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1.
PLoS One ; 19(5): e0303420, 2024.
Article in English | MEDLINE | ID: mdl-38739625

ABSTRACT

INTRODUCTION: Studies indicate that individuals with chronic conditions and specific baseline characteristics may not mount a robust humoral antibody response to SARS-CoV-2 vaccines. In this paper, we used data from the Texas Coronavirus Antibody REsponse Survey (Texas CARES), a longitudinal state-wide seroprevalence program that has enrolled more than 90,000 participants, to evaluate the role of chronic diseases as the potential risk factors of non-response to SARS-CoV-2 vaccines in a large epidemiologic cohort. METHODS: A participant needed to complete an online survey and a blood draw to test for SARS-CoV-2 circulating plasma antibodies at four-time points spaced at least three months apart. Chronic disease predictors of vaccine non-response are evaluated using logistic regression with non-response as the outcome and each chronic disease + age as the predictors. RESULTS: As of April 24, 2023, 18,240 participants met the inclusion criteria; 0.58% (N = 105) of these are non-responders. Adjusting for age, our results show that participants with self-reported immunocompromised status, kidney disease, cancer, and "other" non-specified comorbidity were 15.43, 5.11, 2.59, and 3.13 times more likely to fail to mount a complete response to a vaccine, respectively. Furthermore, having two or more chronic diseases doubled the prevalence of non-response. CONCLUSION: Consistent with smaller targeted studies, a large epidemiologic cohort bears the same conclusion and demonstrates immunocompromised, cancer, kidney disease, and the number of diseases are associated with vaccine non-response. This study suggests that those individuals, with chronic diseases with the potential to affect their immune system response, may need increased doses or repeated doses of COVID-19 vaccines to develop a protective antibody level.


Subject(s)
Antibodies, Viral , COVID-19 Vaccines , COVID-19 , SARS-CoV-2 , Humans , Male , Female , COVID-19 Vaccines/immunology , COVID-19 Vaccines/administration & dosage , Middle Aged , COVID-19/prevention & control , COVID-19/epidemiology , COVID-19/immunology , Adult , SARS-CoV-2/immunology , Antibodies, Viral/blood , Antibodies, Viral/immunology , Aged , Texas/epidemiology , Chronic Disease , Seroepidemiologic Studies , Young Adult , Risk Factors
2.
Sci Adv ; 10(16): eadl1856, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38640241

ABSTRACT

Continuous glucose monitoring systems (CGMs) are critical toward closed-loop diabetes management. The field's progress urges next-generation CGMs with enhanced antinoise ability, reliability, and wearability. Here, we propose a coin-sized, fully integrated, and wearable CGM, achieved by holistically synergizing state-of-the-art interdisciplinary technologies of biosensors, minimally invasive tools, and hydrogels. The proposed CGM consists of three major parts: (i) an emerging biochemical signal amplifier, the organic electrochemical transistor (OECT), improving the signal-to-noise ratio (SNR) beyond traditional electrochemical sensors; (ii) a microneedle array to facilitate subcutaneous glucose sampling with minimized pain; and (iii) a soft hydrogel to stabilize the skin-device interface. Compared to conventional CGMs, the OECT-CGM offers a high antinoise ability, tunable sensitivity and resolution, and comfort wearability, enabling personalized glucose sensing for future precision diabetes health care. Last, we discuss how OECT technology can help push the limit of detection of current wearable electrochemical biosensors, especially when operating in complicated conditions.


