Search

In this work, we investigated the effect of hole transporting poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) interfacing with Mn-doped CdS/ZnS quantum dots (QDs) deposited on an indium tin oxide (ITO) substrate on the photoemission of upconverted hot electrons under weak continuous wave photoexcitation in a vacuum. Among the various factors that can influence the photoemission of the upconverted hot electrons, we studied the role of PEDOT:PSS in facilitating the hole transfer from QDs and altering the energy of photoemitted hot electrons. Compared to hot electrons emitted from QDs deposited directly on the ITO substrate, the addition of the PEDOT:PSS layer between the QD and ITO layers increased the energy of the photoemitted hot electrons. The increased energy of the photoemitted hot electrons is attributed in part to the reduced steady-state positive charge on the QDs under continuous photoexcitation, which reduces the energy required to eject the electron from the conduction band. [ABSTRACT FROM AUTHOR]

Traditional Chinese Medicines (TCMs) have been used for centuries for the treatment and management of various diseases. However, their effective delivery to targeted sites may be a major challenge due to their poor water solubility, low bioavailability, and potential toxicity. Nanocarriers, such as liposomes, polymeric nanoparticles, inorganic nanoparticles and organic/inorganic nanohybrids based on active constituents from TCMs have been extensively studied as a promising strategy to improve the delivery of active constituents from TCMs to achieve a higher therapeutic effect with fewer side effects compared to conventional formulations. This review summarizes the recent advances in nanocarrier-based delivery systems for various types of active constituents of TCMs, including terpenoids, polyphenols, alkaloids, flavonoids, and quinones, from different natural sources. This review covers the design and preparation of nanocarriers, their characterization, and in vitro/vivo evaluations. Additionally, this review highlights the challenges and opportunities in the field and suggests future directions for research. Nanocarrier-based delivery systems have shown great potential in improving the therapeutic efficacy of TCMs, and this review may serve as a comprehensive resource to researchers in this field. [ABSTRACT FROM AUTHOR]

2D hybrid organic–inorganic perovskites (HOIPs) are commonly found under subcritical cyclic stresses and suffer from fatigue issues during device operation. However, their fatigue properties remain unknown. Here, the fatigue behavior of (C4H9‐NH3)2(CH3NH3)2Pb3I10, the archetype 2D HOIP, is systematically investigated by atomic force microscopy (AFM). It is found that 2D HOIPs are much more fatigue resilient than polymers and can survive over 1 billion cycles. 2D HOIPs tend to exhibit brittle failure at high mean stress levels, but behave as ductile materials at low mean stress levels. These results suggest the presence of a plastic deformation mechanism in these ionic 2D HOIPs at low mean stress levels, which may contribute to the long fatigue lifetime, but is inhibited at higher mean stresses. The stiffness and strength of 2D HOIPs are gradually weakened under subcritical loading, potentially as a result of stress‐induced defect nucleation and accumulation. The cyclic loading component can further accelerate this process. The fatigue lifetime of 2D HOIPs can be extended by reducing the mean stress, stress amplitude, or increasing the thickness. These results can provide indispensable insights into designing and engineering 2D HOIPs and other hybrid organic–inorganic materials for long‐term mechanical durability. [ABSTRACT FROM AUTHOR]

Traditional way to upgrade the stability and current efficiency performance of OLED device is seeking for new generation of electroluminescent materials. We provide a composite cavity design for longer lifetime, lower cost, and equivalent luminance by using the same materials. It consists of two first‐order red and green cavities and a second‐order blue cavity, which means different optical thickness of the RGB micro cavities. Due to the shorter distance between emitting molecules and metal electrodes, 1st order cavity obtains longer lifetime by surface plasmon coupling. A 52.7% improvement of calculated white lifetime can be accomplished with a respective 89.1% and 54.9% longer lifetime of red and green devices. 1/3 even more organic materials can be saved. Less angular luminance decay and lower working voltage are also demonstrated in the experimental part. [ABSTRACT FROM AUTHOR]

