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1.
J Colloid Interface Sci ; 665: 500-509, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38547631

RESUMEN

Constructing a heterojunction by combining two semiconductors with similar band structures is a successful approach to obtaining photocatalysts with high efficiency. Herein, a CuPc/DR-MoS2 heterojunction involving copper phthalocyanine (CuPc) and molybdenum disulfide with S-rich vacancies (13.66%) is successfully prepared by the facile hydrothermal method. Experimental results and theoretical calculations firmly demonstrated that photoelectrons exhibit an S-scheme charge transfer mechanism in the CuPc/DR-MoS2 heterojunction. The S-scheme heterojunction system has proven significant advantages in promoting the charge separation and transfer of photogenerated carriers, enhancing visible-light responsiveness, and achieving robust photoredox capability. As a result, the optimized 3CuPc/DR-MoS2 S-scheme heterojunction exhibits photocatalytic yields of CO and CH4 at 200 and 111.6 µmol g-1h-1, respectively. These values are four times and 4.5 times greater than the photocatalytic yields of pure DR-MoS2. This study offers novel perspectives on the advancement of innovative and highly effective heterojunction photocatalysts.

2.
J Colloid Interface Sci ; 663: 31-42, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38387184

RESUMEN

The construction of van der Waals (vdW) heterojunctions is a key approach for efficient and stable photocatalysts, attracting marvellous attention due to their capacity to enhance interfacial charge separation/transfer and offer reactive sites. However, when a vdW heterojunction is made through an ex-situ assembly, electron transmission faces notable obstacles at the components interface due to the substantial spacing and potential barrier. Herein, we present a novel strategy to address this challenge via wet chemistry by synthesizing a functionalized graphene-modulated Z-scheme vdW heterojunction of zinc phthalocyanine/tungsten trioxide (xZnPc/yG-WO3). The functionalized G-modulation forms an electron "bridge" across the ZnPc/WO3 interface to improve electron transfer, get rid of barriers, and ultimately facilitating the optimal transfer of excited photoelectrons from WO3 to ZnPc. The Zn2+ in ZnPc picks up these excited photoelectrons, turning CO2 into CO/CH4 (42/22 µmol.g-1.h-1) to deliver 17-times better efficiency than pure WO3. Therefore, the introduction of a molecular "bridge" as a means to establish an electron transfer conduit represents an innovative approach to fabricate efficient photocatalysts designed for the conversion of CO2 into valued yields.

3.
Nanoscale ; 16(9): 4352-4377, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38275275

RESUMEN

Semiconductor-based photocatalysis has attracted significant interest due to its capacity to directly exploit solar energy and generate solar fuels, including water splitting, CO2 reduction, pollutant degradation, and bacterial inactivation. However, achieving the maximum efficiency in photocatalytic processes remains a challenge owing to the speedy recombination of electron-hole pairs and the limited use of light. Therefore, significant endeavours have been devoted to addressing these issues. Specifically, well-designed heterojunction photocatalysts have been demonstrated to exhibit enhanced photocatalytic activity through the physical distancing of electron-hole pairs generated during the photocatalytic process. In this review, we provide a systematic discussion ranging from fundamental mechanisms to material strategies, focusing on TiO2-based heterojunction photocatalysts. Current efforts are focused on developing heterojunction photocatalysts based on TiO2 for a variety of photocatalytic applications, and these projects are explained and assessed. Finally, we offer a concise summary of the main insights and challenges in the utilization of TiO2-based heterojunction photocatalysts for photocatalysis. We expect that this review will serve as a valuable resource to improve the efficiency of TiO2-based heterojunctions for energy generation and environmental remediation.

4.
Anim Biosci ; 37(3): 500-508, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36915928

RESUMEN

OBJECTIVE: Due to current selection practices for increased egg production and peak persistency, the production profile, age at maturity, and body weight criteria for commercial layers are constantly changing. Body weight and age at the time of photostimulation will thus always be the factors that need to be adequately addressed among various production systems. The current study was carried out to determine the effects of pullets' body weight (low, medium, and heavy) on their performance, welfare, physiological response, and hormonal profile. METHODS: With regard to live weight, 150 16-week-old pullets were divided into three groups using a completely randomized design (CRD) and held until the 50th week. One-way analysis of variance was used to evaluate the data under the CRD, and the least significant difference test was used to distinguish between treatment means. RESULTS: In comparison to the medium and light birds, the heavy birds had higher body weight at maturity, an earlier age at maturity, and higher egg weight, eggshell weight, eggshell thickness, egg yolk index, breaking strength, egg surface area, egg shape index, egg volume, and hormonal profile except corticosterone. However, the medium and light birds had lower feed consumption rates per dozen eggs and per kilogram of egg mass than the heavy birds. Light birds showed greater body weight gain, egg production, and egg specific gravity than the other categories. At 20 weeks of age, physiological response, welfare aspects, and catalase were non-significant; however, at 50 weeks of age, all these factors-aside from catalase-were extremely significant. CONCLUSION: The findings of this study indicate that layers can function at lower body weights during photostimulation; hence, dietary regimens that result in lighter pullets may be preferable. Additionally, the welfare of the birds was not compromised by the lighter weight group.