Subject(s)
Biosensing Techniques , Diabetes Mellitus , Humans , Blood Glucose Self-Monitoring , Blood Glucose , Continuous Glucose Monitoring , Reproducibility of Results , Glucose , Diabetes Mellitus/diagnosis
3.
Adv Mater ; : e2402445, 2024 Apr 07.
Article in English | MEDLINE | ID: mdl-38583077

ABSTRACT

Brain disorders represent a significant challenge in medical science due to the formidable blood-brain barrier (BBB), which severely limits the penetration of conventional therapeutics, hindering effective treatment strategies. This review delves into the innovative realm of biomimetic nanodelivery systems, including stem cell-derived nanoghosts, tumor cell membrane-coated nanoparticles, and erythrocyte membrane-based carriers, highlighting their potential to circumvent the BBB's restrictions. By mimicking native cell properties, these nanocarriers emerge as a promising solution for enhancing drug delivery to the brain, offering a strategic advantage in overcoming the barrier's selective permeability. The unique benefits of leveraging cell membranes from various sources is evaluated and advanced technologies for fabricating cell membrane-encapsulated nanoparticles capable of masquerading as endogenous cells are examined. This enables the targeted delivery of a broad spectrum of therapeutic agents, ranging from small molecule drugs to proteins, thereby providing an innovative approach to neurocare. Further, the review contrasts the capabilities and limitations of these biomimetic nanocarriers with traditional delivery methods, underlining their potential to enable targeted, sustained, and minimally invasive treatment modalities. This review is concluded with a perspective on the clinical translation of these biomimetic systems, underscoring their transformative impact on the therapeutic landscape for intractable brain diseases.

4.
Front Oncol ; 14: 1283252, 2024.
Article in English | MEDLINE | ID: mdl-38559557

ABSTRACT

Background: Older cancer survivors likely experience physical function limitations due to cancer and its treatments, leading to disability and early mortality. Existing studies have focused on factors associated with surgical complications and mortality risk rather than factors associated with the development of poor disability status (DS), a proxy measure of poor performance status, in cancer survivors. We aimed to identify factors associated with the development of poor DS among older survivors of colorectal cancer (CRC) and compare poor DS rates to an age-sex-matched, non-cancer cohort. Methods: This retrospective cohort study utilized administrative data from the Texas Cancer Registry Medicare-linked database. The study cohort consisted of 13,229 survivors of CRC diagnosed between 2005 and 2013 and an age-sex-matched, non-cancer cohort of 13,225 beneficiaries. The primary outcome was poor DS, determined by Davidoff's method, using predictors from 12 months of Medicare claims after cancer diagnosis. Multivariable Cox proportional hazards regression was used to identify risk factors associated with the development of poor DS. Results: Among the survivors of CRC, 97% were 65 years or older. After a 9-year follow-up, 54% of survivors of CRC developed poor DS. Significant factors associated with future poor DS included: age at diagnosis (hazard ratio [HR] = 3.50 for >80 years old), female sex (HR = 1.50), race/ethnicity (HR = 1.34 for Hispanic and 1.21 for Black), stage at diagnosis (HR = 2.26 for distant metastasis), comorbidity index (HR = 2.18 for >1), and radiation therapy (HR = 1.21). Having cancer (HR = 1.07) was significantly associated with developing poor DS in the pooled cohorts; age and race/ethnicity were also significant factors. Conclusions: Our findings suggest that a CRC diagnosis is independently associated with a small increase in the risk of developing poor DS after accounting for other known factors. The study identified risk factors for developing poor DS in CRC survivors, including Hispanic and Black race/ethnicity, age, sex, histologic stage, and comorbidities. These findings underscore the importance of consistent physical function assessments, particularly among subsets of older survivors of CRC who are at higher risk of disability, to prevent developing poor DS.

5.
Pharmaceutics ; 16(4)2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38675217

ABSTRACT

Immunotherapy is a clinically effective method for treating tumors. Manganese can activate the cGAS-STING signaling pathway and induce an anti-tumor immune response. However, its efficacy is hindered by non-specific distribution and low uptake rates. In this study, we employed microfluidic technology to design and develop an innovative preparation process, resulting in the creation of a novel manganese lipid nanoparticle (LNM). The lipid manganese nanoparticle produced in this process boasts a high manganese payload, excellent stability, the capacity for large-scale production, and high batch repeatability. LNM has effectively demonstrated the ability to activate the cGAS-STING signaling pathway, induce the production of pro-inflammatory cytokines, and inhibit tumor development. Notably, LNM does not require combination chemotherapy drugs or other immune activators. Therefore, LNM presents a safe, straightforward, and efficient strategy for anti-tumor immune activation, with the potential for scalable production.

