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1.
Nature ; 606(7916): 890-895, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35676489

RESUMEN

Majorana zero modes (MZMs) obey non-Abelian statistics and are considered building blocks for constructing topological qubits1,2. Iron-based superconductors with topological bandstructures have emerged as promising hosting materials, because isolated candidate MZMs in the quantum limit have been observed inside the topological vortex cores3-9. However, these materials suffer from issues related to alloying induced disorder, uncontrolled vortex lattices10-13 and a low yield of topological vortices5-8. Here we report the formation of an ordered and tunable MZM lattice in naturally strained stoichiometric LiFeAs by scanning tunnelling microscopy/spectroscopy. We observe biaxial charge density wave (CDW) stripes along the Fe-Fe and As-As directions in the strained regions. The vortices are pinned on the CDW stripes in the As-As direction and form an ordered lattice. We detect that more than 90 per cent of the vortices are topological and possess the characteristics of isolated MZMs at the vortex centre, forming an ordered MZM lattice with the density and the geometry tunable by an external magnetic field. Notably, with decreasing the spacing of neighbouring vortices, the MZMs start to couple with each other. Our findings provide a pathway towards tunable and ordered MZM lattices as a platform for future topological quantum computation.

2.
Drug Resist Updat ; 73: 101062, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38330827

RESUMEN

Multidrug resistance protein 7 (MRP7), also known as ATP-binding cassette (ABC) transporter subfamily C10 (ABCC10), is an ABC transporter that was first identified in 2001. ABCC10/MRP7 is a 171 kDa protein located on the basolateral membrane of cells. ABCC10/MRP7 consists of three transmembrane domains and two nucleotide binding domains. It mediates multidrug resistance of tumor cells to a variety of anticancer drugs by increasing drug efflux and results in reducing intracellular drug accumulation. The transport substrates of ABCC10/MRP7 include antineoplastic drugs such as taxanes, vinca alkaloids, and epothilone B, as well as endobiotics such as leukotriene C4 (LTC4) and estradiol 17 ß-D-glucuronide. A variety of ABCC10/MRP7 inhibitors, including cepharanthine, imatinib, erlotinib, tariquidar, and sildenafil, can reverse ABCC10/MRP7-mediated MDR. Additionally, the presence or absence of ABCC10/MRP7 is also closely related to renal tubular dysfunction, obesity, and other diseases. In this review, we discuss: 1) Structure and functions of ABCC10/MRP7; 2) Known substrates and inhibitors of ABCC10/MRP7 and their potential therapeutic applications in cancer; and 3) Role of ABCC10/MRP7 in non-cancerous diseases.


Asunto(s)
Antineoplásicos , Neoplasias , Humanos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Resistencia a Antineoplásicos/genética , Resistencia a Múltiples Medicamentos/genética , Mesilato de Imatinib/farmacología , Neoplasias/tratamiento farmacológico , Neoplasias/genética
3.
Genome Res ; 31(7): 1150-1158, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34155038

RESUMEN

Protein-truncating variants (PTVs) have important impacts on phenotype diversity and disease. However, their population genetics characteristics in more globally diverse populations are not well defined. Here, we describe patterns of PTVs in 1320 genes sequenced in 10,539 healthy controls and 9434 patients with psoriasis, all of Han Chinese ancestry. We identify 8720 PTVs, of which 77% are novel, and estimate 88% of all PTVs are deleterious and subject to purifying selection. Furthermore, we show that individuals with psoriasis have a significantly higher burden of PTVs compared to controls (P = 0.02). Finally, we identified 18 PTVs in 14 genes with unusually high levels of population differentiation, consistent with the action of local adaptation. Our study provides insights into patterns and consequences of PTVs.

4.
Opt Lett ; 49(10): 2821-2824, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38748170

RESUMEN

Waveguide Bragg grating (WBG) blood glucose sensing, as a biological sensing technology with broad application prospects, plays an important role in the fields of health management and medical treatment. In this work, a polymer-based cascaded WBG is applied to glucose detection. We investigated photonic devices with two different grating structures cascaded-a crossed grating and a bilateral grating-and analyzed the effects of the crossed grating period, bilateral grating period, and number of grating periods on the sensing performance of the glucose sensor. Finally, the spectral reflectance characteristics, response time, and sensing specificity of the cascaded WBG were evaluated. The experimental results showed that the glucose sensor has a sensitivity of 175 nm/RIU in a glucose concentration range of 0-2 mg/ml and has the advantages of high integration, a narrow bandwidth, and low cost.


Asunto(s)
Glucemia , Polímeros , Polímeros/química , Glucemia/análisis , Técnicas Biosensibles/instrumentación
5.
Cancer Cell Int ; 24(1): 176, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38769521

