Response to external stimuli is a fundamental and intrinsic behavior of living systems. There has been increasing interest for designing and constructing responsive polymeric superstructures by ...self-assembly. Stimuli-induced self-assembly and post-assembly triggering strategies provide an alternative approach for the manipulation of self-assembled architectures of either biological or synthetic polymeric materials. Stimuli-induced structural transformations may produce ensembles with new topologies or materials with exceptionally complex features inaccessible via conventional self-assembly processes. This is in contrast to materials that simply undergo stimuli-induced degradation, or disassembly processes. Since a variety of cellular processes depend on responses to environmental stimuli that lead to more complexity and increased function, and are related to structural transitions over the nano- to microscale, insights into stimuli-triggered morphogenesis can further deepen our understanding of cellular behaviors. Indeed, an understanding of these processes will likely inspire scientists to develop materials with advanced and tailored architectures for biosensing, diagnosis and therapy as well as other biomedical applications. Herein, we highlight state-of-the-art achievements in the stimuli-triggered structural manipulation of polymer assemblies. Furthermore, future developments in this nascent and growing field are briefly discussed.
Particulate matter (PM) pollution from automobile exhaust has become one of the main pollution sources in urban environments. Although the diesel particulate filter has been used in heavy diesel ...vehicles, there is no particulate filter for most gasoline cars or light-duty vehicles because of high cost. Here, we introduce a self-powered triboelectric filter for removing PMs from automobile exhaust fumes using the triboelectrification effect. The finite element simulation reveals that the collision or friction between PTFE pellets and electrodes can generate large triboelectric charges and form a space electric field as high as 12 MV/m, accompanying an open-circuit voltage of ∼6 kV between the two electrodes, which is comparable to the measured value of 3 kV. By controlling the vibration frequency and fill ratio of pellets, more than 94% PMs in aerosol can be removed using the high electric field in the triboelectric filter. In real automobile exhaust fumes, the triboelectic filter has a mass collection efficiency of ∼95.5% for PM2.5 using self-vibration of the tailpipe.
AZ31 magnesium alloy strips have been cold-rolled to thickness reduction of 33% and followed by electropulse treatment (EPT) with different current parameters for 7s and furnace annealing for ...comparison. The results indicate that recrystallization is drastically accelerated by EPT and continuous recrystallization induced by EPT is strongly dependent on the current. Deformed coarse-grain boundaries together with extension twins (ET) bands provide sources for nucleation and are gradually consumed by recrystallization. A double peak texture was generated after recrystallization, which is associated with the promoted non-basal nucleation and the non-basal dislocations activities.
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Drug combination therapies employing dual-drug delivery systems offer an effective approach to reduce disadvantages of single-drug therapy, such as high dose and easy generation of drug resistance. ...Herein, a dual-drug delivery system based on nanogel-incorporated injectable hydrogel (NHG) was designed for sequential local delivery of combretastatin-A4 phosphate (CA4P) and doxorubicin (DOX) for antiangiogenesis and anticancer combination therapy. The injectable hydrogel was prepared for loading and quick release of hydrophilic drug CA4P, while the pH and redox stimuli-responsive nanohydrogels were incorporated into the injectable hydrogel by pH-responsive boronate ester bond for sustained long-term DOX delivery. The dual-drug-loaded NHG system released CA4P and DOX sequentially and exhibited high inhibitory activities on the cancer cell proliferation in vitro. It displayed superior therapeutic efficacy in vivo with only one single injection. Immunohistochemistry analyses suggested a synergistic therapeutic effect through tumor vascular collapse caused by CA4P and tumor cell apoptosis induced by DOX. The combination therapy of antiangiogenic and cytotoxic drugs using NHG delivery system offers a promising approach for improved cancer therapeutic efficacy. The nanogel-embedded injectable hydrogel can be employed as a universal drug carrier for local dual-drug delivery with sequential release behaviors by simple injection.
Hydrogen peroxide (H
O
) is an important signaling molecule in plant developmental processes and stress responses. However, whether H
O
-mediated signaling crosstalks with plant hormone signaling is ...largely unclear. Here, we show that H
O
induces the oxidation of the BRASSINAZOLE-RESISTANT1 (BZR1) transcription factor, which functions as a master regulator of brassinosteroid (BR) signaling. Oxidative modification enhances BZR1 transcriptional activity by promoting its interaction with key regulators in the auxin-signaling and light-signaling pathways, including AUXIN RESPONSE FACTOR6 (ARF6) and PHYTOCHROME INTERACTING FACTOR4 (PIF4). Genome-wide analysis shows that H
O
-dependent regulation of BZR1 activity plays a major role in modifying gene expression related to several BR-mediated biological processes. Furthermore, we show that the thioredoxin TRXh5 can interact with BZR1 and catalyzes its reduction. We conclude that reversible oxidation of BZR1 connects H
O
-mediated and thioredoxin-mediated redox signaling to BR signaling to regulate plant development.
Abstract Background In China, economic, urbanization, and policy differences between the eastern and western regions lead to uneven healthcare resources. This disparity is more pronounced in the west ...due to fewer healthcare personnel per thousand individuals and imbalanced doctor-to-nurse ratios, which exacerbates healthcare challenges. This study examines the spatial distribution of human resources in maternal and child healthcare from 2016 to 2021, highlighting regional disparities and offering insights for future policy development. Methods The data were sourced from the “China Health and Family Planning Statistical Yearbook” (2017) and the “China Health and Health Statistics Yearbook” (2018–2022). This study utilized GeoDa 1.8.6 software to conduct both global and local spatial autocorrelation analyses, using China’s administrative map as the base dataset. Results From 2016 to 2021, there was an upward trend in the number of health personnel and various types of health technical personnel in Chinese maternal and child healthcare institutions. The spatial distribution of these personnel from 2016 to 2021 revealed clusters characterized as high-high, low-low, high-low and low-high. Specifically, high-high clusters were identified in Guangxi, Hunan, Jiangxi, and Guangdong provinces; low-low in Xinjiang Uygur Autonomous Region and Inner Mongolia Autonomous Region; high-low in Sichuan province; and low-high in Fujian and Anhui provinces. Conclusions From 2016 to 2021, there was evident spatial clustering of health personnel and various health technical personnel in Chinese maternal and child healthcare institutions, indicating regional imbalances.
