous healthcare applications. AI could prove particularly useful in the cardiac intensive care unit (CICU) where its capacity to analyze large datasets in real-time would assist clinicians in making more informed decisions. This systematic review aimed to explore current research on AI as it pertains to the CICU. A PRISMA search strategy was carried out to identify the pertinent literature on topics including vascular access, heart failure care, circulatory support, cardiogenic shock, ultrasound, and mechanical ventilation. Thirty-eight studies were included. Although AI is still in its early stages of development, this review illustrates its potential to yield numerous benefits in the CICU.

16.
J Control Release ; 372: 674-681, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38909700

RESUMEN

One of the primary obstacles in treating central nervous system (CNS) disorders lies in the limited ability of disease-modifying drugs to cross the blood-brain barrier (BBB). Our previously described Minimally Invasive Nasal Depot (MIND) technique has proven successful in delivering various drugs to the brain in rat models via a trans-olfactory mucosal approach. In this study, we introduce a novel Minimally Invasive Nasal Infusion (MINI) delivery approach for administering ovalbumin, a model protein, utilizing a programmable infusion pump (iPRECIO SMP-310R) in a mouse model. This research highlights the significant role of olfactory mucosa in nose-to-brain delivery, with an efficacy of nearly 45% compared to intracerebroventricular (ICV) administration. This demonstrates its potential as an alternative procedure for treating CNS diseases, offering a greater safety profile relative to the highly invasive clinical routes traditionally adopted for CNS drug delivery.

17.
Clin Neurol Neurosurg ; 243: 108383, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38924843

RESUMEN

Giant ruptured distal anterior cerebral artery aneurysms are rare, challenging pathologies that may require a combination of microsurgical and endovascular techniques for optimal treatment [1-9]. We describe the case of a female in her 40 s who presented with a Hunt-Hess 4, Fisher 4 subarachnoid hemorrhage from a multiply ruptured, giant distal anterior cerebral artery aneurysm. The patient underwent coil and n-BCA glue embolization of the aneurysm and its feeding A2 anterior cerebral artery. She subsequently underwent decompressive craniectomy, intracerebral hematoma evacuation, and microsurgical trapping and resection of the aneurysm. Postoperative imaging demonstrated no further aneurysm filling, complete hematoma evacuation, and good decompression. The technical considerations and literature for the combined treatment of large and giant ruptured aneurysms are reviewed. The case presentation, operative nuances, and postoperative course with imaging are reviewed with detailed anatomical diagrams to orient the viewer. The patient consented to the procedure and to the publication of her imaging.


Asunto(s)
Aneurisma Roto , Craniectomía Descompresiva , Embolización Terapéutica , Aneurisma Intracraneal , Humanos , Femenino , Craniectomía Descompresiva/métodos , Aneurisma Intracraneal/cirugía , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Roto/cirugía , Aneurisma Roto/diagnóstico por imagen , Embolización Terapéutica/métodos , Adulto , Hemorragia Subaracnoidea/cirugía , Hemorragia Subaracnoidea/diagnóstico por imagen , Microcirugia/métodos , Procedimientos Endovasculares/métodos , Arteria Cerebral Anterior/cirugía , Arteria Cerebral Anterior/diagnóstico por imagen
18.
Cell ; 187(14): 3726-3740.e43, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38861993

RESUMEN

Many growth factors and cytokines signal by binding to the extracellular domains of their receptors and driving association and transphosphorylation of the receptor intracellular tyrosine kinase domains, initiating downstream signaling cascades. To enable systematic exploration of how receptor valency and geometry affect signaling outcomes, we designed cyclic homo-oligomers with up to 8 subunits using repeat protein building blocks that can be modularly extended. By incorporating a de novo-designed fibroblast growth factor receptor (FGFR)-binding module into these scaffolds, we generated a series of synthetic signaling ligands that exhibit potent valency- and geometry-dependent Ca2+ release and mitogen-activated protein kinase (MAPK) pathway activation. The high specificity of the designed agonists reveals distinct roles for two FGFR splice variants in driving arterial endothelium and perivascular cell fates during early vascular development. Our designed modular assemblies should be broadly useful for unraveling the complexities of signaling in key developmental transitions and for developing future therapeutic applications.


