Active fluids such as swarming bacteria and motile colloids exhibit exotic properties different from conventional equilibrium materials. As a peculiar example, a spherical tracer immersed inside ...active fluids shows an enhanced translational diffusion, orders of magnitude stronger than its intrinsic Brownian motion. Here, rather than spherical tracers, we investigate the diffusion of isolated ellipsoids in a quasi-two-dimensional bacterial bath. Our study shows a nonlinear enhancement of both translational and rotational diffusions of ellipsoids. More importantly, we uncover an anomalous coupling between particles' translation and rotation that is strictly prohibited in Brownian diffusion. The coupling reveals a counterintuitive anisotropic particle diffusion, where an ellipsoid diffuses fastest along its minor axis in its body frame. Combining experiments with theoretical modeling, we show that such an anomalous diffusive behavior arises from the generic straining flow of swimming bacteria. Our work illustrates an unexpected feature of active fluids and deepens our understanding of transport processes in microbiological systems.
Emerging evidence suggests that gut microbiome composition alterations affect neurodegeneration through neuroinflammation in the pathogenesis of Parkinson's disease (PD). Here, we evaluate gut ...microbiota alterations and host cytokine responses in a population of Taiwanese patients with PD.
Fecal microbiota communities from 80 patients with PD and 77 age and gender-matched controls were assessed by sequencing the V3-V4 region of the 16S ribosomal RNA gene. Diet and comorbidities were controlled in the analyses. Plasma concentrations of IL-1β, IL-2, IL-4, IL-6, IL-13, IL-18, GM-CSF, IFNγ, and TNFα were measured by a multiplex immunoassay and relationships between microbiota, clinical characteristics, and cytokine levels were analyzed in the PD group. We further examined the cytokine changes associated with the altered gut microbiota seen in patients with PD in another independent cohort of 120 PD patients and 120 controls.
Microbiota from patients with PD was altered relative to controls and dominated by Verrucomicrobia, Mucispirillum, Porphyromonas, Lactobacillus, and Parabacteroides. In contrast, Prevotella was more abundant in controls. The abundances of Bacteroides were more increased in patients with non-tremor PD subtype than patients with tremor subtype. Bacteroides abundance was correlated with motor symptom severity defined by UPDRS part III motor scores (rho = 0.637 95% confidence interval 0.474 to 0.758, P < 0.01). Altered microbiota was correlated with plasma concentrations of IFNγ and TNFα. There was a correlation between Bacteroides and plasma level of TNFα (rho = 0.638 95% CI: 0.102-0.887, P = 0.02); and a correlation between Verrucomicrobia abundance and plasma concentrations of IFNγ (rho = 0.545 95% CI - 0.043-0.852, P = 0.05). The elevated plasma cytokine responses were confirmed in an additional independent 120 patients with PD and 120 controls (TNFα: PD vs. control 8.51 ± 4.63 pg/ml vs. 4.82 ± 2.23 pg/ml, P < 0.01; and IFNγ: PD vs. control: 38.45 ± 7.12 pg/ml vs. 32.79 ± 8.03 pg/ml, P = 0.03).
This study reveals altered gut microbiota in PD and its correlation with clinical phenotypes and severity in our population. The altered plasma cytokine profiles associated with gut microbiome composition alterations suggest aberrant immune responses may contribute to inflammatory processes in PD.
Pulmonary inflammation, which is characterized by the presence of perivascular macrophages, has been proposed as a key pathogenic driver of pulmonary hypertension (PH), a vascular disease with ...increasing global significance. However, the mechanisms of expansion of lung macrophages and the role of blood-borne monocytes in PH are poorly understood. Using multicolor flow cytometric analysis of blood in mouse and rat models of PH and patients with PH, an increase in blood monocytes was observed. In parallel, lung tissue displayed increased chemokine transcript expression, including those responsible for monocyte recruitment, such as
and
, accompanied by an expansion of interstitial lung macrophages. These data indicate that blood monocytes are recruited to lung perivascular spaces and differentiate into inflammatory macrophages. Correspondingly, parabiosis between congenically different hypoxic mice demonstrated that most interstitial macrophages originated from blood monocytes. To define the actions of these cells in PH in vivo, we reduced blood monocyte numbers via genetic deficiency of
or
in chronically hypoxic male mice and by pharmacologic inhibition of Cx
cl1 in monocrotaline-exposed rats. Both models exhibited decreased inflammatory blood monocytes, as well as interstitial macrophages, leading to a substantial decrease in arteriolar remodeling but with a less robust hemodynamic effect. This study defines a direct mechanism by which interstitial macrophages expand in PH. It also demonstrates a pathway for pulmonary vascular remodeling in PH that depends upon interstitial macrophage-dependent inflammation yet is dissociated, at least in part, from hemodynamic consequences, thus offering guidance on future anti-inflammatory therapeutic strategies in this disease.
