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In this article, a high step-up hybrid Y-source-quasi-Z source dc–dc converter is obtained by combining the topology of Y-source and quasi-Z source. The proposed converter inherits all the advantages of Y-source and quasi-Z source converter, namely continuous input current, common ground between input and output voltages, built-in step-down transformer, low voltage stress of switch, and low output diode current stress. In addition, the proposed converter has high voltage gain and conversion efficiency. The steady-state analysis and voltage and current stress derivation are presented. A numerical design of the components is conducted. The loss distribution is precisely calculated. The conversion efficiency at different voltage gains was also investigated. A small signal model is composed. Then the stability of the system is studied and optimized by PID compensator. Finally, a 160-W prototype made in the laboratory verified the effectiveness of the proposed converter, and the efficiency reached 95.201% when operating at rated output power. The proposed converter has the highest experimental efficiency with respect to the other compared converters.

Ethylenediamine tetramethylenephosphonic acid (EDTMPA) incorporated in the catalysts layer is a facile strategy to construct an efficient electrocatalytic reaction interface to enhance the reactivity, durability, and utilization of the electrocatalysts in HT-PEMFCs.

UbiA-type prenyltransferases (PTases) are significant enzymes that lead to structurally diverse meroterpenoids. Herein, we report the identification and characterization of an undescribed UbiA-type PTase, FtaB, that is responsible for the farnesylation of indole-containing diketopiperazines (DKPs) through genome mining. Heterologous expression of the ftagene cluster and non-native pathways result in the production of a series of new C2-farnesylated DKPs. This study broadens the reaction scope of UbiA-type PTases and expands the chemical diversity of meroterpenoids.

While network resources are scarce and there are a variety of network mission demands in the space-terrestrial network, due to weak resource management low utilization efficiency makes multiple missions unachievable. The intent-driven networks present a possible way to guarantee autonomous and reliable services according to users' declarative intents, so that users no longer need to focus on how to implement the management and configuration details. In this article, we define coordination, collaboration, and cooperation as CoX, and propose an intent-driven CoX scheme to match resource agents and mission agents. It focuses on satisfying the requirements of complex missions and providing on-demand network services by exploring and exploiting the capabilities of intent-driven networks. To be specific, the intent-driven CoX scheme consists of the coordination intent decomposition, the collaboration intent management, and the cooperation resource management. To demonstrate the main features and performance, we also provide a proof of concept implementation of the intent-driven CoX scheme.

In this article, a novel three-winding coupled inductor (TWCL) based high-gain dc–dc converter is proposed, which combines a TWCL technique and a voltage multiplier cell, avoiding large duty cycle and resulting in a high gain of the converter. The input current continuity and common ground make the proposed converter suitable for renewable energy. In addition, the converter also has the characteristics of low voltage stress on switch and high efficiency. A passive clamp circuit recycles the energy stored in the leakage inductor of the coupled inductor and reduces the voltage spike of the switch, thus improving efficiency. The steady-state analysis, parameter design, and loss analysis of the proposed converter are discussed in detail, and the comparison among existing high-gain converters is discussed as well. Finally, experimental results verify the theoretical analysis.

In this article, a modified quasi-Z-source high step-up dc–dc converter is suggested for renewable energy applications, which features lower voltage stress of switch and wider region of duty cycle control. In addition, the superiority of the novel converter embodies ultrahigh voltage gain with a small turns ratio of coupled inductor, continuous input current, and an adjustable wide range of voltage gain. From coupled inductor, a step-down type winding (turn ratio less than 1) and a step-up type winding (turn ratio more than 1) not only enhance the voltage gain, but also provide more flexible voltage regulation. The low pulsating input current can decrease the volume and capacity of the input filter. Moreover, the switched-capacitor contains an internal passive clamp circuit for the power switch, which can alleviate the voltage spike during turn-off operation and restore the leakage inductor energy. The operating principle and theoretical analysis of the converter are given in detail. A 200-W prototype was fabricated in the laboratory according to the design guideline, and the experimental results verify the validity of analysis.