5.
J Bronchology Interv Pulmonol ; 31(1): 63-69, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37246305

RESUMEN

BACKGROUND: Benign airway stenosis (BAS) represents a significant burden on patients, providers, and healthcare systems. Spray cryotherapy (SCT) has been proposed as an adjunctive treatment to reduce BAS recurrence. We sought to examine safety and practice variations of the latest SCT system when used for BAS. METHODS: We conducted a retrospective multicenter cohort study in seven academic institutions within the Interventional Pulmonary Outcomes Group. All patients who underwent at least one SCT session with a diagnosis of BAS at the time of procedure at these institutions were included. Demographics, procedure characteristics, and adverse events were captured through each center's procedural database and electronic health record. RESULTS: A total of 102 patients underwent 165 procedures involving SCT from 2013 to 2022. The most frequent etiology of BAS was iatrogenic (n = 36, 35%). In most cases, SCT was used prior to other standard BAS interventions (n = 125; 75%). The most frequent SCT actuation time per cycle was five seconds. Pneumothorax complicated four procedures, requiring tube thoracostomy in two. Significant post-SCT hypoxemia was noted in one case, with recovery by case conclusion and no long-term effects. There were no instances of air embolism, hemodynamic compromise, or procedural or in-hospital mortality. CONCLUSION: SCT as an adjunctive treatment for BAS was associated with a low rate of complications in this retrospective multicenter cohort study. SCT-related procedural aspects varied widely in examined cases, including actuation duration, number of actuations, and timing of actuations relative to other interventions.


Asunto(s)
Criocirugía , Crioterapia , Humanos , Estudios Retrospectivos , Estudios de Cohortes , Constricción Patológica/etiología , Crioterapia/efectos adversos , Criocirugía/efectos adversos
6.
ACS Nano ; 18(1): 288-298, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-37955363

RESUMEN

Modulation of the local electronic structure of isolated coordination structures plays a critical role in electrocatalysis yet remains a grand challenge. Herein, we have achieved electron perturbation for the isolated iron coordination structure via tuning the iron spin state from a high spin state (FeN4) to a medium state (FeN2B2). The transition of spin polarization facilitates electron penetration into the antibonding π orbitals of nitrogen and effectively activates nitrogen molecules, thereby achieving an ammonia yield of 115 µg h-1 mg-1cat. and a Faradaic efficiency of 24.8%. In situ spectroscopic studies and theoretical calculations indicate that boron coordinate sites, as electron acceptors, can regulate the adsorption energy of NxHy intermediates on the Fe center. FeN2B2 sites favor the NNH* intermediate formation and reduce the energy barrier of rate-determining steps, thus accounting for excellent nitrogen fixation performance. Our strategy provides an effective approach for designing efficient electrocatalysts via precise electronic perturbation.

7.
Angew Chem Int Ed Engl ; 62(48): e202305385, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-37530435

RESUMEN

Transition metal oxides (TMOs) were one of the first photocatalysts used to produce hydrogen from water using solar energy. Despite the emergence of many other genres of photocatalysts over the years, TMO photocatalysts remain dominant due to their easy synthesis and unique physicochemical properties. Various strategies have been developed to enhance the photocatalytic activity of TMOs, but the solar-to-hydrogen (STH) conversion efficiency of TMO photocatalysts is still very low (<2 %), which is far below the targeted STH of 10 % for commercial viability. This article provides a comprehensive analysis of several widely used strategies, including oxygen defects control, doping, establishing interfacial junctions, and phase-facet-morphology engineering, that have been adopted to improve TMO photocatalysts. By critically evaluating these strategies and providing a roadmap for future research directions, this article serves as a valuable resource for researchers, students, and professionals seeking to develop efficient energy materials for green energy solutions.