This study developed a model that examined the relationship between undergraduate students' beliefs, norms and pro-environment behavioral intentions in the context of global climate change (GCC). The ...model was further evaluated to determine whether latent variables, such as sustainability value, environmental concern, social norms, perceived risk, pro-environmental attitude, as defined by the theory of planned behavior and value-belief-norm theory, significantly influenced students' intentions towards pro-environmental behavior. The research model was empirically tested using data collected form 275 undergraduate students. Empirical results found support for four interaction effects of personality traits and the related latent variables of environmental attitude, including sustainability value, social norms, environmental concern and perceived risk. The impact of undergraduate students' environmental attitudes was moderated by personality traits. The findings of this research offer policy makers and enterprises better understandings of undergraduate students' attitudes and behavioral intentions towards GCC and promote the visibility of this issue.
Proteins immobilized in metal–organic frameworks (MOFs) often show extraordinary stability. However, most efforts to immobilize proteins in MOFs have only been exploratory. Herein, we present the ...first systematic study on the thermodynamics of protein immobilization in MOFs. Using insulin as a probe, we leveraged isothermal titration calorimetry (ITC) to investigate how topology, pore size, and hydrophobicity of MOFs influence immobilization. ITC data obtained from the encapsulation of insulin in a series of Zr‐MOFs reveals that MOFs provide proteins with a hydrophobic stabilizing microenvironment, making the encapsulation entropically driven. In particular, the pyrene‐based NU‐1000 tightly encapsulates insulin in its ideally sized mesopores and stabilizes insulin through π‐π stacking interactions, resulting in the most enthalpically favored encapsulation process among this series. This study reveals critical insights into the structure–property relationships of protein immobilization.
Isothermal titration calorimetry was leveraged to systematically study how the structural properties of MOFs, such as hydrophobicity, pore size, and topology, influence the thermodynamics of protein immobilization by using a series of Zr‐MOFs as the host and insulin as the model protein probe. The thermodynamics of binding can elucidate a major driving force for protein encapsulation, which could not be revealed in bulk adsorption studies.
A new set of pyrrolopyrrole‐based (PPr) polymers incorporated with thioalkylated/alkylated bithiophene (SBT/BT) is synthesized and explored as hole‐transporting materials (HTMs) for Sn‐based ...perovskite solar cells (TPSCs). Three bithiophenyl spacers bearing the thioalkylated hexyl (SBT‐6), thioalkylated tetradecyl (SBT‐14), and tetradecyl (BT‐14) chains are utilized to examine the effect of the alkyl chain lengths. Among them, the TPSCs are fabricated using PPr‐SBT‐14 as HTMs through a two‐step approach by attaining a power conversion efficiency (PCE) of 7.6% with a remarkable long‐term stability beyond 6000 h, which has not been reported elsewhere for a non‐PEDOT:PSS‐based TPSC. The PPr‐SBT‐14 device is stable under light irradiation for 5 h in air (50% relative humidity) at the maximum power point (MPP). The highly planar structure, strong intramolecular S(alkyl)···S(thiophene) interactions, and extended π‐conjugation of SBT enable the PPr‐SBT‐14 device to outperform the standard poly(3‐hexylthiophene,‐2,5‐diyl (P3HT) and other devices. The longer thio‐tetradecyl chain in SBT‐14 restricts molecular rotation and strongly affects the molecular conformation, solubility, and film wettability over other polymers. Thus, the present study makes a promising dopant‐free polymeric HTM model for the future design of highly efficient and stable TPSCs.
