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Palladium hydrides (PdHx) are pivotal in both fundamental research and practical applications across a wide spectrum. PdHx nanocrystals, synthesized by heating in dimethylformamide (DMF), exhibit remarkable stability, granting them widespread applications in the field of electrocatalysis. However, this stability appears inconsistent with their metastable nature. The substantial challenges in characterizing nanoscale structures contribute to the limited understanding of this anomalous phenomenon. Here, through a series of well-conceived experimental designs and advanced characterization techniques, including aberration-corrected scanning transmission electron microscopy (AC-STEM), in situ X-ray diffraction (XRD), and time-of-flight secondary ion mass spectrometry (TOF-SIMS), we have uncovered evidence that indicates the presence of C and N within the lattice of Pd (PdCxNy), rather than H (PdHx). By combining theoretical calculations, we have thoroughly studied the potential configurations and thermodynamic stability of PdCxNy, demonstrating a 2.5:1 ratio of C to N infiltration into the Pd lattice. Furthermore, we successfully modulated the electronic structure of Pd nanocrystals through C and N doping, enhancing their catalytic activity in methanol oxidation reactions. This breakthrough provides a new perspective on the structure and composition of Pd-based nanocrystals infused with light elements, paving the way for the development of advanced catalytic materials in the future.
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Though Sn-Pb alloyed perovskite solar cells (PSCs) achieved great progress, there is a dilemma to further increase Sn for less-Pb requirement. High Sn ratio (>70%) perovskite exhibits nonstoichiometric Sn:Pb:I at film surface to aggravate Sn2+ oxidation and interface energy mismatch. Here, ternary metal alloyed (FASnI3 )0.7 (MAPb1- x Znx I3 )0.3 (x = 0-3%) is constructed for Pb% < 30% perovskite. Zn with smaller ionic size and stronger ionic interaction than Sn/Pb assists forming high-quality perovskite film with ZnI6 4- enriched at surface to balance Sn:Pb:I ratio. Differing from uniform bulk doping, surface-rich Zn with lower lying orbits pushes down the energy band of perovskite and adjusts the interface energy for efficient charge transfer. The alloyed PSC realizes efficiency of 19.4% at AM1.5 (one of the highest values reported for Pb% < 30% PSCs). Moreover, stronger bonding of ZnâI and SnâI contributes to better durability of ternary perovskite than binary perovskite. This work highlights a novel alloy method for efficient and stable less-Pb PSCs.
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Nanocrystals (NCs) exposed with high-index facets usually show enhanced electrocatalytic performances. However, it is a great challenge to persevere with high-index facets against their high surface energy during the synthesis. Herein, we successfully synthesize concave hexoctahedral (c-HOH) Pd NCs exposed with 48 high-index {741} facets using a facile one-pot wet-chemical protocol. Control experiments illustrate that l-ascorbic acid plays a critical role in the formation of the c-HOH morphology, acting as both reducing and capping agents. Moreover, we can extend the synthesis for fabricating c-HOH Pd@Pt core-shell NCs by simply introducing a Pt precursor into the reaction solution, attaining remarkably boosted electrocatalysis for methanol electrooxidation reaction (MOR). Integrating the merits of {741} facets, concave structure, and ligand and strain effect of the core-shell structure, c-HOH Pd4@Pt1 core-shell NCs showed an excellent MOR mass activity of 1.18 A mgPGM-1 or 3.60 A mgPt-1, which is 3.80 or 11.61 times higher than that of commercial Pt/C, respectively.
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Traditional eye drops are administered via topical instillation. However, frequent dosing is needed due to their relatively rapid precorneal removal and low ocular bioavailability. To address these issues, stearoyl L-carnitine-modified nanoemulsions (SC-NEs) were fabricated. The physicochemical properties of SC-NEs in terms of size, morphology, zeta potential, encapsulation efficiency, and in vitro drug release behavior were characterized. The cellular uptake and mechanisms of SC-NEs were comprehensively studied in human corneal epithelial cells and the stearoyl L-carnitine ratio in SC-NEs was optimized. The optimized SC-NEs could target the novel organic cation/carnitine transporter 2 (OCTN2) and amino acid transporter B (0 +) (ATB0,+) on the corneal epithelium, which led to superior corneal permeation, ocular surface retention ability, ocular bioavailability. Furthermore, SC-NEs showed excellent in vivo anti-inflammatory efficacy in a rabbit model of endotoxin-induced uveitis. The ocular safety test indicated that the SC-NEs were biocompatible. In general, the current study demonstrated that OCTN2 and ATB0,+-targeted nanoemulsions were promising ophthalmologic drug delivery systems that can improve ocular drug bioavailability and boost the therapeutic effects of drugs for eye diseases.