Metal phosphorus trichalcogenides (MPTCs) are emerging 2D semiconductor materials with unique functional properties that set them apart from other 2D systems. Despite the importance of their mechanical properties for improving the semiconductor device's durability and performance, as well as for utilizing strain effects to customize material properties and create new functionality, our current understanding of MPTCs' mechanical behavior is lacking and lags behind our knowledge of their other properties. Here, we use LiInP2Se6 as a model example of MPTCs and report the first experimental measurements of the elastic and plastic (fracture) properties along both in-plane and out-of-plane directions by atomic force microscopy and nanoindentation. Being a 2D material that is entirely inorganic, LiInP2Se6 surprisingly exhibits mechanical properties that resemble those of hybrid organic–inorganic materials rather than pure inorganic 2D materials. It has a soft crystal structure with low elastic moduli, a low difference in in-plane vs out-of-plane mechanical properties, and a combination of elastic and plastic characteristics of hybrid organic–inorganic materials. Our work provides the mechanical information critically needed to mitigate and/or harness the strain effects in LiInP2Se6-based semiconductor devices and sheds light on the mechanical behaviors of MPTCs with indispensable insights. [ABSTRACT FROM AUTHOR]

Ralstonia solanacearum is one of the ten most harmful plant bacteria worldwide, and traditional agrochemicals are not very effective in controlling this pathogen. Moreover, excessive pesticides always bring organic residues and resistant strains, which cause the unsustainability of the environment. In this paper, ferulic acid and essential oils are used as antibacterial materials. These compounds are natural substances with low toxicity and environmental safety. Through the structural optimization and the analysis of binary combined bacteriostatic efficiency, the MIC values of chlorobutyl ferulate (2e) and peppermint essential oil (EO1) were 0.64 mg/mL and 2.02 mg/mL, respectively, and the MIC value of 2e-EO1 (mass ratio 1:1.5) was 0.40 mg/mL. The growth rate of bacteria treated with 2e-EO1 was inhibited, the OD590nm value of cell membrane decreased by 57.83%, and the expression levels of hrpB, pehC, pilT, polA, aceE, egl, and phcA were downregulated to 18.81%, 30.50%, 14.00%, 44.90%, 86.79%, 23.90%, and 27.56%, respectively. The results showed that 2e-EO1 had a synergistic inhibitory effect against R. solanacearum. It significantly affected the formation of the bacterial cell membrane and the expression of pathogenic genes. Consequently, 2e-EO1 provides the potential to become a green pesticide and can promote the sustainability of the agricultural ecological environment. [ABSTRACT FROM AUTHOR]

Background: Mitochondrial DNA (mtDNA) is a potent activator for pro‐inflammatory response. Dendritic cells (DCs) are immunosuppressed in sepsis, whether mtDNA mediates immunoparalysis in sepsis remains unknown. Methods: The mRNAs were assessed by qPCR. Flow cytometry was used to measure the expression of costimulatory molecules and the proliferation of CD4+ T cells. Western blot and immunofluorescence staining were used to analyse the expression of proteins. Cytokine secretion was detected by ELISA. Histology of lung tissue was used to assess the inflammatory injury. Results: Lipopolysaccharide‐induced endotoxemia increased plasma mtDNA levels and immunoparalysis of spleen DCs, while hydrolysing mtDNA reversed immunoparalysis of spleen DCs in vivo. Moreover, cytoplasmic mtDNA of DCs was accumulated in endotoxemia and sepsis. mtDNA transfection into bone marrow‐derived DCs (BMDCs) inhibited the expression of costimulatory molecules (e.g., CD40, CD80 and CD86) and the release of IL‐12p70, while increasing the secretion of IL‐10. Cytoplasmic mtDNA also inhibited the ability of BMDCs to promote the proliferation of CD4+ T cells. Mechanistic analysis revealed that STING signalling was required for mtDNA‐mediated immunoparalysis of DCs in vivo and in vitro. Further studies showed deletion of STING reversed mtDNA‐mediated immunoparalysis of DCs and improved the prognosis of endotoxemia and sepsis. Conclusion: Our results demonstrated that mtDNA promotes immunoparalysis of DCs, and contributes to sepsis‐associated immunosuppression by activating STING signalling. Our study may provide new insights to elucidate the molecular pathogenesis of immunosuppressive DCs in sepsis. [ABSTRACT FROM AUTHOR]