8.
Adv Mater ; 35(38): e2303047, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37363951

RESUMEN

Constructing Van der Waals heterojunction is a crucial strategy to achieve excellent photocatalytic activity. However, in most Van der Waals heterojunctions synthesized by ex situ assembly, electron transfer encounters huge hindrances at the interface between the two components due to the large spacing and potential barrier. Herein, a phosphate-bridged Van der Waals heterojunction of cobalt phthalocyanine (CoPc)/tungsten disulfide (WS2 ) bridged by phosphate (xCoPc-nPO4 - -WS2 ) is designed and prepared by the traditional wet chemistry method. By introducing a small phosphate molecule into the interface of CoPc and WS2 , creates an electron "bridge", resulting in a compact combination and eliminating the space barrier. Therefore, the phosphate (PO4 - ) bridge can serve as an efficient electron transfer channel in heterojunction and can efficiently transmit photoelectrons from WS2 to CoPc under excited states. These excited photoelectrons are captured by the catalytic central Co2+ in CoPc and subsequently convert CO2 molecules into CO and CH4 products, achieving 17-fold enhancement on the 3CoPc-0.6PO4 - -WS2 sample compared to that of pure WS2 . Introducing a small molecule "bridge" to create an electron transfer channel provides a new perspective in designing efficient photocatalysts for photocatalytic CO2 reduction into valuable products.

9.
Small ; 19(25): e2208179, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36935369

RESUMEN

The realization of solar-light-driven CO2  reduction reactions (CO2 RR) is essential for the commercial development of renewable energy modules and the reduction of global CO2 emissions. Combining experimental measurements and theoretical calculations, to introduce boron dopants and nitrogen defects in graphitic carbon nitride (g-C3 N4 ), sodium borohydride is simply calcined with the mixture of g-C3 N4 (CN), followed by the introduction of ultrathin Co phthalocyanine through phosphate groups. By strengthening H-bonding interactions, the resultant CoPc/P-BNDCN nanocomposite showed excellent photocatalytic CO2 reduction activity, releasing 197.76 and 130.32 µmol h-1  g-1 CO and CH4 , respectively, and conveying an unprecedented 10-26-time improvement under visible-light irradiation. The substantial tuning is performed towards the conduction and valance band locations by B-dopants and N-defects to modulate the band structure for significantly accelerated CO2 RR. Through the use of ultrathin metal phthalocyanine assemblies that have a lot of single-atom sites, this work demonstrates a sustainable approach for achieving effective photocatalytic CO2 activation. More importantly, the excellent photoactivity is attributed to the fast charge separation via Z-scheme transfer mechanism formed by the universally facile strategy of dimension-matched ultrathin (≈4 nm) metal phthalocyanine-assisted nanocomposites.

10.
Environ Sci Pollut Res Int ; 29(22): 32594-32604, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35195862

RESUMEN

Genetically, modern broilers are fast-growing birds which attain the market age at the age of 5 weeks. To maintain optimum production, antibiotics have been commonly included in the diets as growth promoters. However, due to the increase in antimicrobial resistance, their uses have been banned worldwide. To keep the optimum level of production and health in broiler industry, the use of alternative growth promoters such as probiotics, prebiotics, enzymes, and organic acids has been proposed. Chemically, organic acids are weak acids and only partially dissociate. They are considered safe and have been used for preservation of food for centuries. Nowadays, organic acids have been reported for antibacterial, immune potentiating, and growth promoters in broilers. In this review, the effects of dietary inclusion of organic acids on growth, nutrient digestibility, intestinal integrity, immune system, and antibacterial activity in broilers are discussed.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Pollos , Ácidos/farmacología , Alimentación Animal/análisis , Animales , Antibacterianos/farmacología , Dieta/veterinaria , Suplementos Dietéticos , Digestión , Compuestos Orgánicos
12.
Adv Sci (Weinh) ; 9(2): e2102530, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34859614

RESUMEN

Artificial Z-scheme, a tandem structure with two-step excitation process, has gained significant attention in energy production and environmental remediation. By effectively connecting and matching the band-gaps of two different photosystems, it is significant to utilize more photons for excellent photoactivity. Herein, a novel one-photon (same energy-two-photon) Z-scheme system is constructed between rGO modified boron-nitrogen co-doped-WO3 , and coupled CdSe quantum dots-(QDs). The coctalyst-0.5%Rhx Cr2 O3 (0.5RCr) modified amount-optimized sample 6%CdSe/1%rGO3%BN-WO3 revealed an unprecedented visible-light driven overall-water-splitting to produce ≈51 µmol h-1 g-1 H2 and 25.5 µmol h-1 g-1 O2 , and it remained unchanged for 5 runs in 30 h. This superior performance is ascribed to the one-photon Z-scheme, which simultaneously stimulates a two photocatalysts system, and enhanced charge separation as revealed by various spectroscopy techniques. The density-functional theory is further utilized to understand the origin of this performance enhancement. This work provides a feasible strategy for constructing an efficient one-photon Z-scheme for practical applications.