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Sistemas de Liberación de Medicamentos , Células Epiteliales , Animales , Humanos , Conejos , Miembro 5 de la Familia 22 de Transportadores de Solutos/metabolismo , Transporte Biológico , Células Epiteliales/metabolismo , Carnitina/metabolismo , Carnitina/farmacologíaRESUMEN
To achieve large-scale development of triboelectric nanogenerators (TENGs) for water wave energy harvesting and powering the colossal sensors widely distributed in the ocean, facile and scalable TENGs with high output are urgently required. Here, an elastic self-recovering hybrid nanogenerator (ES-HNG) is proposed for water wave energy harvesting and marine environmental monitoring. The elastic skeletal support of the ES-HNG is manufactured using three-dimensional (3D) printing technology, which is more conducive to the large-scale integration of the ES-HNG. Moreover, the combination of a TENG and an electromagnetic generator (EMG) optimizes the utilization of device space, leading to enhanced energy harvesting efficiency. Experimental results demonstrate that the TENG achieves a peak power output of 42.68 mW, and the EMG reaches a peak power output of 4.40 mW. Furthermore, various marine environment monitoring sensors, such as a self-powered wireless meteorological monitoring system, a wireless alarm system, and a water quality monitoring pen, have been successfully powered by the sophisticated ES-HNG. This work introduces an ES-HNG for water wave energy harvesting, which demonstrates potential in marine environment monitoring and offers a new solution for the sustainable development of the marine internet of things.
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Recently, narrow bandgap tin-lead mixed perovskite solar cells (PSCs) have become a research hotspot because they can be applied in tandem cells to break the Shockley-Queisser radiative limit of the single junction PSCs. However, the introduction of tin, on the one hand, makes the crystal quality of perovskite thin film worse, leading to the increase of film defects; on the other hand, the easy oxidation of divalent tin also leads to the increase of defect states, which seriously affects the photoelectric conversion efficiency of tin-lead cell devices. Good crystallization and low defect density of perovskite layer are very important to ensure good light absorption and photogenerated carrier generation and transport. Here, we adjust the crystallization of tin-lead perovskite films by a Lewis base-urea (CO(NH2)2), which significantly increases the grain size and improves the film morphology. At the same time, because of the Lewis base property of urea, the uncoordinated Pb2+and Sn2+defects of Lewis acids in the tin-lead films are effectively passivated, and the occurrence of non-radiative recombination in the films is reduced. Under the dual effects of improving crystallization and passivating defects, the photoelectric performance of tin-lead perovskite solar cell devices is significantly improved to 18.1% compared with the original device of 15.4%.
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Breaking atomic monogeneity of catalyst surfaces is promising for constructing synergistic active centers to cope with complex multi-step catalytic reactions. Here, we report a defect-derived strategy for creating surface phosphorous vacancies (P-vacancies) on nanometric Rh2 P electrocatalysts toward drastically boosted electrocatalysis for alkaline hydrogen oxidation reaction (HOR). This strategy disrupts the monogeneity and atomic regularity of the thermodynamically stable P-terminated surfaces. Density functional theory calculations initially verify that the competitive adsorption behavior of Had and OHad on perfect P-terminated Rh2 P{200} facets (p-Rh2 P) can be bypassed on defective Rh2 P{200} surfaces (d-Rh2 P). The P-vacancies enable the exposure of sub-surface Rh atoms to act as exclusive H adsorption sites. Therein, the Had cooperates with the OHad on the peripheral P-sites to effectively accelerate the alkaline HOR. Defective Rh2 P nanowires (d-Rh2 P NWs) and perfect Rh2 P nanocubes (p-Rh2 P NCs) are then elaborately synthesized to experimentally represent the d-Rh2 P and p-Rh2 P catalytic surfaces. As expected, the P-vacancy-enriched d-Rh2 P NWs catalyst exhibits extremely high catalytic activity and outstanding CO tolerance for alkaline HOR electrocatalysis, attaining 5.7 and 14.3â times mass activity that of p-Rh2 P NCs and commercial Pt/C, respectively. This work sheds light on breaking the surface atomic monogeneity for the development of efficient heterogeneous catalysts.
