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1.
Small ; 20(24): e2310529, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38148294

RESUMO

2D organic-inorganic hybrid perovskites (OIHPs) have become one of the hottest research topics due to their excellent environmental stability and unique optoelectronic properties. Recently, the ferroelectricity and thermochromism of 2D OIHPs have attracted increasing interests. Integrating ferroelectricity and thermochromism into perovskites can significantly promote the development of multichannel intelligent devices. Here, a novel 2D Dion-Jacobson OIHP of the formula (3AMP)PbI4 (where 3AMP is 3-(aminomethyl)pyridinium) is reported, which has a remarkable spontaneous polarization value (Ps) of 15.6 µC cm-2 and interesting thermochromism. As far it is known, such a large Ps value is the highest for 2D OIHPs recorded so far. These findings will inspire further exploration and application of multifunctional perovskites.

2.
Surg Endosc ; 38(1): 179-185, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37950029

RESUMO

BACKGROUND: Penile carcinoma is an uncommon cancer that develops in the penis tissue. The standard surgical method to manage regional lymph nodes after local excision is radical inguinal lymphadenectomy, but it has a high rate of complications. The objective of this retrospective study was to compare the long-term outcomes of endoscopic inguinal lymphadenectomy and open inguinal lymphadenectomy in patients with penile carcinoma. METHODS: The study included patients diagnosed with penile carcinoma who underwent open inguinal lymphadenectomy (n = 23) or endoscopic inguinal lymphadenectomy (n = 27) at a single hospital between January 2013 and January 2021. Operation time, blood loss, drainage, hospital stay, postoperative complications, and survival rates were assessed and compared between the two groups. RESULTS: The two groups were comparable in terms of age, tumor size and stage, inguinal lymph nodes, and follow-up. The endoscopic group had significantly lower blood loss (27.1 ± 1.5 ml vs 55.0 ± 2.7 ml, P < 0.05), shorter drainage time and hospital stay (4.7 ± 1.1 days vs 8.1 ± 2.2 days, and 13.4 ± 1.0 days vs 19 ± 2.0 days, respectively, P < 0.05), and longer operation time compared to the open group (82.2 ± 4.3 min in endoscopic group vs 53.1 ± 2.2 min in open group, P < 0.05). There were significant differences in the incidence of incisional infection, necrosis, and lymphorrhagia in both groups (4 vs 0, 4 vs 0, and 2 vs 0, respectively, P < 0.05). The inguinal lymph node harvested was comparable between the two groups. The mean follow-up time was similar for both groups (60.4 ± 7.7 m vs 59.8 ± 7.3 m), and the recurrence mortality rates were not significantly different. CONCLUSIONS: The study shows that both open and endoscopic methods work well for controlling penile carcinoma in the long term. But the endoscopic approach is better because it has fewer severe complications. So, the choice of surgery method might depend on factors like the surgeon's experience, what they like, and what resources are available.


Assuntos
Carcinoma , Neoplasias Penianas , Masculino , Humanos , Seguimentos , Estudos Retrospectivos , Cirurgia Vídeoassistida/métodos , Canal Inguinal , Excisão de Linfonodo/métodos , Neoplasias Penianas/cirurgia , Neoplasias Penianas/patologia , Carcinoma/cirurgia
3.
Acta Derm Venereol ; 104: adv24050, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38932592

RESUMO

To examine the prevalence of comorbidities in Chinese urticaria patients and assess medication use patterns across different ages (6-11 years, 12-17 years, above 18 years), a retrospective cohort study was performed in 192,647 urticaria patients within the Health Database. After 1:1 propensity score matching, 166,921 people were divided into the urticaria group and the control group, and the follow-up data were collected within 2 years. During the 12-month and 24-month follow-up period, significant comorbidities identified included allergic rhinitis and asthma, with distinct patterns observed across age groups. Chronic urticaria patients often have complications, such as allergic rhinitis, upper respiratory infection, oropharyngeal infection, and dental caries. The study underscores the need for age-specific treatment strategies in urticaria management.