Phosphoric acid (PA) is a vital proton-conducting medium for high-temperature proton exchange membrane fuel cells (HT-PEMFCs); however, regulating its distribution to decrease poisoning on the electrocatalysts and maintain elevated reactivity durability remains a significant challenge. In this work, defective g-C3N4(D-C3N4) was incorporated into Pt/C catalyst layers to promote PA distribution for enhancing the intrinsic reactivity expression of catalysts. Following decoration of D-C3N4, HT-PEMFCs with low Pt loading in both the anode (0.20 mgPtcm−2) and the cathode (0.40 mgPtcm−2) exhibited a high peak power density of 672 mW cm−2and excellent high reactivity durability (above 620 mW cm−2) after accelerated 3500 cycles, which is far superior to previously published results. This work first reveals that the acid/base interaction of D-C3N4with PA modulates PA distribution in the catalytic layer, thereby enhancing the intrinsic reactivity expression and utilization efficiency of catalysts in HT-PEMFCs.

This article presents a novel nonisolated high step-up dc-dc converter for renewable energy generation systems. The converter combines a three-winding coupled inductor (CI), voltage multiplier cells (VMCs), and two power switches with simultaneous operation. Compared with existing high step-up converters, the proposed converter can achieve high voltage gain under a low number of turns ratio while avoiding a large duty cycle. Moreover, the passive clamp circuit recycles leakage inductor energy and reduces the voltage spike of switches. The continuity of input current and existence of common ground between the input energy source and load make the converter suitable for renewable energy applications. Also, the proposed converter shares high voltage gain with low voltage stress on semiconductors (switches/diodes), improved compactness, and high efficiency. The operating principles and steady-state analysis of the proposed converter are illustrated. Then the theoretical efficiency analysis and performance comparison with other converters are discussed. Finally, a 200 W prototype with 380 V output voltage is established based on the design guidelines, and experimental results verify the accuracy of the theoretical analysis.

It is necessary to understand the molecular mechanism of banana dwarfing mutation in order to improve the high stem character of banana varieties and breed the new excellent dwarf lines. To elucidate the molecular-level regulation of banana dwarf mutations and identify the relevant genes, the complete cDNA sequence of the gibberellin 2-oxidase gene (GA2ox) in the dwarf banana and its wild type was cloned by RT-PCR and the encoded amino acid sequences bioinformatically was analyzed. Meanwhile, the expression levels of banana GA2oxgene in different tissues of dwarfed banana and its wild type were analyzed by qRT-PCR. Between the GA2oxgene sequences of the dwarf banana and its wildtype, there were 5 base pairs of variation, leading to the predicted GA2ox proteins having different molecular weights, isoelectric points, fat indices, total numbers of positive and negative charges, and hydrophilicity. In addition, the expression of GA2oxin the leaves, stalks, and fruits of dwarf banana plants was higher than that in the wild type in the early and middle stages of banana development. The results showed that the GA2oxgene may have important regulatory effects on banana stem dwarfing, the knowledge of which can help our understanding and manipulation of this important plant.

Effective tuning of carrier dynamics in two-dimensional (2D) materials is significant for multi-scene device applications. Using first-principles and ab initiononadiabatic molecular dynamics calculations, the kinetics of O2, H2O, and N2intercalation into 2D WSe2/WS2van der Waals heterostructures and its effect on carrier dynamics have been comprehensively explored. It is found that the O2molecule prefers to dissociate into atomic O atoms spontaneously after intercalation of WSe2/WS2heterostructures, whereas H2O and N2molecules remain intact. O2intercalation significantly speeds up the electron separation process, while H2O intercalation largely speeds up the hole separation process. The lifetime of excited carriers can be prolonged by O2or H2O or N2intercalations. These intriguing phenomena can be attributed to the effect of interlayer coupling, and the underlying physical mechanism for tuning the carrier dynamics is fully discussed. Our results provide useful guidance for the experimental design of 2D heterostructures for optoelectronic applications in photocatalysts and solar energy cells.