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Antigen-escape relapse has emerged as a major challenge for long-term disease control after CD19-directed therapies, to which dual-targeting of CD19 and CD22 has been proposed as a potential solution. From March 2016 through January 2018, we conducted a pilot study in 89 patients who had refractory/relapsed B-cell malignancies, to evaluate the efficacy and safety of sequential infusion of anti-CD19 and anti-CD22, a cocktail of 2 single-specific, third-generation chimeric antigen receptor-engineered (CAR19/22) T cells. Among the 51 patients with acute lymphoblastic leukemia, the minimal residual disease-negative response rate was 96.0% (95% confidence interval [CI], 86.3-99.5). With a median follow-up of 16.7 months (range, 1.3-33.3), the median progression-free survival (PFS) was 13.6 months (95% CI, 6.5 to not reached [NR]), and the median overall survival (OS) was 31.0 months (95% CI, 10.6-NR). Among the 38 patients with non-Hodgkin lymphoma, the overall response rate was 72.2% (95% CI, 54.8-85.8), with a complete response rate of 50.0% (95% CI, 32.9-67.1). With a median follow-up of 14.4 months (range, 0.4-27.4), the median PFS was 9.9 months (95% CI, 3.3-NR), and the median OS was 18.0 months (95% CI, 6.1-NR). Antigen-loss relapse occurred in 1 patient during follow-up. High-grade cytokine release syndrome and neurotoxicity occurred in 22.4% and 1.12% patients, respectively. In all except 1, these effects were reversible. Our results indicated that sequential infusion of CAR19/22 T cell was safe and efficacious and may have reduced the rate of antigen-escape relapse in B-cell malignancies. This trial was registered at www.chictr.org.cn as #ChiCTR-OPN-16008526.
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Antígenos CD19/inmunología , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Resistencia a Antineoplásicos , Recurrencia Local de Neoplasia/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/terapia , Receptores de Antígenos de Linfocitos T/inmunología , Lectina 2 Similar a Ig de Unión al Ácido Siálico/inmunología , Adolescente , Adulto , Anciano , Niño , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/inmunología , Recurrencia Local de Neoplasia/patología , Proyectos Piloto , Leucemia-Linfoma Linfoblástico de Células Precursoras B/inmunología , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patología , Pronóstico , Terapia Recuperativa , Tasa de Supervivencia , Linfocitos T/inmunología , Adulto JovenRESUMEN
BACKGROUND: Mental health has become a global problem, among which anxiety and depression disorder were ranked as the first and sixth leading causes of disability, respectively, according to the World Health Organization (WHO). Medical students experienced higher levels of anxiety and depression than the general population. But there was a lack of research on the emotional situation among medical students in Inner Mongolia. The main objectives of this study were to investigate the prevalence of anxiety and depression symptoms as well as the factors that influence them among medical students in Inner Mongolia. METHODS: A cross-sectional study was conducted on 1282 students from a university in Inner Mongolia, China, ranging in age from 16 to 27 years. They were assessed demographic indicators, the disorder of anxiety and depression using Zung's Self-Rating Anxiety Scale and Self-Rating Depression Scale (SAS and SDS) by an anonymous, self-administered questionnaire. The internal reliability and validity of the questionnaire were determined using Cronbach's alpha coefficient, Kaiser-Meyer-Olkin (KMO), and Bartlett's sphericity. T-tests and one-way ANOVA were used to explore factors, including demographic and behavioral information influencing anxiety and depression disorder. According to the above results of exploring the influencing factors based on univariate analysis, significant factors (p < 0.05) were entered into multiple linear regressions that sequentially fitted to predictors associated with anxiety and depression. The collected data were entered into EpiData for windows and analyzed using SPSS 26.0. The p < 0.05 was considered to be significantly different. RESULTS: The questionnaire was completed by 1187 students with a 92.59% response rate. The prevalence of anxiety and depression symptoms among medical students were 10.36% and 24.43%, and the mean ± standard deviation (M ± SD) anxiety and depression scores were 39.60 ± 7.81 and 48.23 ± 9.06, respectively, among the medical students. The specific contributions of the two scales with good reliability and validity were 60.58% and 63.59%, respectively. For univariate analysis, age, whether the daily meal was at a fixed time, grade, the birthplace of students, average daily eating habits, were the factors that influenced both the total score of SAS and SDS (p < 0.05). For further analysis, the results showed that "Birthplace of students" and "Whether daily meals at a fixed time" were significantly associated with anxiety and depression. Furthermore, "Age" and "Mode of delivery" were independent risk factors for depressive disorder. CONCLUSION: Our findings revealed that high prevalence of mental health problems among medical students in Inner Mongolia. The Ministry of Medical Education should make a targeted intervention for specific risk factors of this study to improve psychological well-being and face uncertain future challenges among university students in Inner Mongolia.