Assuntos
Urticária Crônica , Comorbidade , Humanos , Estudos Retrospectivos , Criança , Masculino , Adolescente , Feminino , China/epidemiologia , Prevalência , Fatores Etários , Adulto Jovem , Urticária Crônica/epidemiologia , Urticária Crônica/tratamento farmacológico , Adulto , Rinite Alérgica/epidemiologia , Fatores de Tempo , Urticária/epidemiologia , Urticária/diagnóstico , Fatores de Risco , Pontuação de Propensão , Pessoa de Meia-Idade , Bases de Dados Factuais , Asma/epidemiologia , Asma/tratamento farmacológico , Asma/diagnóstico , População do Leste Asiático
4.
Molecules ; 29(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38999013

RESUMO

Propane dehydrogenation (PDH) is a crucial approach for propylene production. However, commonly used CrOx-based catalysts have issues including easy sintering at elevated reaction temperatures and relying on high acidity supports. In this work, we develop a strategy, to strongly anchor and isolate active sites against their commonly observed aggregation during reactions, by taking advantage of the net trap effect in chromate intercalated Zn-Cr layered hydroxides as precursors. Furthermore, the intercalated chromate overcomes the collapse of traditional layered hydroxides during their transformation to metal oxide, thus exposing more available active sites. A joint fine modulation including crystal structure, surface acidity, specific surface area, and active sites dispersion is performed on the final mixed metal oxides for propane dehydrogenation. As a result, Zn1Cr2-CrO42--MMO delivers attractive propane conversion (~27%) and propylene selectivity (>90%) as compared to other non-noble-metal-based catalysts.

5.
Angew Chem Int Ed Engl ; 63(24): e202405493, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38604975

RESUMO

Synthesis of ammonia by electrochemical nitrogen reduction reaction (NRR) is a promising alternative to the Haber-Bosch process. However, it is commonly obstructed by the high activation energy. Here, we report the design and synthesis of an Al-Al bonded dual atomic catalyst stabilized within an amorphous nitrogen-doped porous carbon matrix (Al2NC) with high NRR performance. The dual atomic Al2-sites act synergistically to catalyze the complex multiple steps of NRR through adsorption and activation, enhancing the proton-coupled electron transfer. This Al2NC catalyst exhibits a high Faradaic efficiency of 16.56±0.3 % with a yield rate of 29.22±1.2 µg h-1 mgcat -1. The dual atomic Al2NC catalyst shows long-term repeatable, and stable NRR performance. This work presents an insight into the identification of synergistic dual atomic catalytic site and mechanistic pathway for the electrochemical conversion of N2 to NH3.

6.
Angew Chem Int Ed Engl ; 63(27): e202320014, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38598078

RESUMO

Amino acids are the building blocks of proteins and are widely used as important ingredients for other nitrogen-containing molecules. Here, we report the sustainable production of amino acids from biomass-derived hydroxy acids with high activity under visible-light irradiation and mild conditions, using atomic ruthenium-promoted cadmium sulfide (Ru1/CdS). On a metal basis, the optimized Ru1/CdS exhibits a maximal alanine formation rate of 26.0 molAla ⋅ gRu -1 ⋅ h-1, which is 1.7 times and more than two orders of magnitude higher than that of its nanoparticle counterpart and the conventional thermocatalytic process, respectively. Integrated spectroscopic analysis and density functional theory calculations attribute the high performance of Ru1/CdS to the facilitated charge separation and O-H bond dissociation of the α-hydroxy group, here of lactic acid. The operando nuclear magnetic resonance further infers a unique "double activation" mechanism of both the CH-OH and CH3-CH-OH structures in lactic acid, which significantly accelerates its photocatalytic amination toward alanine.


Assuntos
Aminoácidos , Biomassa , Compostos de Cádmio , Rutênio , Sulfetos , Sulfetos/química , Rutênio/química , Compostos de Cádmio/química , Catálise , Aminoácidos/química , Processos Fotoquímicos , Teoria da Densidade Funcional , Luz
7.
Mol Pharmacol ; 104(4): 133-143, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37419692