6.
J Colloid Interface Sci ; 664: 500-510, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38484518

ABSTRACT

The efficiency of CO2 photocatalytic reduction is severely limited by inefficient separation and sluggish transfer. In this study, spin polarization was induced and built-in electric field was strengthened via Co doping in the BiVO4 cell to boost photocatalytic CO2 reduction. Results showed that owing to the generation of spin-polarized electrons upon Co doping, carrier separation and photocurrent production of the Co-doped BiVO4 were enhanced. CO production during CO2 photocatalytic reduction from the Co-BiVO4 was 61.6 times of the BiVO4. Notably, application of an external magnetic field (100 mT) further boosted photocatalytic CO2 reduction from the Co-BiVO4, with 68.25 folds improvement of CO production compared to pristine BiVO4. The existence of a built-in electric field (IEF) was demonstrated through density functional theory (DFT) simulations and kelvin probe force microscopy (KPFM). Mechanism insights could be elucidated as follows: doping of magnetic Co into the BiVO4 resulted in increased the number of spin-polarized photo-excited carriers, and application of a magnetic field led to an augmentation of intrinsic electric field due to a dipole shift, thereby extending carrier lifetime and suppressing charges recombination. Additionally, HCOO- was a crucial intermediate in the process of CO2RR, and possible pathways for CO2 reduction were proposed. This study highlights the significance of built-in electric fields and the important role of spin polarization for promotion of photocatalytic CO2 reduction.

7.
Small ; : e2311916, 2024 Feb 12.
Article in English | MEDLINE | ID: mdl-38344887

ABSTRACT

Surface defects on photocatalysts could promote carrier separation and generate unsaturated sites for chemisorption and reactant activation. Nevertheless, the inactivation of oxygen vacancies (OVs) would deteriorate catalytic activity and limit the durability of defective materials. Herein, bagasse-derived carbon quantum dots (CQDs) are loaded on the Sn-doped Bi2 O2 CO3 (BOC) via hydrothermal procedure to create Bi─O─C chemical bonding at the interface, which not only provides efficient atomic-level interfacial electron channels for accelerating carriers transfer, but also enhances durability. The optimized Sn-BOC/CQDs-2 achieves the highest photocatalytic removal efficiencies for levofloxacin (LEV) (88.7%) and Cr (VI) (99.3%). The elimination efficiency for LEV and Cr (VI) from the Sn-BOC/CQDs-2 is maintained at 55.1% and 77.0% while the Sn-BOC is completely deactivated after four cycle tests. Furthermore, the key role of CQDs in stabilization of OVs is to replace OVs as the active center of H2 O and O2 adsorption and activation, thereby preventing reactant molecules from occupying OVs. Based on theoretical calculations of the Fukui index and intermediates identification, three possible degradation pathways of LEV are inferred. This work provides new insight into improving the stability of defective photocatalysts.