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Estudiantes de Medicina , Humanos , Adolescente , Adulto Joven , Adulto , Estudios Transversales , Estudiantes de Medicina/psicología , Depresión/epidemiología , Depresión/diagnóstico , Reproducibilidad de los Resultados , Ansiedad/epidemiología , Ansiedad/diagnóstico , Encuestas y Cuestionarios , Prevalencia , China/epidemiologíaRESUMEN
Direct epoxidation of propylene by molecular oxygen alone is one of the "dream reactions" in heterogeneous catalysis. Despite much effort, the yield of propylene epoxide is still too low to be commercially attractive due to the trade-off between conversion and selectivity. Here, we demonstrate that doping Cl into the lattice of Cu2O nanocrystals by the intergrowth method not only can enhance the catalytic selectivity and conversion of direct propylene epoxidation but also can solve the long-existing Cl loss problem. In particular, Cl-doped rhombic dodecahedral Cu2O with (110) exposing facets exhibited 63% PO selectivity with a 12.0 h-1 turnover frequency at 200 °C, outperforming any other coinage metal-based catalysts under mild conditions. Comprehensive characterization and theoretical calculations revealed that the Cl-decorated Cu(I) facilitated formation of electrophilic oxygen species, thus boosting the production of propylene oxide. This work provides a general strategy to develop catalysts and explore the promoter effect by creating uniform isolated anion doping to activate a nearby metal center by virtue of well-defined nanocrystals.
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BACKGROUND: In the postoperative period, patients mainly rely on caregivers, who experience their own physical and mental fatigue. Caregiver fatigue may affect patient outcomes. OBJECTIVES: This study explored the fatigue status and influencing factors of primary caregivers of patients after liver cancer surgery. METHODS: A baseline information questionnaire, the Fatigue Scale-14, and the Barthel Index were used to investigate the self-care ability and fatigue status of 191 primary caregivers of patients with hepatic carcinoma who had had surgery. FINDINGS: The postoperative hospitalization time and self-care level of patients, whether the primary caregiver had health insurance, subjective feelings of fatigue, the perception that health was affected, and the patients' desired level of postoperative care were correlated with the occurrence of primary caregiver fatigue.
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Cuidadores , Fatiga , Neoplasias Hepáticas , Autocuidado , Humanos , Masculino , Femenino , Persona de Mediana Edad , China , Cuidadores/psicología , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/enfermería , Adulto , Encuestas y Cuestionarios , Anciano , Periodo PosoperatorioRESUMEN
The poor film stability of Sn-Pb mixed perovskite film and the mismatched interface energy levels pose significant challenges in enhancing the efficiency of tin-lead (Sn-Pb) mixed perovskite solar cells. In this study, polyvinylpyrrolidone (PVP) is introduced into the PVK perovskite precursor solution, effectively enhancing the overall stability of the film. This improvement is achieved through the formation of robust coordination bonds between the carbonyl (C=O) in the pyrrole ring and the undercoordinated SnII and PbII, thereby facilitating the passivation of defects. Furthermore, the introduction of PVP inhibits the oxidation of tin (Sn), thereby enhancing the n-type characteristics of the perovskite film. This adjustment in the energy level of the PVK perovskite film proves instrumental in reducing interface energy loss, subsequently improving interface charge transfer and mitigating device recombination. Consequently, perovskite solar cells incorporating PVP achieve an outstanding champion power conversion efficiency (PCE) of 21.31%.