RESUMO

Licorice is a traditional Chinese medicine and recorded to have pain relief effects in national pharmacopoeia, but the mechanisms behind these effects have not been fully explored. Among the hundreds of compounds in licorice, licochalcone A (LCA) and licochalcone B (LCB) are two important components belonging to the chalcone family. In this study, we compared the analgesic effects of these two licochalcones and the molecular mechanisms. LCA and LCB were applied in cultured dorsal root ganglion (DRG) neurons, and the voltage-gated sodium (NaV) currents and action potentials were recorded. The electrophysiological experiments showed that LCA can inhibit NaV currents and dampen excitabilities of DRG neurons, whereas LCB did not show inhibition effect on NaV currents. Because the NaV1.7 channel can modulate Subthreshold membrane potential oscillations in DRG neuron, which can palliate neuropathic pain, HEK293T cells were transfected with NaV1.7 channel and recorded with whole-cell patch clamp. LCA can also inhibit NaV1.7 channels exogenously expressed in HEK293T cells. We further explored the analgesic effects of LCA and LCB on formalin-induced pain animal models. The animal behavior tests revealed that LCA can inhibit the pain responses during phase 1 and phase 2 of formalin test, and LCB can inhibit the pain responses during phase 2. The differences of the effects on NaV currents between LCA and LCB provide us with the basis for developing NaV channel inhibitors, and the novel findings of analgesic effects indicate that licochalcones can be developed into effective analgesic medicines. SIGNIFICANCE STATEMENT: This study found that licochalcone A (LCA) can inhibit voltage-gated sodium (NaV) currents, dampen excitabilities of dorsal root ganglion neurons, and inhibit the NaV1.7 channels exogenously expressed in HEK293T cells. Animal behavior tests showed that LCA can inhibit the pain responses during phase 1 and phase 2 of formalin test, whereas licochalcone B can inhibit the pain responses during phase 2. These findings indicate that licochalcones could be the leading compounds for developing NaV channel inhibitors and effective analgesic medicines.


Assuntos
Neuralgia , Canais de Sódio Disparados por Voltagem , Animais , Humanos , Bloqueadores dos Canais de Sódio/farmacologia , Células HEK293 , Gânglios Espinais , Sódio , Canal de Sódio Disparado por Voltagem NAV1.7
8.
J Biol Chem ; 298(1): 101457, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34861238

RESUMO

Toxin-antitoxin (TA) systems are ubiquitous regulatory modules for bacterial growth and cell survival following stress. YefM-YoeB, the most prevalent type II TA system, is present in a variety of bacterial species. In Staphylococcus aureus, the YefM-YoeB system exists as two independent paralogous copies. Our previous research resolved crystal structures of the two oligomeric states (heterotetramer and heterohexamer-DNA ternary complex) of the first paralog as well as the molecular mechanism of transcriptional autoregulation of this module. However, structural details reflecting molecular diversity in both paralogs have been relatively unexplored. To understand the molecular mechanism of how Sa2YoeB and Sa2YefM regulate their own transcription and how each paralog functions independently, we solved a series of crystal structures of the Sa2YoeB-Sa2YefM. Our structural and biochemical data demonstrated that both paralogous copies adopt similar mechanisms of transcriptional autoregulation. In addition, structural analysis suggested that molecular diversity between the two paralogs might be reflected in the interaction profile of YefM and YoeB and the recognition pattern of promoter DNA by YefM. Interaction analysis revealed unique conformational and activating force effected by the interface between Sa2YoeB and Sa2YefM. In addition, the recognition pattern analysis demonstrated that residues Thr7 and Tyr14 of Sa2YefM specifically recognizes the flanking sequences (G and C) of the promoter DNA. Together, these results provide the structural insights into the molecular diversity and independent function of the paralogous copies of the YoeB-YefM TA system.


Assuntos
Antitoxinas , Toxinas Bacterianas , DNA Bacteriano , Staphylococcus aureus , Sistemas Toxina-Antitoxina , Antitoxinas/química , Antitoxinas/metabolismo , Toxinas Bacterianas/química , Toxinas Bacterianas/metabolismo , DNA Bacteriano/metabolismo , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo
9.
Mol Med ; 29(1): 154, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37936054

RESUMO

BACKGROUND: Tyrosine kinase and phosphoinositide kinase pathways play important roles in asthma formation. As a dual tyrosine and phosphoinositide kinase inhibitor, PP121 has shown anticancer efficacy in multiple tumors. However, the study of PP121 in pulmonary diseases is still limited. Herein, we investigated the therapeutic activities of PP121 in asthma treatment. METHODS: Tension measurements and patch clamp recordings were made to investigate the anticontractile characteristics of PP121 in vitro. Then, an asthma mouse model was established to further explore the therapeutic characteristics of PP121 via measurement of respiratory system resistance, histological analysis and western blotting. RESULTS: We discovered that PP121 could relax precontracted mouse tracheal rings (mTRs) by blocking certain ion channels, including L-type voltage-dependent Ca2+ channels (L-VDCCs), nonselective cation channels (NSCCs), transient receptor potential channels (TRPCs), Na+/Ca2+ exchangers (NCXs) and K+ channels, and accelerating calcium mobilization. Furthermore, PP121 relieved asthmatic pathological features, including airway hyperresponsiveness, systematic inflammation and mucus secretion, via downregulation of inflammatory factors, mucins and the mitogen-activated protein kinase (MAPK)/Akt signaling pathway in asthmatic mice. CONCLUSION: In summary, PP121 exerts dual anti-contractile and anti-inflammatory effects in asthma treatment, which suggests that PP121 might be a promising therapeutic compound and shed new light on asthma therapy.