8.
Small ; : e2311816, 2024 Feb 23.
Article in English | MEDLINE | ID: mdl-38396322

ABSTRACT

Converting carbon dioxide (CO2 ) into high-value chemicals using solar energy remains a formidable challenge. In this study, the CSC@PM6:IDT6CN-M:IDT8CN-M non-fullerene small-molecule organic semiconductor is designed with highly efficient electron donor-acceptor (D-A) interface for photocatalytic reduction of CO2 . Atomic Force Microscope and Transmission Electron Microscope images confirmed the formation of an interpenetrating fibrillar network after combination of donor and acceptor. The CO yield from the CSC@PM6:IDT6CN-M:IDT8CN-M reached 1346 µmol g-1  h-1 , surpassing those of numerous reported inorganic photocatalysts. The D-A structure effectively facilitated charge separation to enable electrons transfer from the PM6 to IDT6CN-M:IDT8CN-M. Meanwhile, attributing to the dipole moments of the strong intermolecular interactions between IDT6CN-M and IDT8CN-M, the intermolecular forces are enhanced, and laminar stacking and π-π stacking are strengthened, thereby reinforcing energy transfer between acceptor molecules and significantly enhanced charge separation. Moreover, the strong internal electric field in the D-A interface enhanced the excited state lifetime of PM6:IDT6CN-M:IDT8CN-M. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) analysis demonstrated that carboxylate (COOH*) is the predominant intermediate during CO2 reduction, and possible pathways of CO2 reduction to CO are deduced. This study presents a novel approach for designing materials with D-A interface to achieve high photocatalytic activity.

9.
BMC Public Health ; 23(1): 2257, 2023 11 16.
Article in English | MEDLINE | ID: mdl-37974168

ABSTRACT

BACKGROUND: The growing prevalence of smartphone use among college students in China has led to health concerns, including De Quervain's Tenosynovitis (DQT). However, the specific smartphone usage behaviors contributing to DQT remain poorly understood. This study aimed to explore the relationship between smartphone usage behaviors and DQT in college students. METHODS: A cross-sectional study was conducted with 937 students from various majors in Guangxi between September 2021 and April 2022. Participants completed an online questionnaire assessing smartphone usage behaviors and their association with DQT. The Finkelstein test was employed to diagnose DQT. RESULTS: Over half of the college students (52%) tested positive for DQT via Finkelstein's test. Higher levels of smartphone usage time (6-8 h/day: OR = 4.454, 95%CI:1.662-12.229; ≥8 h/day: OR = 4.521, 95%CI:1.596-12.811), phone games (OR = 1.997, 95%CI:1.312-3.040), social media (OR = 2.263, 95%CI:1.795-3.833), and leisure activities (OR = 1.679, 95%CI:1.140-2.475) were significantly associated with an increased risk of DQT. Two specific gestures (Bilateral thumbs, BT: OR = 1.900, 95%CI:1.281-2.817; Bilateral thumbs-horizontal screen, BT-HS: OR = 1.872, 95%CI:1.244-2.818) and two screen sizes (5.0-5.5inch: OR = 2.064, 95%CI:1.108-3.846; 6.0-6.5inch: OR = 2.413, 95%CI:1.125-4.083) also exhibited a higher risk of DQT. Bilateral DQT was observed, with Gesture-BT identified as the primary risk factor. CONCLUSION: Our findings suggest that increased smartphone usage time, phone games, social media, and leisure activities elevate the risk of DQT among college students. Furthermore, two specific gestures and two screen sizes were also linked to a heightened DQT risk. To mitigate DQT development, college students should reduce smartphone usage time and adopt appropriate gestures.


Subject(s)
De Quervain Disease , Tenosynovitis , Humans , Tenosynovitis/complications , De Quervain Disease/complications , De Quervain Disease/diagnosis , De Quervain Disease/epidemiology , Smartphone , Cross-Sectional Studies , China/epidemiology , Students
10.
Heart Surg Forum ; 26(5): E628-E638, 2023 Oct 30.
Article in English | MEDLINE | ID: mdl-37920089