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OBJECTIVE: To investigate the value of immunoglobulin heavy chain (IgH) gene rearrangement in monitoring minimal residual disease (MRD) in multiple myeloma (MM) received autologous hematopoietic stem cell transplantation(auto-HSCT). METHODS: The clinical data of 26 MM patients who received auto-HSCT in the Department of Hematology, Wuhan First Hospital from 2018 to 2022 were collected. IgH rearrangement was detected by multiplex PCR combined with capillary electrophoresis fragment analysis to evaluate minimal residual disease (MRD), and the outcome of the disease was analyzed statistically. RESULTS: Among the 26 MM patients, 18 were males and 8 were females, with a median age of 59(41-70) years. The median follow-up time after transplantation was 33 (7-52) months. Compared with the IgH rearrangement negative group (n=17), the proportion of CR and sCR of patients with IgH rearrangement positive in bone marrow samples before auto-HSCT at 3 months after transplantation was lower ï¼1/9 vs 14/17ï¼, and the duration of remission (DOR) after transplantation was shorterï¼10.78±4.35 vs 15.88±5.22 monthsï¼, with statistically significant difference in DOR between the two groups(P < 0.05). Compared with IgH rearrangement negative group (n=21), the proportion of CR and sCR of patients with positive IgH rearrangement results from peripheral blood stem cell collection at 3 months after transplantation was lowerï¼0/5 vs 15/21ï¼, the duration of remission (DOR) after transplantation was shorterï¼9.60±4.83 vs 15.19±5.11 monthsï¼, and the difference in DOR between the two groups was statistically significant (P < 0.05). During the follow-up period, 5 patients (5/9) with positive IgH rearrangement results in bone marrow specimens died, and all patients with negative IgH rearrangement results survived. Four patients (4/5) with positive IgH rearrangement results by peripheral blood stem cell samples died, while one patient (1/21) with negative IgH rearrangement results died. In both bone marrow and peripheral blood stem cell samples, the survival time of IgH rearrangement-positive patients after transplantation was shorter than that of IgH rearrangement-negative patients(P < 0.05). Logistic regression analysis showed that gender, disease stage, the proportion of bone marrow smear plasma cells at initial diagnosis, stem cell mobilization plan, efficacy evaluation before transplantation (≥CR and
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Trasplante de Células Madre Hematopoyéticas , Mieloma Múltiple , Masculino , Femenino , Humanos , Persona de Mediana Edad , Anciano , Mieloma Múltiple/genética , Mieloma Múltiple/terapia , Neoplasia Residual/diagnóstico , Trasplante Autólogo , Reordenamiento GénicoRESUMEN
The state-of-the-art triboelectric nanogenerator (TENG) technology has numerous advantages and creates new prospects for the rapid development of the Internet of Things (IoT) in marine environments. Here, to accelerate the application process of TENG, an elaborately designed multilayered sleeve-structured hybrid nanogenerator (M-HNG) is developed to efficiently and persistently harvest marine energy. The M-HNG integrates an electromagnetic nanogenerator (EMG) with four coils and a multilayered sleeve-structured TENG (MS-TENG) with three freestanding layer units to increase spatial utilization efficiency. Moreover, rabbit fur strips are introduced to enhance the output performance and strengthen the durability of TENG. Therefore, the MS-TENG has high durability due to its soft-contact structure, maintaining its performance even after 240,000 cycles. When a 1000 µF capacitor is charged by M-HNG utilizing a power management circuit (PMC), the stored energy is increased from 2.62 mJ to 140.11 mJ, representing a significant improvement of 52-fold. The M-HNG triggered by water waves has successfully powered various small electronic devices, including 1200 LED lights, nine thermo-hygrometers, a water quality testing pen, and water level alarms. The proposed M-HNG effectively harvests low-frequency water wave energy, introducing an innovative concept for constructing a hybrid TENG with enhanced density and durability.