Assuntos
Asma , Hipersensibilidade Respiratória , Animais , Camundongos , 1-Fosfatidilinositol 4-Quinase/metabolismo , Asma/tratamento farmacológico , Hipersensibilidade Respiratória/metabolismo , Inflamação/metabolismo , Muco/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos BALB C , Ovalbumina
10.
Opt Express ; 31(8): 12410-12422, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37157401

RESUMO

A compact single-polarization (SP) coupler based on a dual-hollow-core anti-resonant fiber (DHC-ARF) is proposed. By introducing a pair of thick-wall tubes into a ten-tube single-ring hollow-core anti-resonant fiber, the core is separated into two cores to form the DHC-ARF. More importantly, by introducing the thick-wall tubes, dielectric modes in the thick wall are excited to inhibit the mode-coupling of secondary eigen-state of polarization (ESOP) between two cores while the mode-coupling of the primary ESOP can be enhanced, and thus the coupling length (Lc) of the secondary ESOP is greatly increased and that of primary ESOP is reduced to several millimeters. Simulation results show that the Lc of the secondary ESOP is up to 5549.26 mm and one of the primary ESOP is only 3.12 mm at 1550 nm through optimizing fiber structure parameters. By using a 1.53-mm-long DHC-ARF, a compact SP coupler can be implemented with a polarization extinction ratio (PER) less than - 20 dB within the wavelength range from 1547 nm to 1551.4 nm, and the lowest PER of - 64.12 dB is achieved at 1550 nm. Its coupling ratio (CR) is stable within 50 ± 2% in the wavelength range from 1547.6 nm to 1551.4 nm. The novel compact SP coupler provides a reference for developing HCF-based polarization-dependent components for use in the high-precision miniaturized resonant fiber optic gyroscope.

11.
Opt Express ; 31(16): 26178-26193, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710485

RESUMO

A high-birefringence and low-loss terahertz (THz) hollow-core anti-resonant fiber (THz HC-ARF) is designed and analyzed numerically by the finite element method (FEM). The THz HC-ARF is composed of an elliptical tube as the core for high birefringence guidance and a pair of symmetrical slabs arranged vertically as the cladding to attain low loss. Numerical analysis indicates that the birefringence reaches 10-2 in the transmission window between 0.21 and 0.35 THz. The highest birefringence is 4.61 × 10-2 at 0.21 THz with a loss of 0.15 cm-1. To verify the theoretical results, the THz HC-ARF is produced by three-dimensional (3D) printing, and the transmission characteristics are determined by THz time-domain spectroscopy (THz-TDS). High birefringence in the range of 2.17 × 10-2 to 3.72 × 10-2 and low loss in the range of 0.12 to 0.18 cm-1 are demonstrated experimentally in the 0.2 to 0.27 THz transmission window. The highest birefringence is 3.72 × 10-2 at 0.22 THz and the corresponding loss is 0.18 cm-1. The THz HC-ARF shows the highest birefringence besides relatively low loss compared to similar THz HC-ARFs reported recently.

12.
Opt Express ; 31(18): 29877-29886, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37710777

RESUMO

An ultra-broadband 3-dB coupler based on a polymer dual-hollow-core anti-resonant fiber (DHC-ARF) is designed to work in the E + S + C + L + U communication band. By incorporating two elliptical-like cores and modulating the air gap between the two cores, the wavelength and polarization dependence of the DHC-ARF-based coupler is reduced effectively. The feasibility of using a 1.46 cm long DHC-ARF as the ultra-broadband coupler for the operating bandwidth of 400 nm in the range between 1.33 µm and 1.73 µm is demonstrated theoretically. The coupling ratio of each polarized mode stabilizes at 50 ± 2% and the coupling ratio difference between the two polarized modes changes within ±0.6%. This DHC-ARF coupler which is made of a polymer can be fabricated by high-resolution 3D printing. Compared to a silica-based DHC-ARF coupler, the polymer-based DHC-ARF coupler is easier to manufacture and the total loss of the latter is only 0.041 ± 0.006 dB in the operating bandwidth. The polymer hollow-core fiber coupler boasting an ultra-broadband, short component length, and low loss is very promising in next-generation, high-speed, and large-capacity hollow-core fiber communication systems.