Antibiotic pretreatment is routine for chronic dacryocystitis (DC) patients. Herein, the longitudinal effects of antibiotic pretreatment before dacryocystorhinostomy for DC patients were evaluated. Conjunctival and nasal swabs were collected longitudinally from 33 DC patients with and without antibiotic pretreatment, both before dacryocystorhinostomy and at 1, 2, and 4 weeks postdacryocystorhinostomy. Additionally, conjunctival sac swabs were collected from 46 healthy volunteers and 14 other ocular diseases patients. Comparisons focused on ocular/nasal microbiota and recovery outcomes. Compared to healthy participants, DC patients without antibiotic pretreatment exhibited greater ocular microbiota diversity before dacryocystorhinostomy. Although clinical recovery rates were comparable, our results suggest that, after antibiotic pretreatment, the ocular microbiota richness and diversity, and the composition alteration tendency, significantly changed 4 weeks after surgery. This implies that the ocular microbiota was more disturbed in patients who underwent antibiotic pretreatment compared to those without such treatment. Furthermore, two types of ocular microbiota and three types of nasal microbiota were identified in ocular diseases. This study provides comprehensive data on the ocular and nasal microbiota in DC patients with and without antibiotic pretreatment, along with other ocular diseases. This finding suggested that antibiotic pretreatment may not be necessary before dacryocystorhinostomy for DC patients, especially for nonsevere cases. Two types of ocular microbiota and three types of nasal microbiota were demonstrated among ocular diseases patients. Although clinical recovery is comparable, the antibiotic pretreatment significantly changed the ocular microbiota 4 weeks after dacryocystorhinostomy, which suggested the antibiotic is not needed for recovery from dacryocystorhinostomy. An altered ocular microbiota could potentially be used to assist in chronic dacryocystitis diagnosis. Two types of ocular microbiota and three types of nasal microbiota were demonstrated among ocular diseases patients.Although clinical recovery is comparable, the antibiotic pretreatment significantly changed the ocular microbiota 4 weeks after dacryocystorhinostomy, which suggested the antibiotic is not needed for recovery from dacryocystorhinostomy.An altered ocular microbiota could potentially be used to assist in chronic dacryocystitis diagnosis. Two types of ocular microbiota and three types of nasal microbiota were demonstrated among ocular diseases patients. Although clinical recovery is comparable, the antibiotic pretreatment significantly changed the ocular microbiota 4 weeks after dacryocystorhinostomy, which suggested the antibiotic is not needed for recovery from dacryocystorhinostomy. An altered ocular microbiota could potentially be used to assist in chronic dacryocystitis diagnosis.

Activating the efficient electron transfer in oxygen evolution reaction (OER) by tuning the oxygen (O) electronic states near the Fermi level is essential to break the linear scaling limitation of OER intermediates. Herein, we construct a series of rare earth (RE) single atoms on MnO2nanosheets with modulated oxygen states by an effective and universal Ar plasma (P)-assisted strategy (P-RE SAs@MnO2, RE = Gd, La, Ce, Tm, and Lu) to investigate the origin of RE-enhanced OER performance. Taking P-Gd SAs@MnO2as a representative, the atomically dispersed Gd atoms on MnO2assist the construction of localized asymmetric [Gd−O−Mn] units, which induces electron accumulation at surrounding oxygen sites by introducing the polarized ionic Gd−O bond. As a result, the P-Gd SAs@MnO2delivers impressive OER performance with low overpotential (281 mV@10 mA cm −2; ηj10), robust long-term stability, and optimized activation energy (Ea= 32.07 kJ mol−1at ηj10), which are superior to RE-free MnO2, commercial RuO2,and most Mn-based catalysts. Similar enhanced OER performance can also be found for other P-RE SAs@MnO2(RE = La, Ce, Tm, and Lu). X-ray absorption and in situRaman spectroscopy unveil the preferred electron accumulation at Mn−O, promoting the formation of terminal MnIV=O intermediates in OER. Theoretical calculations demonstrate that the construction of [Gd−O−Mn] unit endows the surface lattice unsaturated O site with the labile property, which assists the direct formation of (O−O) dimer for circumventing the universal scaling relation applied by the formation of *OOH. This work opens up a new avenue for the design of transition metal oxides with modulated oxygen state to break the limitation of the adsorbate evolution mechanism during OER.