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The influence of salt consumption on physiological processes, especially blood pressure (BP), metabolism, and cognition, remains a topical concern. While guidelines endorse reduced salt diets, there are gaps in understanding the age-specific implications and challenges in adherence. The present study delved into the differential effects of salt intake on young adult and aged male rats over a 12-week period, using control, low-, and high-salt diets. Key metrics, such as BP, cognition, and general parameters, were monitored. Our findings revealed significant age-dependent effects of salt intake on survival rates, body weight, blood sodium, blood glucose, blood lipids, BP, heart rates, and cognition. Notably, young adult rats did not show significant sodium level changes on a high-salt diet, whereas aged rats experienced increased sodium levels even on a normal salt diet. Blood glucose levels decreased significantly in aged rats on a high-salt diet but remained stable in young adults. Aged rats had the highest survival rates on low-salt diets. Low-salt diets led to reduced BP in both age groups, more significantly in young adults. Young adult rats displayed increased BP variability on both high- and low-salt diets, while a decrease in BP variability was exclusive to aged rats on a low-salt diet. There were significant differences across age groups in short-term memory, but not in long-term memory. The study provides a nuanced understanding of the age-dependent physiological effects of salt intake, suggesting the necessity of age-specific guidelines for public health.
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Hipertensión , Cloruro de Sodio Dietético , Ratas , Masculino , Animales , Presión Sanguínea , Dieta Hiposódica , Cloruro de Sodio , Sodio , CogniciónRESUMEN
Tin-lead (Sn-Pb) mixed perovskite with a narrow bandgap is an ideal candidate for single-junction solar cells approaching the Shockley-Queisser limit. However, due to the easy oxidation of Sn2+, the efficiency and stability of Sn-Pb mixed perovskite solar cells (PSCs) still lag far behind that of Pb-based solar cells. Herein, highly efficient and stable FA0.5MA0.5Pb0.5Sn0.5I0.47Br0.03 compositional PSCs are achieved by introducing an appropriate amount of multifunctional Tin (II) oxalate (SnC2O4). SnC2O4 with compensative Sn2+ and reductive oxalate group C2O4 2- effectively passivates the cation and anion defects simultaneously, thereby leading to more n-type perovskite films. Benefitting from the energy level alignment and the suppression of bulk nonradiative recombination, the Sn-Pb mixed perovskite solar cell treated with SnC2O4 achieves a power conversion efficiency of 21.43%. More importantly, chemically reductive C2O4 2- effectively suppresses the notorious oxidation of Sn2+, leading to significant enhancement in stability. Particularly, it dramatically improves light stability.
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Air-processed perovskite solar cells (PSCs) with high photoelectric conversion efficiency (PCE) can not only further reduce the production cost but also promote its industrialization. During the preparation of the PSCs in ambient air, the contact of the buried interface not only affects the crystallization of the perovskite film but also affects the interface carrier transport, which is directly related to the performance of the device. Here, we optimize the buried interface by introducing 3-mercaptopropyltrimethoxysilane (MPTMS, (CH3O)3Si(CH2)3SH) on the nickel oxide (NiOx) surface. The crystallization of the perovskite film is improved by enhancing surface hydrophobicity; besides, the SH-based functional group of MPTMS passivates the uncoordinated lead at the interface, which effectively reduces the defects at the bottom interface of perovskite and inhibits the nonradiative recombination at the interface. Moreover, the energy level between the NiOx layer and the perovskite layer is better matched. Based on multiple functions of MPTMS modification, the open circuit voltage of the device is obviously improved, and efficient air-processed methylamine-free (MA-free) PSCs are realized with PCE reaching 21.0%. The device still maintains the initial PCE of 85% after 1000 h aging in the glovebox. This work highlights interface modification in air-processed MA-free PSCs to promote the industrialization of PSCs.
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The activity-stability trade-off relationship of oxygen reduction reaction (ORR) is a tricky issue that strikes the electrocatalyst population and hinders the widespread application of fuel cells. Here neoteric biphase Pd nanosheets that are structured with ultrathin two-dimensional crystalline Pd inner cores and ≈1 nm thin atomic-hybrid RhOx/Pd amorphous skins, named c/a-Pd@PdRh NSs, for disentangling this trade-off dilemma for alkaline ORR are developed. The superthin amorphous skins significantly amplify the quantity of flexibly low-coordinated atoms for electrocatalysis. An in situ selected oxidation of the top-surface Rh dopants creates atomically hybrid RhOx/Pd disorder surfaces. Detailed energy spectra and theoretical simulation confirm that these RhOx/Pd interfaces can arouse a surface charge redistribution, causing significant electron deficiency and lowered d-band center for surface Pd. Meanwhile, anticorrosive Rh/RhOx species can thermodynamically passivate the neighboring Pd atoms from oxidative dissolution. Thanks to these amplified interfacial effects, the biphase c/a-Pd@PdRh NSs simultaneously exhibit a superhigh ORR activity (5.92 A mg-1, 22.8 times that of Pt/C) and an outstanding long-lasting stability after 100k cycles of accelerated durability test, showcasing unprecedented electrocatalysts for breaking the activity-stability trade-off relationship of ORR. This work paves a bran-new strategy for designing high-performance electrocatalysts through creating modulated amorphous skins on low-dimensional nanomaterials.