Robots with submillimeter dimensions are of interest for applications that range from tools for minimally invasive surgical procedures in clinical medicine to vehicles for manipulating cells/tissues in biology research. The limited classes of structures and materials that can be used in such robots, however, create challenges in achieving desired performance parameters and modes of operation. Here, we introduce approaches in manufacturing and actuation that address these constraints to enable untethered, terrestrial robots with complex, three-dimensional (3D) geometries and heterogeneous material construction. The manufacturing procedure exploits controlled mechanical buckling to create 3D multimaterial structures in layouts that range from arrays of filaments and origami constructs to biomimetic configurations and others. A balance of forces associated with a one-way shape memory alloy and the elastic resilience of an encapsulating shell provides the basis for reversible deformations of these structures. Modes of locomotion and manipulation span from bending, twisting, and expansion upon global heating to linear/curvilinear crawling, walking, turning, and jumping upon laser-induced local thermal actuation. Photonic structures such as retroreflectors and colorimetric sensing materials support simple forms of wireless monitoring and localization. These collective advances in materials, manufacturing, actuation, and sensing add to a growing body of capabilities in this emerging field of technology. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of carbon dioxide (CO2) toward chemical and fuel production is a compelling component of the new energy system. Two‐dimensional bismuth with a particular surface has been identified as a highly efficient electrocatalyst for converting CO2 to formate. However, the development of a controllable synthetic strategy for possible large‐scale production of such Bi materials remains highly challenging. Herein, a scalable chemical interface confinement reduction method is proposed for topotactic transformation of BiOBr (001) nanosheets to metallic Bi (001) porous nanosheets (PNS). As expected, the Bi (001) PNS exhibits excellent electrochemical performance on CO2 reduction to formate, with Faradaic efficiency of 95.2% and formate partial current density of 72 mA cm−2. Density functional theory calculations suggest that Bi PNS selectively exposes (001) surfaces with small‐angle grain boundaries can significantly lower the free energy barrier for the formation of *OCHO, which are responsible for the high activity and selectivity toward CO2‐to‐formate conversion. [ABSTRACT FROM AUTHOR]

Purpose. Transcutaneous electrical acupoint stimulation (TEAS) is widely used. However, no study evaluated TEAS on systemic inflammatory response syndrome (SIRS) of patients after percutaneous nephrolithotomy (PCNL). The study was to evaluate TEAS on SIRS of patients after PCNL. Methods. 67 patients were enrolled and divided into group TEAS and group sham TEAS. Data were collected from 60 participants finally. In the study, TEAS or sham TEAS on bilateral Shenshu (BL23), Yinlingquan (SP9), Hegu (LI4), and Neiguan (PC6) was performed continuously throughout the procedure. The primary outcome included the incidence of systemic inflammatory response syndrome (SIRS) within 48 h after surgery. The secondary outcomes included the serum levels of inflammatory cytokines, hemodynamics changes, complications, and hospital stay after surgery. The serum levels of tumor necrosis factor- (TNF-) α and interleukin- (IL-) 6, mean arterial pressure (MAP), and heart rate (HR) at 30 min before anesthesia (T0), the time after surgery (T1), 24 h postoperation (T2), and 48 h postoperation (T3) were recorded. The consumption of analgesic during surgery was also recorded, as well as the complications and duration of hospital stay after PCNL. Results. The incidence of SIRS in group TEAS was lower than group sham TEAS (30% vs. 6.67%, p = 0.023). Compared with the sham TEAS group, both levels of TNF-α and IL-6 at T1, T2, and T3 were lower in the TEAS group (p < 0.05). The levels of MAP and HR in sham TEAS at T1, T2, and T3 were markedly higher than that in the TEAS group (p < 0.05). The total consumption of propofol and remifentanil during surgery in group TEAS was lower than that in the sham TEAS group. The incidence of hypotension, hypertension, emergence agitation, and postoperative nausea and vomiting (PONV) was also lower in group TEAS after PCNL (p < 0.05). Conclusions. TEAS could effectively reduce the incidence of SIRS and inflammatory cytokines for patients who underwent PCNL. In addition, TEAS helped to maintain the hemodynamic stability and cut down the consumption of analgesics during PCNL, reducing the complications after PCNL. [ABSTRACT FROM AUTHOR]