[Display omitted] • The morphology of Cu was tailored by controlling the ripening time of Cu seeds. • Biosensors by the Cu NPs showed a superior thermostability and sensitivity. • The 2D nanostructure enabled Cu to exhibit a wide detection range toward glucose. • This work would open up a new avenue for utilizing non-noble metals. In this study, we demonstrated a one-pot synthesis of Cu nanoplates (Cu NPs) with high purity and "clean surface". Different from surfactant-assisted method, we tailored the architecture by controlling the ripening time of Cu seeds. Citrate is introduced as a structure-directing agent. Since the "clean surface" provide more available active sites, the as-prepared Cu NPs show a superior performance when utilized in the non-enzymatic biosensors. In the detection of nitrite, the sensor constructed by Cu NPs exhibited a superior sensitivity (303.1 ± 10.18 µA·mM−1·cm−2), and the detection range is 5.0 mM. On the contrary, sensitivity for the Cu NPs by surfactant-assisted method is negligible. As applied in the glucose sensors, detection range by Cu NPs could reach 36.0 mM. And the sensitivity under ambient condition (298 K) is 561.93 ± 3.72 µA·mM−1·cm−2, which is ca. 2.11-folds higher than that for Cu NPs by surfactant-assisted method. In the detection of H 2 O 2 , detection range is 10.0 mM, and the enhancement factor for detection range is up to 2.0-folds. The superior performance can also be extended to the catalysis for the reduction of 4-nitro-phenol. Since no additional noble metals was applied, this strategy would open up a new avenue for utilizing non-noble metals. [ABSTRACT FROM AUTHOR]

Objectives: Few studies comparing the effects of different types of Tai Chi exercises on preventing falls in older adults. We compared the effects for finding an optimal intervention. Methods: We searched 12 databases, including PubMed, EMBASE, Cochrane Library, Chinese National Knowledge Infrastructure (CNKI) and so on, from their inception to January 13, 2023. Randomized controlled trials incorporating different types of Tai Chi for preventing falls in older adults were included. The outcome measures were the incidence of falls and Berg Balance Scale (BBS). Network meta-analysis (NMA) was conducted using Stata 15.1 based on a frequentist framework. Results: Seventeen trials were eligible, including 3470 participants and four types of Tai Chi. They were 24-form simplified Tai Chi (24-form), Yang style Tai Chi (Yang style), Sun style Tai Chi (Sun style) and Tai Chi exercise program (TCEP). In paired meta-analysis, for incidence of falls, 24-form (Relative Risk (RR) = 0.59, 95% confidence interval (CI) [0.40, 0.86]) was more efficient than the control group. For BBS outcome, 24-form (MD (mean difference) = 2.32, 95% CI [1.42, 3.22]) was better than the control group. In the NMA, the results of incidence of falls were as follows: 24-form > Yang style > Sun style > control > TCEP. The rank probability of BBS was as follows: 24-form > TCEP > Yang style > control. Conclusion: Among the four types of Tai Chi studied, the 24-form simplified Tai Chi has shown better efficacy than other types.

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Fibromyalgia (FM) is a complex and poorly understood disorder characterized by chronic and widespread musculoskeletal pain, of which the etiology remains unknown. Now, the disorder of the gut microbiome is considered as one of the main causes of FM. This study aimed to investigate the potential benefits of fecal microbiota transplantation (FMT) in patients with FM. A total of 45 patients completed this open-label, randomized, nonplacebo-controlled clinical study. The numerical rating scale scores in the FMT group were slightly lower than the control group at 1 month (P > .05), and they decreased significantly at 2, 3, 6, and 12 months after treatment (P < .001). Besides, compared with the control group, the Widespread Pain Index, Symptom Severity, Hospital Anxiety and Depression Scale, and Pittsburgh Sleep Quality Index scores were significantly lower in the FMT group at different time points (P < .001). After 6 months of treatment, there was a significant increase in serotonin (5-hydroxytryptamine) and gamma-aminobutyric acid levels (P < .001), while glutamate levels significantly decreased in the FMT group (P < .001). The total effective rate was higher in the FMT group (90.9%) compared to the control group (56.5%) after 6 months of treatment (P < .05). FMT can effectively improve the clinical symptoms of FM. With the close relations between the changes in neurotransmitters and FM, certain neurotransmitters may serve as a diagnostic marker or potential target for FM patients.