ABSTRACT

OBJECTIVES: For a long time, the association of the false lumen status and the outcomes of patients suffering from aortic dissection has been unclear, so this review article aims to study whether the unobstructed of the false lumen is related to the outcome of patients suffering from aortic dissection. METHODS: We performed this systematic review and meta-analysis according to the Preferred Reporting Items for Systematic Reviews and Meta Analyzes Protocols (PRISMA) statement 2009 and registered with PROSPERO (CRD42022381869). We searched PubMed, the Cochrane library, Web of Science and Embase to collect potential studies. The Newcastle-Ottawa Scale was used to assess the quality of the included studies. The main outcome is long-term survival. Data included in the study were summarized using the risk ratio or mean difference and 95% confidence interval. RESULTS: There were 16 trials, 2829 patients in total, with a mean age of 62.1 years. Compared with completely thrombosed false lumen, patent group has better long-term survival (risk ratio (RR), 0.88; 95% CI, 0.79 to 0.97; p = 0.01; I2 = 58%) and smaller yearly aortic growth rate (mean difference (MD), 1.03; 95% CI, 0.23 to 1.82; p = 0.01; I2 = 98%). In addition, patients with a patent false lumen had a lower risk of aortic event (RR, 0.81; 95% CI, 0.68 to 0.97; p = 0.02; I2 = 37%), but higher risk of aortic rupture (RR, 7.02; 95% CI, 2.55 to 19.3; p = 0.0002; I2 = 0) and hospital death (RR, 2.72; 95% CI, 1.45 to 5.08; p = 0.002; I2 = 0). CONCLUSION: Completely thrombosed of the false lumen is more beneficial to the long-term survival of patients with aortic dissection. And the risk of aortic rupture and hospital death in patients with patent false lumen is 7 times and 3 times that of patients with complete thrombosed false lumen. It is expected to provide individualized medical care for different types of patients according to different false lumen status to minimize death and related complications.


Subject(s)
Aortic Aneurysm, Thoracic , Aortic Dissection , Aortic Rupture , Endovascular Procedures , Thrombosis , Humans , Middle Aged , Aortic Dissection/diagnosis , Aortic Dissection/surgery , Aortic Rupture/etiology , Aortic Rupture/prevention & control , Retrospective Studies , Thrombosis/complications , Treatment Outcome
11.
Adv Mater ; : e2306350, 2023 Nov 21.
Article in English | MEDLINE | ID: mdl-37987498

ABSTRACT

Hydrogels have emerged as powerful building blocks to develop various soft bioelectronics because of their tissue-like mechanical properties, superior bio-compatibility, the ability to conduct both electrons and ions, and multiple stimuli-responsiveness. However, hydrogels are vulnerable to mechanical damage, which limits their usage in developing durable hydrogel-based bioelectronics. Self-healing hydrogels aim to endow bioelectronics with the property of repairing specific functions after mechanical failure, thus improving their durability, reliability, and longevity. This review discusses recent advances in self-healing hydrogels, from the self-healing mechanisms, material chemistry, and strategies for multiple properties improvement of hydrogel materials, to the design, fabrication, and applications of various hydrogel-based bioelectronics, including wearable physical and biochemical sensors, supercapacitors, flexible display devices, triboelectric nanogenerators (TENGs), implantable bioelectronics, etc. Furthermore, the persisting challenges hampering the development of self-healing hydrogel bioelectronics and their prospects are proposed. This review is expected to expedite the research and applications of self-healing hydrogels for various self-healing bioelectronics.

12.
PLoS One ; 18(10): e0293468, 2023.
Article in English | MEDLINE | ID: mdl-37903113

ABSTRACT

This study aims to restore grating lobe artifacts and improve the image resolution of sparse array ultrasonography via a deep learning predictive model. A deep learning assisted sparse array was developed using only 64 or 16 channels out of the 128 channels in which the pitch is two or eight times the original array. The deep learning assisted sparse array imaging system was demonstrated on ex vivo porcine teeth. 64- and 16-channel sparse array images were used as the input and corresponding 128-channel dense array images were used as the ground truth. The structural similarity index measure, mean squared error, and peak signal-to-noise ratio of predicted images improved significantly (p < 0.0001). The resolution of predicted images presented close values to ground truth images (0.18 mm and 0.15 mm versus 0.15 mm). The gingival thickness measurement showed a high level of agreement between the predicted sparse array images and the ground truth images, as indicated with a bias of -0.01 mm and 0.02 mm for the 64- and 16-channel predicted images, respectively, and a Pearson's r = 0.99 (p < 0.0001) for both. The gingival thickness bias measured by deep learning assisted sparse array imaging and clinical probing needle was found to be <0.05 mm. Additionally, the deep learning model showed capability of generalization. To conclude, the deep learning assisted sparse array can reconstruct high-resolution ultrasound image using only 16 channels of 128 channels. The deep learning model performed generalization capability for the 64-channel array, while the 16-channel array generalization would require further optimization.