Fibrosis is a hallmark of aging tissues which often leads to altered architecture and function. The ovary is the first organ to show overt signs of aging, including increased fibrosis in the ovarian stroma. How this fibrosis affects ovarian biomechanics and the underlying mechanisms are unknown. Using instrumental indentation, we demonstrated a quantitative increase in ovarian stiffness, as evidenced by an increase in Young's modulus, when comparing ovaries from reproductively young (6–12 weeks) and old (14–17 months) mice. This ovarian stiffness was dependent on collagen because ex vivo enzyme‐mediated collagen depletion in ovaries from reproductively old mice restored their collagen content and biomechanical properties to those of young controls. In addition to collagen, we also investigated the role of hyaluronan (HA) in regulating ovarian stiffness. HA is an extracellular matrix glycosaminoglycan that maintains tissue homeostasis, and its loss can change the biomechanical properties of tissues. The total HA content in the ovarian stroma decreased with age, and this was associated with increased hyaluronidase (Hyal1) and decreased hyaluronan synthase (Has3) expression. These gene expression differences were not accompanied by changes in ovarian HA molecular mass distribution. Furthermore, ovaries from mice deficient in HAS3 were stiffer compared to age‐matched WT mice. Our results demonstrate that the ovary becomes stiffer with age and that both collagen and HA matrices are contributing mechanisms regulating ovarian biomechanics. Importantly, the age‐associated increase in collagen and decrease in HA are conserved in the human ovary and may impact follicle development and oocyte quality. [ABSTRACT FROM AUTHOR]

Patients undergoing cardiac valve replacement may experience cardiovascular adverse events during the preoperative period before anesthesia. The study was to compare the preemptive anti–stress response effects of oxycodone versus sufentanil for patients undergoing cardiac valve replacement. Ninety‐four patients were enrolled and assigned to group Oxy, group Suf and group NS. Patients in group Oxy were administrated with oxycodone 0.1 mg/kg, group Suf received sufentanil 0.1 μg/kg and group NS were given equivalent volume of normal saline. The primary outcomes included serum levels of cortisol, norepinephrine, and adrenaline. The secondary outcomes involved bispectral index value and the observer's assessment of awareness/sedation grade, levels of mean arterial pressure, heart rate, and the adverse reactions. Compared to group NS, the serum levels of cortisol at T1 to T5 (P <.05), and levels of norepinephrine and adrenaline at T3 to T5 (P <.05) in group Oxy and Suf were lower. The bispectral index value and observer's assessment of awareness/sedation grade T1 to T2 (P <.05) in group Suf were lower than those in group Oxy and NS. Compared with group NS, the levels of mean arterial pressure and heart rate in group Oxy and Suf at T3 to T5 (P <.05) were lower. The incidence of coughing was significantly higher in group Suf (23.3%), but not in group NS (6.7%), than that in group Oxy (3.3%). The preemptive analgesia of oxycodone may be used to inhibit the stress response, without leading to excessive sedation and respiratory depression, which may also help to stabilize hemodynamics during preoperative period. [ABSTRACT FROM AUTHOR]