Autism spectrum disorder (ASD) is a prevalent neurodevelopmental disorder with a complex etiology. Recent evidence suggests that dopamine plays a crucial role in neural development. However, it remains unclear whether and how disrupted dopaminergic signaling during development contributes to ASD. In this study, human brain RNA-seq transcriptome analysis revealed a significant correlation between changes in dopaminergic signaling pathways and neural developmental signaling in ASD patients. In the zebrafish model, disrupted developmental dopaminergic signaling led to neural circuit abnormalities and behavior reminiscent of autism. Dopaminergic signaling may impact neuronal specification by potentially modulating integrins. These findings shed light on the mechanisms underlying the link between disrupted developmental dopamine signaling and ASD, and they point to the possibility of targeting dopaminergic signaling in early development for ASD treatment.

This paper proposes a discrete space vector modulation and optimized switching sequence model predictive controller for three-level neutral-point-clamped inverters in grid-connected applications. The proposed strategy is based on cascaded model predictive control (MPC) for controlling the grid current while maintaining the capacitor voltage balanced without weighting factor. To enhance the closed-loop performance, the external MPC evaluates 19 basic and 138 virtual vectors (VV) of the proposed space vector method. The optimal control voltage is then selected using an extended deadbeat method to reduce the execution time of the proposed control algorithm. By using the discrete space vector modulation principle, the VV are synthesized based on switching sequence (SS) and are divided into negative and positive SSs considering their impact on the neutral point (NP) potential. The inner MPC evaluates both types of SSs and selects the one that keeps the capacitor voltage balanced. Various controllers are evaluated and compared against the proposed control strategy. The results show that the proposed strategy improves performance without weighting factor, while maintaining a total harmonic distortion of current to be less than 2%. Compared to the modulated MPC which provides the same fixed switching frequency, the proposed controller reduces the computational burden by over 50% while also providing better NP voltage balance accuracy.

With the inspiration of the shape of the loquat fruit, here, we developed a similarly shaped Janus carrier. This peculiar gold rod-partially exposed structure not only significantly increased the drug loading capability but also improved its infrared response efficiency. A better effect of drug-photothermal treatment thus could be realized. With the aid of an external 3D printed drug guiding device, this carrier could accurately reach different affected areas. The subsequent infrared triggered multiple tumor therapy, thus, could be conducted in the designated location. The corresponding experimental results demonstrated the reliability, flexibility, and biocompatibility of the proposed drug delivery system for two different tumor targeting treatments.

Inspired by the fact that chitosan is a representative constituent of the ectocellular structure of Cryptococcus neoformansand a typical biomaterial for improving drug oral absorption, we designed an elegant and efficient C. neoformans-targeted drug delivery system via oral administration. A chitosan-binding peptide screened by phage display was used as the targeting moiety, followed by conjugation to the surface of poly(lactic-co-glycolic acid) nanoparticles as the drug carrier, which was then incubated with free chitosan. The noncovalently bound chitosan adheres to mucus layers and significantly enhances penetration of nanoparticles through the oral absorption barrier into circulation and then re-exposed the targeting ligand for later recognition of the fungal pathogen at the site of infection. After loading itraconazole as a model drug, our drug delivery system remarkably cleared lung infections of C. neoformansand increased survival of model mice. Currently, targeted drug delivery is mainly performed intravenously; however, the system described in our study may provide a universal means to facilitate drug targeting to specific tissues and disease sites by oral administration and may be especially powerful in the fight against increasingly severe fungal infections.