Subject(s)
Deep Learning , Animals , Swine , Ultrasonography , Artifacts , Generalization, Psychological , Gingiva , Image Processing, Computer-Assisted
13.
Oncol Lett ; 26(5): 481, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37818138

ABSTRACT

[This retracts the article DOI: 10.3892/ol.2015.2904.].

14.
Int J Mol Sci ; 24(17)2023 Aug 29.
Article in English | MEDLINE | ID: mdl-37686170

ABSTRACT

Natural killer (NK) cells are cytotoxic lymphocytes that are critical for the innate immune system. Engineering NK cells with chimeric antigen receptors (CARs) allows CAR-NK cells to target tumor antigens more effectively. In this report, we present novel CAR mRNA-LNP (lipid nanoparticle) technology to effectively transfect NK cells expanded from primary PBMCs and to generate functional CAR-NK cells. CD19-CAR mRNA and BCMA-CAR mRNA were embedded into LNPs that resulted in 78% and 95% CAR expression in NK cells, respectively. BCMA-CAR-NK cells after transfection with CAR mRNA-LNPs killed multiple myeloma RPMI8226 and MM1S cells and secreted IFN-gamma and Granzyme B in a dose-dependent manner in vitro. In addition, CD19-CAR-NK cells generated with CAR mRNA-LNPs killed Daudi and Nalm-6 cells and secreted IFN-gamma and Granzyme B in a dose-dependent manner. Both BCMA-CAR-NK and CD19-CAR-NK cells showed significantly higher cytotoxicity, IFN-gamma, and Granzyme B secretion compared with normal NK cells. Moreover, CD19-CAR-NK cells significantly blocked Nalm-6 tumor growth in vivo. Thus, non-viral delivery of CAR mRNA-LNPs can be used to generate functional CAR-NK cells with high anti-tumor activity.


Subject(s)
Multiple Myeloma , Receptors, Chimeric Antigen , Humans , Receptors, Chimeric Antigen/genetics , Granzymes/genetics , B-Cell Maturation Antigen , Killer Cells, Natural , Multiple Myeloma/genetics , Multiple Myeloma/therapy , Adaptor Proteins, Signal Transducing , Antigens, CD19
15.
J Vis Exp ; (199)2023 09 08.
Article in English | MEDLINE | ID: mdl-37747218

ABSTRACT

This study presents a method utilizing heated ophthalmologic cautery to develop a viable model for investigating oronasal fistulas. C57BL/6 mice were used to establish the oronasal fistula (ONF) model. To create the ONF, the mice were anesthetized, immobilized, and their hard palates were exposed. During the surgical procedure, a 2.0 x 1.5 mm full-thickness mucosal injury was induced in the midline of the hard palate using ophthalmologic cautery. It was crucial to control the size of the ONF and minimize bleeding in order to ensure the success of the experiment. Verification of the ONF model's effectiveness was conducted on the 7th-day post-operation, encompassing both anatomical and functional assessments. The presence of the nasal septum within the oral cavity and the outflow of sterile water from the nostrils upon injection into the oral cavity confirmed the successful establishment of the ONF model. The model demonstrated a practical and successful oronasal fistula, characterized by a low mortality rate, significant weight changes, and minimal variation in ONF size. Future studies may consider adopting this methodology to elucidate the mechanisms of palate wound healing and explore novel treatments for oronasal fistulas.