13.
Opt Lett ; 48(4): 888-891, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36790967

RESUMO

Helicity-resolved Raman spectroscopy (HRRS) can effectively distinguish the Raman modes of two-dimensional (2D) layered materials by phonon symmetry. In this paper, we systematically investigated the phonon helicity selection of basal and edge planes of MoS2 bulk by HRRS. We find that the symmetry of the crystal structure changes the helicity selection of the E1g, E1 2g, and A1g modes in the edge plane. The theoretical calculation results confirm that the E1 2g and A1g modes of the basal plane exhibit a perfect helicity exchange, and the helicity selections of the E1 2g and A1g modes of the edge plane are eliminated or weakened. Our study provides references for phonon helicity selection of 2D layered materials represented by MoS2.

14.
Artigo em Inglês | MEDLINE | ID: mdl-37000636

RESUMO

Five aerobic, Gram-stain-negative, non-motile, non-spore-forming, short rod bacteria strains, designated as C3-1-R+6T, C3-2-M9, B3-2-R-7, B3-2-R-21 and C3-2-M2, were isolated from shore soil of LungmuCo Lake in Tibet of China. The 16S rRNA gene sequence comparisons confirmed their affiliation to the genus Parapedobacter of the family Sphingobacteriaceae, and showed that they were most closely related to Parapedobacter lycopersici KACC 18788T with 94.26 % similarities. The average nucleotide identity (ANI), average amino acid identity (AAI) and digital DNA-DNA hybridization (dDDH) values between them and the validly published Parapedobacter species were all below the thresholds for delineating species, supporting that they were novel species of genus Parapedobacter. The ANI, AAI and dDDH values between strains C3-1-R+6T and Parapedobacter lycopersici KACC 18788T were 72, 75, and 18% respectively. Meanwhile, the ANI/AAI and dDDH values between these five isolates were higher than the threshold values, showing that they belonged to the same species of Parapedobacter. According to genome comparison, the novel isolates have some special biosynthetic gene clusters of secondary metabolites including bacteriton, aryl-polyene, lantipeptide and t1pks, which were absent from their most related phylogenetic neighbours P. lycopersici KACC 18788T and P. pyrenivorans CGMCC 1.12195T. The main polar lipids contained phosphatidylethanolamine, one unidentified phospholipid, one unidentified aminolipid, one unidentified glycolipid and five unidentified lipids. The predominant respiratory quinone was MK-7. The major cellular fatty acids were iso-C15 : 0, summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c) and iso-C17 : 0 3-OH. The genome size of strain C3-1-R+6T was 5 984 948 bp, and its genomic DNA G+C content was 46.21 mol%. To sum up, the five strains were identified as a novel species of the genus Parapedobacter, for which the name Parapedobacter tibetensis sp. nov. was proposed. The type strain was C3-1-R+6T (=CGMCC 1.19194T=KCTC 92150T).


Assuntos
Ácidos Graxos , Solo , Ácidos Graxos/química , Tibet , Filogenia , RNA Ribossômico 16S/genética , Lagos , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Composição de Bases , Análise de Sequência de DNA , China
15.
Eur Radiol ; 33(11): 7934-7941, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37284867