The effects of KTN and KTN@Ag nanoparticles on dielectric behavior and temperature-dependent dielectric mechanisms of PVDF-based composites were studied. It was found that relatively high dielectric permittivity, low loss tangent, and outstanding dielectric stability were simultaneously achieved in the Nano-KTN@Ag/PVDF hybrid films. In this study, we found that the effect of interfacial polarization on the permittivity of Nano-KTN@Ag/PVDF hybrid film becomes more and more significant with the increase of temperature. The calculated conductivity activation energy (EA) proved that the migration of charge carriers requires more energy to overcome the potential barrier in the Nano-KTN@Ag/PVDF hybrid films than that in the Nano-KTN/PVDF hybrid films. A complete and systematic study of the dielectric mechanism is necessary, which can be a significant guide to the preparation of dielectric materials applied in the electronics industry.

Tumors managing to exempt from immune clearance are attributable to their overexpressed immune suppressive molecules (CD47, PD-L1, etc.). Leadingly, the checkpoint blockade-based chemoimmunotherapy by means of knockdown of these immunosuppressive checkpoints, together with immunogenetic chemotherapeutics, is perceived to be a valid therapeutic strategy for improving anti-tumor outcomes. Herein, chemotherapeutic camptothecin was covalently introduced into an intriguing multifaceted nanomedicine. Note that the elaborated nanomedicine was chemically engineered to enable targeted transportation to the tumors via systemic administration, possessing intelligent responsiveness to sequential extracellular and intracellular microenvironments in the targeted tumors for prompted transcellular endocytosis owing to enzymolysis by the tumor-enriched matrix metalloproteinases and the selective liberation of cytocidal camptothecin in the cell interiors owing to thiolysis by glutathione. In addition, this chemotherapeutic nanomedicine allowed facile encapsulation of the negatively charged RNA interference payloads. Consequently, aiming for treatment of intractable triple-negative breast tumors, we attempted the small interfering RNA (siRNA) payloads aiming for CD47 and PD-L1 into the aforementioned nanomedicine. The subsequent investigations demonstrated drastic knockdown of these vital immune suppressive checkpoints by this siRNA-encapsulating chemotherapeutic nanomedicine, conducing to the reversal of the immune checkpoint suppressive microenvironment of triple-negative 4T1 tumors. Namely, the inhibited proceedings of the innate and adaptive anti-tumor immunities were revived, as supported by observation of the activated infiltration and retention of CD68+macrophages and CD4+and CD8+lymphocytes into the tumors. Eventually, most potent anti-tumor efficacies were accomplished by systemic administration of this chemoimmunotherapeutic nanomedicine, which verified the amplified contribution from anti-tumor immunities by means of knockdown of the immune suppressive molecules to the ultimate anti-tumor efficacies. Note that the upregulation of the immune suppressive molecules was constantly reported in a variety of clinical therapies; hence, our facile chemoimmunotherapeutic platform should be emphasized in clinical translation for seeking improved therapeutic outcomes.

In electrochemical energy devices, the operating conditions always exert enormous influence on electrocatalysts’ performances. Phosphoric acid (PA), acted as the proton carriers, can be adsorbed on Pt surface, block active sites and affect the electronic structure of Pt unfavorably, which severely restricts the performance of high-temperature proton exchange membrane fuel cells (HT-PEMFCs). Herein, simply basic organic compounds, such as dicyandiamide (DCD), melamine (Mel) and cyanuric acid (CA), are decorated on Pt surface (DCD-Pt/C, Mel-Pt/C and CA-Pt/C) to induce the adsorption transfer of proton carriers. The decoration can not only inject electrons to Pt and enhance oxygen reduction reaction (ORR) activity but also can induce PA to transfer from Pt surface to organic compounds, decontaminating active sites. In addition, the organic compounds with the larger conjugated system and the smaller electronegativity of ligating atoms would have a greater interaction with Pt, causing a larger decoration amount on Pt surface, which leads to more excellent ORR activity and resistance to PA blockage effect. Therefore, Mel-Pt/C shows a peak power density of 629 mW/cm2, exceeding commercial Pt/C (437 mW/cm2), DCD-Pt/C (539 mW/cm2) and CA-Pt/C (511 mW/cm2) with the same loading.