14.
ACS Appl Mater Interfaces ; 13(49): 58566-58575, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34852196

RESUMEN

Perovskite oxides have emerged as promising candidates for the oxygen evolution reaction (OER) electrocatalyst due to their flexible lattice structure, tunable electronic structure, superior stability, and cost-effectiveness. Recent research studies have mostly focused on the traditional methods to tune the OER performance, such as cation/anion doping, A-/B-site ordering, epitaxial strain, oxygen vacancy, and so forth, leading to reasonable yet still limited activity enhancement. Here, we report a novel strategy for promoting the OER activity for perovskite LaNiO3 by crystal phase engineering, which is realized by breaking long-range chemical bonding through amorphization. We provide the first and direct evidence that perovskite oxides with an amorphous structure can induce the self-adaptive process, which helps enhance the OER performance. This is evidenced by the fact that an amorphous LaNiO3 film on glassy carbon shows a 9-fold increase in the current density compared to that of an epitaxial LaNiO3 single crystalline film. The obtained current density of 1038 µΑ cm-2 (@ 1.6 vs RHE) is the largest value among the literature reported values. Our work thus offers a new protocol to boost the OER performance for perovskite oxides for future clean energy applications.

15.
BMJ Case Rep ; 14(4)2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33795283

RESUMEN

A 59-year-old woman presented to the emergency department with shortness of breath. She had significant oropharyngeal swelling obstructing her upper respiratory tract. A diagnosis of laryngeal myxoedema was made, which was attributed to severe hypothyroidism. She required invasive ventilation and subsequently a tracheostomy. She was treated with levothyroxine and hydrocortisone. She completely recovered with this therapy. In this review, we will discuss similar cases and different therapeutic options. This case also highlights the fact that establishing a diagnosis of laryngeal myxoedema, a condition that can potentially have lethal outcomes and can be challenging.


Asunto(s)
Hipotiroidismo , Laringe , Mixedema , Femenino , Humanos , Hipotiroidismo/complicaciones , Hipotiroidismo/tratamiento farmacológico , Laringe/diagnóstico por imagen , Persona de Mediana Edad , Mixedema/complicaciones , Mixedema/diagnóstico , Mixedema/tratamiento farmacológico , Tiroxina/uso terapéutico , Traqueostomía
16.
Case Rep Crit Care ; 2021: 8850116, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33688441

RESUMEN

Dexmedetomidine is an α2-adrenergic used as an adjunct therapy for sedation in the intensive care unit. While it is known to cause polyuria exclusively in perioperative conditions, not many cases are known in the intensive care unit, thus making the diagnosis challenging. We present the case of a 61-year-old male who had developed polyuria secondary to central diabetes insipidus after receiving dexmedetomidine intravenous infusion in the medical ICU. Increased awareness of this uncommon side effect of dexmedetomidine will help clinicians recognize and address it early.

17.
Perm J ; 252021 12 10.
Artículo en Inglés | MEDLINE | ID: mdl-35348081

RESUMEN

INTRODUCTION: Breast cancer is the most common malignancy affecting women in US today. Radiotherapy used after breast-conserving surgery has been shown to decrease local recurrence while minimizing side effects. Peripheral neuropathy remains a common and well-known complication of radiotherapy for breast cancer; however, it is rarely associated with phrenic nerve palsy after treatment of breast cancer. CASE PRESENTATION: We describe a 66-year-old woman with a significant past medical history of chronic obstructive pulmonary disease and asthma who presented with hypoxia after completing radiotherapy for breast cancer. After ruling out other causes of hypoxemia, the patient was diagnosed with diaphragmatic dysfunction, likely caused by phrenic nerve palsy resulting from radiotherapy-induced neuropathy after treatment of breast cancer. CONCLUSION: This case is the first reported incidence of phrenic nerve palsy resulting from radiotherapy for breast cancer.