Celotno besedilo
Dostopno za:
CEKLJ, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Hypoxia and temperature stress are two major adverse environmental conditions often encountered by fishes. The interaction between hypoxia and temperature stresses has been well documented and oxygen ...is considered to be the limiting factor for the thermal tolerance of fish. Although both high and low temperature stresses can impair the cardiovascular function and the cross-resistance between hypoxia and heat stress has been found, it is not clear whether hypoxia acclimation can protect fish from cold injury.
Pre-acclimation of 96-hpf zebrafish larvae to mild hypoxia (5% O2) significantly improved their resistance to lethal hypoxia (2.5% O2) and increased the survival rate of zebrafish larvae after lethal cold (10°C) exposure. However, pre-acclimation of 96-hpf larvae to cold (18°C) decreased their tolerance to lethal hypoxia although their ability to endure lethal cold increased. RNA-seq analysis identified 132 up-regulated and 41 down-regulated genes upon mild hypoxia exposure. Gene ontology enrichment analyses revealed that genes up-regulated by hypoxia are primarily involved in oxygen transport, oxidation-reduction process, hemoglobin biosynthetic process, erythrocyte development and cellular iron ion homeostasis. Hypoxia-inhibited genes are enriched in inorganic anion transport, sodium ion transport, very long-chain fatty acid biosynthetic process and cytidine deamination. A comparison with the dataset of cold-regulated gene expression identified 23 genes co-induced by hypoxia and cold and these genes are mainly associated with oxidation-reduction process, oxygen transport, hemopoiesis, hemoglobin biosynthetic process and cellular iron ion homeostasis. The alleviation of lipid peroxidation damage by both cold- and hypoxia-acclimation upon lethal cold stress suggests the association of these genes with cold resistance. Furthermore, the alternative promoter of hmbsb gene specifically activated by hypoxia and cold was identified and confirmed.
Acclimation responses to mild hypoxia and cold stress were found in zebrafish larvae and pre-acclimation to hypoxia significantly improved the tolerance of larvae to lethal cold stress. RNA-seq and bioinformatics analyses revealed the biological processes associated with hypoxia acclimation. Transcriptional events co-induced by hypoxia and cold may represent the molecular basis underlying the protection of hypoxia-acclimation against cold injury.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The ultrafast photonics of different conventional two-dimensional (2D) materials have been studied intensively. Few-layer structure bismuthene has been reported as a new type of 2D material with high ...efficient electronics, strong mechanics and outstanding photonics properties. In this paper, a robust ultrafast pulse generation in communications-Band (C-Band) based on few-layer bismuthene has been reported. The characteristics and the ultrafast optical nonlinear properties of few-layer bismuthene have been investigated experimentally. The optical induced deposition method is employed to fabricate the saturable absorber based on bismuthene (BiSA). Most importantly, we also utilize BiSA for the ultrafast photonics, which demonstrates that a high-splitting-threshold robust ultrafast fiber laser with 1.3-ps pulse duration at 1531 nm has been obtained in the experiments. Even though we increase the pump power from the self-starting threshold (i.e. 86 mW) to 314 mW, the soliton pulse does not split. Moreover, the high-splitting-threshold laser operation can be achieved stably even if the lasers are exposed in air for at least half a year. It is demonstrated that the proposed bismuthene nonlinear components can be potentially applied to the optical communications with C-Band (i.e. 1530-1565 nm wavelength) to broaden the communications window.
Peripheral inflammation-induced chronic pain tends to evoke concomitant anxiety disorders. It's common knowledge that the anterior cingulate cortex (ACC) plays a vital role in maintaining pain ...modulation and negative emotions. However, the potential mechanisms of chronic inflammation pain and pain-related anxiety remain elusive. Here, it was reported that injecting complete Freund's adjuvant (CFA) unilaterally resulted in bilateral mechanical allodynia and anxiety-like symptoms in mice via behavioral tests. In addition, CFA induced the bilateral upregulation and activation of calcium homeostasis modulator 2 (Calhm2) in ACC pyramidal neurons by quantitative analysis and double immunofluorescence staining. The knockdown of Calhm2 in the bilateral ACC by a lentiviral vector harboring ribonucleic acid (RNA) interference sequence reversed CFA-induced pain behaviors and neuronal sensitization. Furthermore, the modulating of ACC pyramidal neuronal activities via a designer receptor exclusively activated by designer drugs (DREADD)-hM4D(Gi) greatly changed Calhm2 expression, mechanical paw withdrawal thresholds (PWTs) and comorbid anxiety symptoms. Moreover, it was found that Calhm2 regulates inflammation pain promoting the upregulation of N-methyl-D-aspartic acid (NMDA) receptor 2B (NR2B) subunits. Calhm2 knockdown in ACC exhibited a significant decrease in NR2B expression. These results demonstrated that Calhm2 in ACC pyramidal neurons modulates chronic inflammation pain and pain-related anxiety symptoms, which provides a novel underlying mechanism for the development of inflammation pain.
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