Spinal cord injury (SCI) is an incurable trauma that frequently results in partial or complete loss of motor and sensory function. Massive neurons are damaged after the initial mechanical insult. Secondary injuries, which are triggered by immunological and inflammatory responses, also result in neuronal loss and axon retraction. This results in defects in the neural circuit and a deficiency in the processing of information. Although inflammatory responses are necessary for spinal cord recovery, conflicting evidence of their contributions to specific biological processes have made it difficult to define the specific role of inflammation in SCI. This review summarizes our understanding of the complex role of inflammation in neural circuit events following SCI, such as cell death, axon regeneration and neural remodeling. We also review the drugs that regulate immune responses and inflammation in the treatment of SCI and discuss the roles of these drugs in the modulation of neural circuits. Finally, we provide evidence about the critical role of inflammation in facilitating spinal cord neural circuit regeneration in zebrafish, an animal model with robust regenerative capacity, to provide insights into the regeneration of the mammalian central nervous system.

The effects of the morphology, interface, and dielectric constant of inorganic fillers on the dielectric properties of nanocomposites were systemically studied in this paper. It is found that two kinds of KTa0.5Nb0.5O3(KTN) nanoparticles, synthesized via solid-state reaction and hydrothermal method respectively, can bring different influences on the structure and electrical performance of the KTN/PVDF composites. This is caused by the OH groups on the surface of the H-KTN nanoparticles which were generated through the hydrothermal method. Theoretical models, including the Maxwell–Garnett model, logarithmic model, Jayasundere–Smith model, effective medium theory model, and Weibull distribution method, are employed to explain the dielectric behavior of the composite. Through the comparison between the experimental data and theoretical models, it is concluded that the geometric shape of fillers plays a more crucial role than the dielectric constant of fillers in enhancing the dielectric constant of KTN/PVDF composite films. Consequently, it is an effective way to fabricate the composites with excellent dielectric properties by modulating the geometric shape of inorganic fillers.

Biological membranes are normally under a resting transmembrane potential (TMP), which originates from the ionic imbalance between extracellular fluids and cytosols, and serves as electric power storage for cells. In cell electroporation, the ionic imbalance builds up a high TMP, resulting in the poration of cell membranes. However, the relationship between ionic imbalance and TMP is not clearly understood, and little is known about the effect of ionic imbalance on the structure and dynamics of biological membranes. In this study, we used coarse-grained molecular dynamics to characterize a dipalmitoylphosphatidylcholine bilayer system under ionic imbalances ranging from 0 to ∼0.06 echarges per lipid (e/Lip). We found that the TMP displayed three distinct regimes: 1) a linear regime between 0 and 0.045 e/Lip, where the TMP increased linearly with ionic imbalance; 2) a yielding regime between ∼0.045 and0.060 e/Lip, where the TMP displayed a plateau; and 3) a poration regime above ∼0.060 e/Lip, where we observed pore formation within the sampling time (80 ns). We found no structural changes in the linear regime, apart from a nonlinear increase in the area per lipid, whereas in the yielding regime the bilayer exhibited substantial thinning, leading to an excess of water and Na+within the bilayer, as well as significant misalignment of the lipid tails. In the poration regime, lipid molecules diffused slightly faster. We also found that the fluid-to-gel phase transition temperature of the bilayer dropped below the normal value with increased ionic imbalances. Our results show that a high ionic imbalance can substantially alter the essential properties of the bilayer, making the bilayer more fluid like, or conversely, depolarization of a cell could in principle lead to membrane stiffening.