Asunto(s)
Neoplasias de la Mama , Enfermedades del Sistema Nervioso Periférico , Anciano , Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/cirugía , Femenino , Humanos , Mastectomía Segmentaria , Parálisis/etiología , Parálisis/cirugía , Enfermedades del Sistema Nervioso Periférico/etiología , Enfermedades del Sistema Nervioso Periférico/cirugía , Nervio Frénico
18.
BMJ Case Rep ; 13(11)2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-33257389

RESUMEN

We present here a case of a 29-year-old woman with a medical history of GATA-2 deficiency, who was under treatment for Mycobacterium avium intracellulare pneumonia. She presented with worsening dyspnoea with cough and fever. It was initially thought she had pneumonia but she was later diagnosed with Pulmonary Alveolar Proteinosis (PAP).


Asunto(s)
Deficiencia GATA2/complicaciones , Proteinosis Alveolar Pulmonar/etiología , Adulto , Lavado Broncoalveolar , Líquido del Lavado Bronquioalveolar/citología , Líquido del Lavado Bronquioalveolar/microbiología , Diagnóstico Diferencial , Disnea/etiología , Femenino , Humanos , Pulmón/diagnóstico por imagen , Pulmón/patología , Complejo Mycobacterium avium , Neumonía Bacteriana/complicaciones , Neumonía Bacteriana/microbiología , Proteinosis Alveolar Pulmonar/diagnóstico por imagen , Proteinosis Alveolar Pulmonar/terapia , Radiografía Torácica , Pruebas de Función Respiratoria
19.
BMJ Case Rep ; 13(4)2020 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-32303527

RESUMEN

A 45-year-old woman with a medical history of ulcerative colitis (UC) presented with difficulty in breathing. The patient was diagnosed with UC a month prior to presentation and was started on mesalamine suppository. Chest x-ray (CXR) on presentation showed bilateral pleural effusion, which was confirmed on CT angiogram of the chest. Diagnostic and therapeutic thoracentesis was performed and 0.7 L of pleural fluid was removed from the left side. The pleural fluid analysis was consistent with exudative pleural effusion with eosinophilia. Symptomatic improvement was noted after thoracentesis. Mesalamine was stopped and repeat CXR was obtained on the follow-up visit, which showed no pleural effusion. The Naranjo score was calculated to be 7, indicating that the eosinophilic pleural effusion was most probably secondary to adverse reaction from mesalamine.


Asunto(s)
Eosinofilia/inducido químicamente , Mesalamina/efectos adversos , Derrame Pleural/inducido químicamente , Antiinflamatorios no Esteroideos/efectos adversos , Colitis Ulcerosa/complicaciones , Colitis Ulcerosa/tratamiento farmacológico , Diagnóstico Diferencial , Eosinofilia/terapia , Femenino , Humanos , Persona de Mediana Edad , Derrame Pleural/terapia , Toracocentesis
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 235: 118303, 2020 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-32276226

RESUMEN

Different plants can be used to prepare nanoparticles. This is termed as green technology. It is one of the best ecofriendly and low-cost method for the preparation of nanoparticles which has no harmful effects. PbO nanoparticles were prepared by green method using leaf extract of Datura Sternum plants. The preparation of Lead oxide was confirmed by color change from colorless to yellowish brown. UV-Visible peak obtained at 250 nm and XRD study clarified the formation of PbO NPs. These PbO nanoparticles were then applied for the preparation of Nano Composite Polymer Membranes (nCPMs). PbO-PVC nCPMs were prepared based on polyvinyl chloride (PVC) polymer and PbO filler with the help of solution casting method, using cyclohexanone as a solvent. Different percentage (5-35%) of filler was used. The physiochemical parameters studied were viscosity, water uptake (WU), perpendicular swelling (DT) in deionized water, density, porosity (ε), morphology, ion adsorption capacity (IAC) and electrical conductivity (σ). The values of all these parameters except viscosity and conductivity were increased on increasing filler percentage. Viscosity of the nCPMs solution was decreased from 171 to 46.21. The conductivity of nCPMs was first increased upto 25% filler and then decreased. The deformation in PVC structure was increased on enhancing PbO amount. The values of Density, porosity, water uptake, DT and IAC were found in range 1.15-5.02, 0.50-0.87, 72.01-141.30, 0.012-0.11, and 3.13 × 107-8.60 × 107 respectively.


Asunto(s)
Datura/química , Tecnología Química Verde/métodos , Plomo/química , Nanopartículas del Metal/química , Nanocompuestos/química , Óxidos/química , Cloruro de Polivinilo/química , Adsorción , Ciclohexanonas/química , Conductividad Eléctrica , Iones , Membranas Artificiales , Nanopartículas/química , Porosidad , Espectrofotometría Ultravioleta , Viscosidad , Contaminantes Químicos del Agua/química , Difracción de Rayos X
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