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OBJECTIVES: Polyphenol compounds are classified as organic compounds with phenolic units exhibiting a variety of biological functions. This meta-analysis aims to assess the efficacy and safety of polyphenol compounds (curcumin, cranberry, garlic, liquorice and broccoli) in eradicating Helicobacter pylori. DESIGN: Systematic review and meta-analysis. METHODS: Literature searches were conducted on PubMed, Embase, The Cochrane Library, Web of Science, Medline, Chinese National Knowledge Infrastructure database, Chinese Scientific Journal Database and Wan Fang database from inception to January 2022. All randomised controlled trials comparing polyphenol compounds with the placebo or used as an adjunct treatment are included in this meta-analysis.The treatment effect for dichotomous outcomes was assessed using risk ratio (RR), while for continuous outcomes, mean differences both with 95% CIs, were used. Subgroup analyses were carried out for different treatment schemes and polyphenol compound species. RESULTS: 12 trials were included in the meta-analysis. The total eradication rate of H.pylori in the polyphenol compounds group was higher than in the group without polyphenol compounds. Statistical significance was also observed (RR 1.19, 95% CI 1.03 to 1.38, p=0.02). The most frequent adverse effects of polyphenol compounds included diarrhoea, headache and vomiting. However, there were no differences regarding side effects between the two groups (RR 1.47, 95% CI 0.83 to 2.58, p=0.18). In subgroup analyses, the H.pylori eradication rate regimens with polyphenols therapy was superior to that of regimens without polyphenols therapy in the polyphenols versus placebo subgroup (RR 4.23, 95% CI 1.38 to 12.95, p=0.01), polyphenols plus triple therapy versus triple therapy subgroup (RR 1.11, 95% CI 1.01 to 1.22, p=0.03). CONCLUSION: Polyphenol compounds can improve H.pylori eradication rates. Polyphenol compounds plus standard triple therapy can significantly improve the eradication. However, no evidence of a higher incidence of side effects could be found. PROSPERO REGISTRATION NUMBER: CRD42022307477.
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Infecciones por Helicobacter , Helicobacter pylori , Humanos , Antibacterianos/uso terapéutico , Infecciones por Helicobacter/tratamiento farmacológico , Polifenoles/farmacología , Polifenoles/uso terapéutico , Amoxicilina/uso terapéutico , Quimioterapia CombinadaRESUMEN
Developing facile synthetic strategies toward ultrafine one-dimensional (1D) nanowires (NWs) with rich catalytic hot spots is pivotal for exploring effective heterogeneous catalysts. Herein, we demonstrate a two-dimensional (2D) template-directed strategy for synthesizing 1D kink-rich Pd3Pb NWs with abundant grain boundaries to serve as high-efficiency electrocatalysts toward oxygen reduction reaction (ORR). In this one-pot synthesis, ultrathin Pd nanosheets were initially generated, which then served as self-sacrificial 2D nano-templates. A dynamic equilibrium growth was subsequently established on the 2D Pd nanosheets through the center-selected etching of Pd atoms and edge-preferred co-deposition of Pd/Pb atoms. This was followed by the oriented attachment of the generated Pd/Pb alloy nanograins and fragments. Thus, kink-rich Pd3Pb NWs with rich grain boundary defects were obtained in high yield, and these NWs were used as electrocatalytic active catalysts. The surface electronic interaction between Pd and Pb atoms effectively decreased the surface d-band center to weaken the binding of oxygen-containing intermediates toward improved ORR kinetics. Specifically, the kink-rich Pd3Pb NWs/C catalyst delivered outstanding ORR mass activity and specific activity (2.26 Aâ mgPd-1 and 2.59 mAâ cm-2, respectively) in an alkaline solution. These values were respectively 13.3 and 10.8 times those of state-of-the-art commercial Pt/C catalyst. This study provides an innovative strategy for fabricating defect-rich low-dimensional nanocatalysts for efficient energy conversion catalysis.