Cationic nanoparticles (NPs) and cell-penetrating peptides (CPPs) can enter cells in an energy-independent fashion, escaping the traditional endocytosis route, which is known as direct translocation. This unconventional entry, usually complementary to endocytosis, features rapid uptake and thus makes both cationic NPs and CPPs fascinating intracellular delivery agents. However, the mechanisms of the direct translocation of both cationic NPs and CPPs across cell membranes into the cytosol are not understood. Moreover, the relationship between direct translocation and endocytosis is also unclear. Here, using coarse-grained molecular dynamics simulations we show that a model cell membrane generates a nanoscale hole to assist the spontaneous translocation of cationic gold nanoparticles (AuNPs) as well as HIV-1 Tat peptides to the cytoplasm side under a transmembrane (TM) potential. After translocation, the AuNPs/Tat peptides move freely in the “cytoplasm” region and the membrane reseals itself within a microsecond, while the TM potential is strongly diminished. Furthermore, we show that the shape of the cationic object is crucial in determining if it can translocate or not across. The results provide insights into the uptake kinetics of cationic NPs/CPPs, which features the relationship between direction translocation and endocytosis. The mechanism put forward here establishes fundamental principles of the intracellular delivery of cationic nanocarriers.

Evidence shows that chronic prostatitis/chronic pelvic pain syndrome hugely impacts the body and mind. The central mechanisms in patients with CP/CPPS resulted in increased attention as neuroimaging techniques developed. This review investigated the study design and major neuroimaging findings in CP/CPPS patients to provide comprehensive evidence. Seven databases were searched and screened: PubMed, EMBASE/SCOPUS, Cochrane Library Database, China National Knowledge Infrastructure, VIP, Wanfang, and China Biology Medicine disc. Nine studies were eventually included in the analysis. The results demonstrate that the insula, anterior cingulate gyrus, postcentral gyrus, and precuneus are significantly associated with CP/CPPS patients’ pain feelings and cause dysregulation of painful emotions, lowering patients’ tolerance to stimulus.

A series of novel nano-silica-alumina co-doped polyimide (PI/nano-SiO2-Al2O3) three-layer composite films were prepared viacombination of sol-gel process and ultrasonic-mechanical method. The effects of different inorganic phase contents and different Si/Al weight ratio on the properties of composites were investigation. The amination process of PI composite films was analyzed by Fourier transform infrared (FT-IR), and the inorganic phases’ morphology and its distribution in composite films were observed by scanning electron microscopy (SEM). Results indicated that a homogeneous dispersion of SiO2-Al2O3particles was obtained when the inorganic phase content was below 6 wt.%. The thermal and mechanical properties of the three-layer composite films were measured and compared to the pure PI. It was also observed that when Si/Al weight ratio was 4:1 and the total inorganic phase weight content reached 4 wt.%, the composite film had the highest tensile strength, which was 30% higher than pure PI. Moreover, the electric breakdown strength of composite films was examined and its effective factors were analysed.

Nanoparticle penetration into cell membranes is an interesting phenomenon that may have crucial implications on the nanoparticles’ biomedical applications. In this paper, a coarse-grained model for gold nanoparticles (AuNPs) is developed (verified against experimental data available) to simulate their interactions with model lipid membranes. Simulations reveal that AuNPs with different signs and densities of surface charges spontaneously adhere to the bilayer surface or penetrate into the bilayer interior. The potential of mean force calculations show that the energy gains upon adhesion or penetration is significant. In the case of penetration, it is found that defective areas are induced across the entire surface of the upper leaflet of the bilayer and a hydrophilic pore that transports water molecules was formed with its surrounding lipids highly disordered. Penetration and its concomitant membrane disruptions can be a possible mechanism of the two observed phenomena in experiments: AuNPs bypass endocytosis during their internalization into cells and cytotoxicity of AuNPs. It is also found that both the level of penetration and membrane disruption increase as the charge density of the AuNP increases, but in different manners. The findings suggest a way of controlling the AuNP−cell interactions by manipulating surface charge densities of AuNPs to achieve designated goals in their biomedical applications, such as striking a balance between their cellular uptake and cytotoxicity in order to achieve optimal delivery efficiency as delivery agents.