A new series of hydrophobic conducting polymers containing pyrrolopyrrole (PPr) and thioalkylated/alkylated bithiophene (SBT/BT) moieties is designed and synthesized to serve as hole‐transport materials (HTMs) for tin‐based perovskite solar cells to attain a power conversion efficiency of 7.6% with shelf‐storage stability over 6000 h, which opens a new avenue for future development of non‐poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) HTMs with great performance and stability.
Random copolymers, poly(l‐lactide‐r‐glycolide) are synthesized by one‐pot ring‐opening polymerization of l‐lactide and glycolide in the presence of stannous octoate and 1‐dodecanol. Block copolymers, ...poly(l‐lactide‐b‐glycolide) are synthesized by ring‐opening polymerization of l‐lactide to generate poly(l‐lactide) first and then further ring‐opening polymerization of glycolide in the presence of poly(l‐lactide) and stannous octoate. The composition ratio of l‐lactide and glycolide is determined by the integration of the corresponding signals from 1H NMR spectra, which is consistent with the feeding ratio. Very few hetero‐sequences can be observed for block copolymers due to well‐defined microstructures. The block copolymers are more thermally stable than that of the random copolymers. The degree of crystallinity of the bock copolymers is relatively high compared to that of the random copolymers. The image of the block copolymers determined by field‐emission scanning electron microscopy (FESEM) shows partial aggregate domains containing spherical particles with an average diameter of around 200 nm, which is very different from that of the random copolymers. Block copolymers are more hydrophilic than that of the random copolymers due to the ordered structure and amphiphilic behavior of the block series.
In recent years, media reports and the increased visibility of international environmental protection groups have exposed many individuals to the issue of global climate change. The present study ...investigated, from the perspective of environmental sustainability, Taiwanese university students’ purchase intentions and loyalty toward green products. A survey was administered to students in eight universities who had received 8 h of climate change education, generating a total of 1586 valid respondents. Results of structural equation modeling showed that individuals must have environmental ethics before they can become aware of their social and self-responsibility to the environment, which then increases their green product purchase intentions and consumer loyalty. This study identified the relationships between the environmental responsibility chain (environmental ethics, social responsibility, and self-responsibility), beliefs in climate change, purchase intention, and consumer loyalty toward green products. The effectiveness of adaptation strategies that reduce the psychological distance of climate change requires consideration of both temporal and spatial distances. Self-responsibility fully mediates the relationships between environmental ethics and purchase intentions and consumer loyalty, which demonstrates the importance of using more environmentally responsible strategies to promote pro-environmental behavior.
•The environmental responsibility chain consists of environmental ethics, social responsibility, and self-responsibility.•The mediating role of environmental ethics on pro-environmental behavior toward climate change was identified.•The determinants of purchase intention to green products for undergraduate students to combat climate change were explored.•Results can help practitioners promote green products to undergraduate students in developing economy countries.
Diabetic striatopathy (DS) is a rare medical condition with ambiguous nomenclature. We searched PubMed database from 1992 to 2018 for articles describing hyperglycemia associated with chorea/ballism ...and/or neuroimages of striatal abnormalities. Descriptive analysis was performed on demographic/clinical characteristics, locations of striatal abnormalities on neuroimages, pathology findings, treatment strategies, and outcomes. In total, 176 patients (male:female = 1:1.7) were identified from 72 articles with mean age 67.6 ± 15.9 (range, 8-92). Among them, 96.6% had type 2 DM with 17% being newly diagnosed. Average blood glucose and glycated hemoglobin concentrations were 414 mg/dL and 13.1%, respectively. Most patients (88.1%) presented with hemichorea/hemiballism. Isolated putamen and combined putamen-caudate nucleus involvements were most common on neuroimaging studies with discrepancies between CT and MRI findings in about one-sixth of patients. Unilateral arm-leg combination was the most frequent with bilateral chorea in 9.7% of patients. Chorea and imaging anomalies did not appear concomitantly in one-tenth of patients. Successful treatment rates of chorea with glucose-control-only and additional anti-chorea medications were 25.7% and 76.2%, respectively, with an overall recurrence rate being 18.2%. The most commonly used anti-chorea drug was haloperidol. To date, four out of six pathological studies revealed evidence of hemorrhage as a probable pathogenesis.
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