RESUMO

OBJECTIVE: To distinguish geniculate ganglion venous malformation (GGVM) from schwannoma (GGS) by using high-resolution CT (HRCT), routine MRI, and dynamic T1-weighted imaging (T1WI) characteristics. METHODS: Surgically confirmed GGVMs and GGSs between 2016 and 2021 were retrospectively included. Preoperative HRCT, routine MR, and dynamic T1WI were performed on all patients. Clinical data, imaging characteristics including lesion size, involvement of facial nerve (FN), signal intensity, enhancement pattern on dynamic T1WI, and bone destruction on HRCT were evaluated. Logistic regression model was developed to identify independent factors for GGVMs, and the diagnostic performance was accessed by receiving operative curve (ROC) analysis. Histological characteristics were explored for both GGVMs and GGSs. RESULTS: Twenty GGVMs and 23 GGSs with mean age of 31 were included. On dynamic T1WI, 18 GGVMs (18/20) showed "pattern A" enhancement (a progressive filling enhancement), while all 23 GGSs showed "pattern B" enhancement (a gradual whole-lesion enhancement) (p < 0.001). Thirteen GGVMs (13/20) showed the "honeycomb" sign whereas all GGS (23/23) showed extensive bone changes on HRCT (p < 0.001). Lesion size, involvement of FN segment, signal intensity on non-contrast T1WI and T2-weighted imaging (T2WI), and homogeneity on enhanced T1WI were obviously differed between two lesions (p < 0.001, p = 0.002, p < 0.001, p = 0.01, p = 0.02, respectively). Regression model showed the "honeycomb" sign and "pattern A" enhancement were independent risk factors. Histologically, GGVM was characterized by interwoven dilated and tortuous veins, while GGS was characterized by abundant spindle cells with dense arterioles or capillaries. CONCLUSIONS: The "honeycomb" sign on HRCT and "pattern A" enhancement on dynamic T1WI are the most promising imaging characteristics for differentiating GGVM from GGS. CLINICAL RELEVANCE STATEMENT: The characteristic sign and enhancement pattern on HRCT and dynamic T1-weighted imaging allow preoperative differentiation of geniculate ganglion venous malformation and schwannoma feasible, which will improve clinical management and benefit patient prognosis. KEY POINTS: • The "honeycomb" sign on HRCT is a reliable finding to differentiate GGVM from GGS. • GGVM typically shows "pattern A" enhancement (focal enhancement of the tumor on early dynamic T1WI, followed by progressive contrast filling of the tumor in the delayed phase), while "pattern B" enhancement (gradual heterogeneous or homogeneous enhancement of the whole lesion) is observed in GGS on dynamic T1WI.


Assuntos
Neurilemoma , Doenças Vasculares , Humanos , Adulto , Gânglio Geniculado/diagnóstico por imagem , Gânglio Geniculado/patologia , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Neurilemoma/diagnóstico por imagem , Neurilemoma/patologia , Diferenciação Celular
16.
Appl Opt ; 62(12): 3225-3232, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37133173

RESUMO

This paper proposes a new portable polarization parametric indirect microscopy imaging without a liquid crystal (LC) retarder. The polarization was modulated by a polarizer automatically rotating when the camera took raw images sequentially. A specific mark tagged the polarization states of each camera's snapshot in the optical illumination path. A computer vision portable polarization parametric indirect microscopy imagrecognition algorithm was developed to retrieve the unknown polarization states from each raw camera image to ensure that the right polarization modulation states were used in the PIMI processing algorithm. The system's performance was verified by obtaining PIMI parametric images of human facial skin. The proposed method avoids the error problem caused by the LC modulator and significantly reduces the whole system's cost.

17.
Nano Lett ; 22(3): 1331-1337, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35073101

RESUMO

Quantum emitters are needed for a myriad of applications ranging from quantum sensing to quantum computing. Hexagonal boron nitride (hBN) quantum emitters are one of the most promising solid-state platforms to date due to their high brightness and stability and the possibility of a spin-photon interface. However, the understanding of the physical origins of the single-photon emitters (SPEs) is still limited. Here we report dense SPEs in hBN across the entire visible spectrum and present evidence that most of these SPEs can be well explained by donor-acceptor pairs (DAPs). On the basis of the DAP transition generation mechanism, we calculated their wavelength fingerprint, matching well with the experimentally observed photoluminescence spectrum. Our work serves as a step forward for the physical understanding of SPEs in hBN and their applications in quantum technologies.

18.
Molecules ; 28(10)2023 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-37241820

RESUMO

Rice protein is a high-quality plant-based protein source that is gluten-free, with high biological value and low allergenicity. However, the low solubility of rice protein not only affects its functional properties such as emulsification, gelling, and water-holding capacity but also greatly limits its applications in the food industry. Therefore, it is crucial to modify and improve the solubility of rice protein. In summary, this article discusses the underlying causes of the low solubility of rice protein, including the presence of high contents of hydrophobic amino acid residues, disulfide bonds, and intermolecular hydrogen bonds. Additionally, it covers the shortcomings of traditional modification methods and the latest compound improvement methods, compares various modification methods, and puts forward the best sustainable, economical, and environmentally friendly method. Finally, this article lists the uses of modified rice protein in dairy, meat, and baked goods, providing a reference for the extensive application of rice protein in the food industry.