Asunto(s)
Diferenciación Celular , Factores de Crecimiento de Fibroblastos , Receptores de Factores de Crecimiento de Fibroblastos , Transducción de Señal , Animales , Humanos , Receptores de Factores de Crecimiento de Fibroblastos/metabolismo , Factores de Crecimiento de Fibroblastos/metabolismo , Ratones , Ligandos , Calcio/metabolismo , Sistema de Señalización de MAP Quinasas
19.
ALTEX ; 41(3): 402-424, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38898799

RESUMEN

The webinar series and workshop titled "Trust Your Gut: Establishing Confidence in Gastrointestinal Models ­ An Overview of the State of the Science and Contexts of Use" was co-organized by NICEATM, NIEHS, FDA, EPA, CPSC, DoD, and the Johns Hopkins Center for Alternatives to Animal Testing (CAAT) and hosted at the National Institutes of Health in Bethesda, MD, USA on October 11-12, 2023. New approach methods (NAMs) for assessing issues of gastrointestinal tract (GIT)- related toxicity offer promise in addressing some of the limitations associated with animal-based assessments. GIT NAMs vary in complexity, from two-dimensional monolayer cell line-based systems to sophisticated 3-dimensional organoid systems derived from human primary cells. Despite advances in GIT NAMs, challenges remain in fully replicating the complex interactions and pro­cesses occurring within the human GIT. Presentations and discussions addressed regulatory needs, challenges, and innovations in incorporating NAMs into risk assessment frameworks; explored the state of the science in using NAMs for evaluating systemic toxicity, understanding absorption and pharmacokinetics, evaluating GIT toxicity, and assessing potential allergenicity; and discussed strengths, limitations, and data gaps of GIT NAMs as well as steps needed to establish confidence in these models for use in the regulatory setting.


Non-animal methods to assess whether chemicals may be toxic to the human digestive tract promise to complement or improve on animal-based methods. These approaches, which are based on human or animal cells and/or computer models, are faced with their own technical challenges and need to be shown to predict adverse effects in humans. Regulators are tasked with evaluating submitted data to best protect human health and the environment. A webinar series and workshop brought together scientists from academia, industry, military, and regulatory authorities from dif­ferent countries to discuss how non-animal methods can be integrated into the risk assessment of drugs, food additives, dietary supplements, pesticides, and industrial chemicals for gastrointestinal toxicity.


Asunto(s)
Alternativas a las Pruebas en Animales , Tracto Gastrointestinal , Humanos , Alternativas a las Pruebas en Animales/métodos , Animales , Modelos Biológicos , Medición de Riesgo/métodos , Pruebas de Toxicidad/métodos
20.
Langmuir ; 40(25): 13319-13329, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38859701

RESUMEN

Flow-assisted alignment of anisotropic nanoparticles is a promising route for the bottom-up assembly of advanced materials with tunable properties. While aligning processes could be optimized by controlling factors such as solvent viscosity, flow deformation, and the structure of the particles themselves, it is necessary to understand the relationship between these factors and their effect on the final orientation. In this study, we investigated the flow of surface-charged cellulose nanocrystals (CNCs) with the shape of a rigid rod dispersed in water and propylene glycol (PG) in an isotropic tactoid state. In situ scanning small-angle X-ray scattering (SAXS) and rheo-optical flow-stop experiments were used to quantify the dynamics, orientation, and structure of the assigned system at the nanometer scale. The effects of both shear and extensional flow fields were revealed in a single experiment by using a flow-focusing channel geometry, which was used as a model flow for nanomaterial assembly. Due to the higher solvent viscosity, CNCs in PG showed much slower Brownian dynamics than CNCs in water and thus could be aligned at lower deformation rates. Moreover, CNCs in PG also formed a characteristic tactoid structure but with less ordering than CNCs in water owing to weaker electrostatic interactions. The results indicate that CNCs in water stay assembled in the mesoscale structure at moderate deformation rates but are broken up at higher flow rates, enhancing rotary diffusion and leading to lower overall alignment. Albeit being a study of cellulose nanoparticles, the fundamental interplay between imposed flow fields, Brownian motion, and electrostatic interactions likely apply to many other anisotropic colloidal systems.

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