Abstract Introduction Acupuncture is widely used as perioperative analgesia and promotes postoperative physical recovery. Transcutaneous electrical acupoint stimulation (TEAS) is a acupuncture method that has many advantages. However, there has been little study on the application of TEAS in laparoscopic radical gastrectomy. This is a study exploring the effects of TEAS on gastrointestinal function recovery after laparoscopic radical gastrectomy in order to provide a stimulation model for clinical use. Methods A total of 120 gastric cancer patients undergoing laparoscopic radical gastrectomy were randomly assigned into the long duration TEAS (L-TEAS) group, or the placebo-control (C-TEAS) group. All patients were routinely anesthetized. For the L-TEAS group TEAS was maintained from 30 min before anesthetic induction to 30 min after the operation, and TEAS was also performed for 30 min at 8 a.m., 1 p.m. and 6 p.m. within 2 d of the operation. But in the C-TEAS group, the output wires of the stimulator were broken. The stimulation sites included bilateral Zusanli (ST 36) and Neiguan (PC 6) acupoints. Postoperatively, the patients received patient-controlled intravenous analgesia (PCIA). The consumption of analgesics as well as the scores of the visual analogue scale (VAS) and Ramsay Sedation Scale (RSS) at 4 h (T1), 8 h (T2), 16 h (T3), 24 h (T4) and 36 h (T5) were observed and recorded after the operation in the 2 groups. The duration of first bowel sounds, flatus and defecation were recorded after the operation. The incidence of postoperative nausea and vomiting (PONV) as well as patient satisfaction was recorded. Results Compared to the C-TEAS group, the VAS scores at 4 h (2.79 ± 0.48 vs. 3.41 ± 0.62), 8 h (2.65 ± 0.42 vs. 3.17 ± 0.49), and 24 h (1.98 ± 0.39 vs. 2.72 ± 0.73) were significantly decreased in the L-TEAS group (P < 0.05) after the operation. Compared to the C-TEAS group, analgesic consumption at 4 h (10.02 ± 2.26 vs. 13.38 ± 2.98), 8 h (20.55 ± 4.59 vs. 24.63 ± 3.94) and 36 h (72.64 ± 9.74 vs. 76.01 ± 10.43) was significantly decreased in the L-TEAS group (P < 0.05) after the operation. There was a significant difference in the incidence of PONV between the L-TEAS (12%) and C-TEAS (32.2%) groups (P < 0.05). No significant difference was observed with respect to RSS among the 2 groups (P > 0.05). The time intervals from surgery to the first bowel sounds as well as the passage of flatus and defecation were shorter in the L-TEAS group than in the C-TEAS group (19.69 ± 7.61 h vs. 26.58 ± 7.43 h, 36.58 ± 10.75 h vs. 43.56 ± 9.57 h and 71.48 ± 20.62 h vs. 77.27 ± 22.67 h, respectively) (P < 0.05). The rate of moderately satisfaction and above in the L-TEAS (67.3%) group was higher than for that in the C-TEAS group (42.4%), and for very satisfied, the L-TEAS (55.2%) group was higher than that in the C-TEAS group (15.3%) (P < 0.05). Conclusions Preoperative TEAS and sustained TEAS within 2 d of the operation can effectively reduce the early postoperative pain, reduce the early postoperative consumption of analgesics, the total consumption of anesthetics, and the incidence of PONV as well as shorten the duration of first bowel sounds, first flatus and first defecation after the operation, promoting the recovery of gastrointestinal function and improving the patient satisfaction rate. [ABSTRACT FROM AUTHOR]

Candida albicans is a leading cause of catheter-associated urinary tract infections and elimination of these biofilm-based infections without antifungal agents would constitute a significant medical advance. A novel urinary catheter prototype that utilizes on-demand surface deformation is effective at eliminating bacterial biofilms and here the broader applicability of this prototype to remove fungal biofilms has been demonstrated. C. albicans biofilms were debonded from prototypes by selectively inflating four additional intralumens surrounding the main lumen of the catheters to provide the necessary surface strain to remove the adhered biofilm. Deformable catheters eliminated significantly more biofilm than the controls (>90% eliminated vs 10% control; p < 0.001). Mechanical testing revealed that fungal biofilms have an elastic modulus of 45 ± 6.7 kPa with a fracture energy of 0.4-2 J m−2. This study underscores the potential of mechanical disruption as a materials design strategy to combat fungal device-associated infections. [ABSTRACT FROM AUTHOR]