Subject(s)
Fistula , Mouth , Animals , Mice , Mice, Inbred C57BL , Disease Models, Animal , Estrus , Fistula/surgery
16.
J Colloid Interface Sci ; 652(Pt B): 1126-1137, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-37657213

ABSTRACT

Photocatalytic conversion of carbon dioxide (CO2) into high value-added chemicals is an attractive yet challenging process, primarily due to the readily recombination of hole-electron pairs in photocatalysts. Herein, dual-oxygen-vacancy mediated Z-scheme Bi2Sn2O7/Sn/NiAl-layered double hydroxide (VO,O-20BSL) heterojunctions were hydrothermally synthesized and subsequently modified with Sn monomers to enhance photocatalytic activity toward CO2 reduction. The abundance of oxygen vacancies endowed the VO,O-20BSL with extended optical adsorption, enhanced charges separation, and superior CO2 adsorption and activation. The interfacial charges transfer of the VO,O-20BSL was demonstrated to follow a Z-scheme mechanism via photochemical deposition of metal/metal oxide. Under visible light irradiation, the VO,O-20BSL exhibited the highest yields of carbon monoxide (CO) and methane (CH4), with values of 72.03 and 0.85 umol·g-1·h-1, respectively, which were 2.66 and 1.57 times higher than that of the VO-NiAl-layered double hydroxide (VO-1LDH). In situ diffuse reflectance infrared fourier transform spectroscopy (DRIFTS) revealed that carboxylic acid groups (COOH*) and aldehyde groups (CHO*) were the predominant intermediates during CO2 reduction, and accordingly, possible CO2 reduction pathways and mechanism were proposed. This study presents a feasible approach to incorporate dual vacancies into Z-scheme heterojunctions for CO2 reduction.

17.
J Colloid Interface Sci ; 652(Pt A): 1006-1015, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-37639923

ABSTRACT

Designing Pt-skin on the catalyst surface is critical to developing efficient and stable electrocatalysts toward oxygen reduction reaction (ORR) in proton exchange membrane fuel cells. In this paper, an acidic reductant is proposed to synchronously manipulate in-situ growth of Pt-skin on the surface of alloyed Pt-Cu nanospheres (PtCuNSs) by a facile one-pot synthesis in an aqueous solution. Ascorbic acid can create a Pt-skin of three atomic layers to make the typical PtCu-alloy@Pt-skin core/shell nanostructure rather than the uniform alloys generated by using alkaline reductants. Surfactant as soft-template can make the alloyed PtCuNSs with a three-dimensional porous network structure. Multiple characterizations of XRD, XPS and XAFS are used to confirm Pt-alloying with Cu and formation of core/shell structure of such a catalyst. This PtCuNSs/C exhibits a half-wave potential of 0.913 V (vs. RHE), with mass activity and specific activity about 3.5 and 6.4 times higher than those of Pt/C, respectively. Fuel cell tests verify the excellent activity of PtCuNSs/C catalyst with a maximum power density of about 1.2 W cm-2. Moreover, this catalyst shows excellent stability, achieving a long-term operation of 40,000 cycles. Furthermore, theoretical calculations reveal the enhancement effect of characteristic PtCu-alloy@Pt-skin nanostructure on both catalytic ORR activity and stability.

18.
J Colloid Interface Sci ; 652(Pt A): 1043-1052, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-37639926

ABSTRACT

Visible-light-driven nicotinamide adenine dinucleotide (NADH) regeneration is one of the most effective measures, and cadmium sulfide (CdS) materials are typically used as low-cost photocatalysts. The CdS photocatalysts, however, still suffer from low regeneration efficiency and poor cycle stability. In this work, the CdS quantum dots (QDs) less than 10 nm embedded onto silica gel (CdS QDs/Silica gel) were constructed for visible-light-driven NADH regeneration by a successive ionic layer adsorption reaction and ball milling method. Results demonstrate that the photosensitivity of the CdS QDs/Silica gel composite was 31 times higher than that of the bulk CdS. Moreover, the conduction band (CB) edge of the CdS QDs/Silica gel composite is -1.34 eV, which is more negative 0.5 eV than that of the bulk CdS. The obtained CdS QDs/Silica gel composites showed the highest NADH regeneration yields of 68.8% under visible-light (LED, 420 nm) illumination and can be reused for over 40 cycles. Finally, the bioactivity of NADH toward enzyme catalysis is further confirmed by the hydrogenation of benzaldehyde to benzyl alcohol catalyzed with an alcohol dehydrogenase as enzyme catalysis.