Assuntos
Oryza , Solubilidade , Oryza/química , Manipulação de Alimentos/métodos , Proteínas de Plantas , Dieta Livre de Glúten
19.
Molecules ; 28(5)2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36903641

RESUMO

Ultra-high-pressure jet processing (UHPJ) is a new non-thermal processing technique that can be employed for the homogenization and the sterilization of dairy products. However, the effects on dairy products are unknown when using UHPJ for homogenization and sterilization. Thus, this study aimed to investigate the effects of UHPJ on the sensory and curdling properties of skimmed milk and the casein structure in skimmed milk. Skimmed bovine milk was treated with UHPJ using different pressures (100, 150, 200, 250, 300 MPa) and casein was extracted by isoelectric precipitation. Subsequently, the average particle size, Zeta potential, contents of free sulfhydryl and disulfide bonds, secondary structure, and surface micromorphology were all used as evaluation indicators to explore the effects of UHPJ on the structure of casein. The results showed that with an increase of pressure, the free sulfhydryl group content changed irregularly, while the disulfide bond content increased from 1.085 to 3.0944 µmol/g. The content of α-helix and random coil in the casein decreased, while the ß-sheet content increased at 100, 150, 200 MPa pressure. However, treatment with higher pressures of 250 and 300 MPa had the opposite effect. The average particle size of the casein micelles first decreased to 167.47 nm and then increased up to 174.63 nm; the absolute value of Zeta potential decreased from 28.33 to 23.77 mV. Scanning electron microscopy analysis revealed that the casein micelles had fractured into flat, loose, porous structures under pressure instead of into large clusters. After being ultra-high-pressure jet-processed, the sensory properties of skimmed milk and its fermented curd were analyzed concurrently. The results demonstrated that UHPJ could alter the viscosity and color of skimmed milk, shortening curdling time from 4.5 h to 2.67 h, and that the texture of the curd fermented with this skimmed milk could be improved to varying degrees by changing the structure of casein. Thus, UHPJ has a promising application in the manufacture of fermented milk due to its ability to enhance the curdling efficiency of skimmed milk and improve the texture of fermented milk.


Assuntos
Caseínas , Leite , Animais , Leite/química , Caseínas/química , Micelas , Esterilização , Dissulfetos/análise
20.
Int J Comput Dent ; 26(4): 319-330, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36749283

RESUMO

AIM: The aim of the present study was to evaluate the effect of cement gap and drill offset on the marginal and internal fit discrepancies of crowns designed with different tooth preparations. MATERIALS AND METHODS: Five tooth preparations were constructed, and crowns with different cement gaps and drill offsets were obtained. Then, best-fit alignment was performed on the crowns with the corresponding tooth preparations, and the fit discrepancies were expressed by color-coded difference images and root mean square (RMS) values. The RMS values of each group were analyzed by the rank-based Scheirer-Ray-Hare test (α = 0.05). RESULTS: The color segments in the sharp line angles area of the Sharp line angles group changed significantly before and after the drill offset. The cement gap had a significant effect on the marginal, internal, or overall fit discrepancies of the five design groups (P < 0.001), while the drill offset had a significant effect on the marginal fit discrepancies of the Shoulder-lip group and the internal or overall fit discrepancies of the Sharp line angles group (P < 0.001). Additionally, the interaction effect between cement gap and drill offset was significant for the marginal fit discrepancies of the Shoulder-lip group and the internal or overall fit discrepancies of the Sharp line angles group (P < 0.01). CONCLUSIONS: The cement gap and drill offset had a significant adverse effect on the marginal or internal fit discrepancies of the crowns designed with the shoulder-lip and sharp line angles designs. Tooth preparation designs with intense curvature changes such as shoulder-lip and sharp line angles should be avoided clinically.


Assuntos
Coroas , Cimentos Dentários , Humanos , Cimentos de Ionômeros de Vidro , Preparo do Dente , Preparo Prostodôntico do Dente/métodos , Planejamento de Prótese Dentária , Desenho Assistido por Computador , Adaptação Marginal Dentária , Porcelana Dentária
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