19.
Int J Pediatr Otorhinolaryngol ; 171: 111607, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37329703

ABSTRACT

OBJECTIVE: Patients with a cleft palate often experience a velopharyngeal dysfunction known as velopharyngeal insufficiency (VPI). The purpose of this study was to examine the development of velopharyngeal function (VPF) following primary palatoplasty and the factors that are linked to it. METHODS: A retrospective study was conducted to examine the medical records of patients who had cleft palate, with or without cleft lip (CP ± L) and underwent palatoplasty at a Tertiary Affiliated Hospital between 2004 and 2017. Postoperative evaluation of VPF was conducted at two follow-up times (T1, T2) and was classified as either normal VPF, mild VPI, or moderate/severe VPI. The consistency of VPF evaluations between the two time points was then assessed, and patients were categorized into either the consistent or inconsistent group. The study collected and analyzed data on gender, cleft type, age at operation, follow-up duration, and speech records. RESULTS: The study included 188 patients with CP ± L. Out of these, 138 patients (73.4%) showed consistent VPF evaluations, while 50 patients (26.6%) showed inconsistent VPF evaluations. Among those with VPI at T1 (91 patients), 36 patients (39.6%) had normal VPF at T2. The rate of VPI decreased from 48.40% at T1 to 27.13% at T2, whereas the rate of normal VPF increased from 44.68% at T1 to 68.09% at T2. The consistent group had a significantly younger age at operation (2.90 ± 3.82 vs 3.68 ± 4.02), a longer duration of T1 (1.67 ± 0.97 vs 1.04 ± 0.59), and a lower comprehensive score of speech performance (1.86 ± 1.27 vs 2.60 ± 1.07) than the inconsistent group. CONCLUSIONS: It has been verified that there are changes in the development of VPF over time. Patients who underwent palatoplasty at a younger age were more likely to have confirmed VPF diagnosis at the first evaluation. The duration of follow-up was identified as a critical factor that affects the confirmation of VPF diagnosis.


Subject(s)
Cleft Palate , Velopharyngeal Insufficiency , Humans , Cleft Palate/surgery , Retrospective Studies , Treatment Outcome , Velopharyngeal Insufficiency/surgery
20.
iScience ; 26(5): 106730, 2023 May 19.
Article in English | MEDLINE | ID: mdl-37216112

ABSTRACT

Innovation of catalyst structure is extremely important to develop the high-performance electrocatalysts for oxygen-reduction reaction (ORR). Herein, nitrogen-doped carbon semi-tube (N-CST) is used as a functional support for stabilizing the microwave-reduced Pt nanoparticles with an average size of ∼2.8 nm to synthesize the semi-tubular Pt/N-CST catalyst. The contribution of interfacial Pt-N bond between N-CST support and Pt nanoparticles with electrons transfer from N-CST support to Pt nanoparticles is found by electron paramagnetic resonance (EPR) and X-ray absorption fine structure (XAFS) spectroscopy. This bridged Pt-N coordination can simultaneously help ORR electrocatalysis and promote electrochemical stability. As a result, the innovative Pt/N-CST catalyst exhibits excellent catalytic performance, realizing ORR activity and electrochemical stability superior to the commercial Pt/C catalyst. Furthermore, density functional theoretical (DFT) calculations suggest that the interfacial Pt-N-C site with unique affinity of O∗ + OH∗ can provide new active routes for the enhanced electrocatalytic ORR capacity.

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