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) represents one of the most significant causes of mortality due to cancer-related deaths. It has been previously reported that the TGF-ß signaling pathway may be associated with tumor progression. However, the relationship between TGF-ß signaling pathway and HCC remains to be further elucidated. The objective of our research was to investigate the impact of TGF-ß signaling pathway on HCC progression as well as the potential regulatory mechanism involved. METHODS: We conducted a series of bioinformatics analyses to screen and filter the most relevant hub genes associated with HCC. E. coli was utilized to express recombinant protein, and the Ni-NTA column was employed for purification of the target protein. Liquid liquid phase separation (LLPS) of protein in vitro, and fluorescent recovery after photobleaching (FRAP) were utilized to verify whether the target proteins had the ability to drive force LLPS. Western blot and quantitative real-time polymerase chain reaction (qPCR) were utilized to assess gene expression levels. Transcription factor binding sites of DNA were identified by chromatin immunoprecipitation (CHIP) qPCR. Flow cytometry was employed to examine cell apoptosis. Knockdown of target genes was achieved through shRNA. Cell Counting Kit-8 (CCK-8), colony formation assays, and nude mice tumor transplantation were utilized to test cell proliferation ability in vitro and in vivo. RESULTS: We found that Smad2/3/4 complex could regulate tyrosine aminotransferase (TAT) expression, and this regulation could relate to LLPS. CHIP qPCR results showed that the key targeted DNA binding site of Smad2/3/4 complex in TAT promoter region is -1032 to -1182. In addition. CCK-8, colony formation, and nude mice tumor transplantation assays showed that Smad2/3/4 complex could repress cell proliferation through TAT. Flow cytometry assay results showed that Smad2/3/4 complex could increase the apoptosis of hepatoma cells. Western blot results showed that Smad2/3/4 complex would active caspase-9 through TAT, which uncovered the mechanism of Smad2/3/4 complex inducing hepatoma cell apoptosis. CONCLUSION: This study proved that Smad2/3/4 complex could undergo LLPS to active TAT transcription, then active caspase-9 to induce hepatoma cell apoptosis in inhibiting HCC progress. The research further elucidate the relationship between TGF-ß signaling pathway and HCC, which contributes to discover the mechanism of HCC development.

6.
BMC Cardiovasc Disord ; 24(1): 354, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38992615

RESUMEN

BACKGROUND: Hyperlipidemia damages vascular wall and serves as a foundation for diseases such as atherosclerosis, hypertension and stiffness. The NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome is implicated in vascular dysfunction associated with hyperlipidemia-induced vascular injury. Sodium tanshinone IIA sulfonate (STS), a well-established cardiovascular protective drug with recognized anti-inflammatory, antioxidant, and vasodilatory properties, is yet to be thoroughly investigated for its impact on vascular relaxant imbalance induced by hyperlipidemia. METHODS: In this study, we treated ApoE-knockout (ApoE-/-) mouse with STS and assessed the activation of the NLRP3 inflammasome, expression of MMP2/9, integrity of elastic fibers, and vascular constriction and relaxation. RESULTS: Our findings reveal that STS intervention effectively preserves elastic fibers, significantly restores aortic relaxation function in ApoE-/- mice, and reduces their excessive constriction. Furthermore, STS inhibits the phosphorylation of spleen tyrosine kinase (SYK), suppresses NLRP3 inflammasome activation, and reduces MMP2/9 expression. CONCLUSIONS: These results demonstrate that STS protects vascular relaxation against hyperlipidemia-induced damage through modulation of the SYK-NLRP3 inflammasome-MMP2/9 pathway. This research provides novel insights into the mechanisms underlying vascular relaxation impairment in a hyperlipidemic environment and uncovers a unique mechanism by which STS preserves vascular relaxation, offering valuable foundational research evidence for its clinical application in promoting vascular health.


Asunto(s)
Modelos Animales de Enfermedad , Inflamasomas , Metaloproteinasa 2 de la Matriz , Metaloproteinasa 9 de la Matriz , Ratones Endogámicos C57BL , Ratones Noqueados para ApoE , Proteína con Dominio Pirina 3 de la Familia NLR , Fenantrenos , Transducción de Señal , Quinasa Syk , Vasodilatación , Animales , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Inflamasomas/metabolismo , Quinasa Syk/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Fenantrenos/farmacología , Masculino , Metaloproteinasa 9 de la Matriz/metabolismo , Vasodilatación/efectos de los fármacos , Hiperlipidemias/tratamiento farmacológico , Hiperlipidemias/fisiopatología , Vasodilatadores/farmacología , Fosforilación , Ratones , Aorta/efectos de los fármacos , Aorta/fisiopatología , Aorta/metabolismo , Aorta/enzimología , Apolipoproteínas E
7.
Environ Res ; 250: 118520, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38401683

RESUMEN

The sedentary and less active lifestyle of modern college students has a significant impact on the physical and mental well-being of the college community. Campus Green Spaces (GSs) are crucial in promoting physical activity and improving students' health. However, previous research has focused on evaluating campuses as a whole, without considering the diverse spatial scenarios within the campus environment. Accordingly, this study focused on the young people's residential scenario in university and constructed a framework including a comprehensive set of objective and subjective GSs exposure metrics. A systematic, objective exposure assessment framework ranging from 2D (GSs areas), and 2.5D (GSs visibility) to 3D (GSs volume) was innovatively developed using spatial analysis, deep learning technology, and unmanned aerial vehicle (UAV) measurement technology. Subjective exposure metrics incorporated GSs visiting frequency, GSs visiting duration, and GSs perceived quality. Our cross-sectional study was based on 820 university students in Nanjing, China. Subjective measures of GSs exposure, physical activity, and health status were obtained through self-reported questionnaires. The Generalized Linear Model (GLM) was used to evaluate the associations between GSs exposure, physical activity, and perceived health. Physical activity and social cohesion were considered as mediators, and path analysis based on Structural Equation Modeling (SEM) was used to disentangle the mechanisms linking GSs exposure to the health status of college students. We found that (1) 2D indicator suggested significant associations with health in the 100m buffer, and the potential underlying mechanisms were: GSs area → Physical activity → Social cohesion → Physical health → Mental health; GSs area → Physical activity → Social cohesion → Mental health. (2) Subjective GSs exposure indicators were more relevant in illustrating exposure-response relationships than objective ones. This study can clarify the complex nexus and mechanisms between campus GSs, physical activity, and health, and provide a practical reference for health-oriented campus GSs planning.


Asunto(s)
Ejercicio Físico , Estudiantes , Humanos , Estudiantes/psicología , Masculino , Adulto Joven , Femenino , Universidades , Estudios Transversales , China , Adolescente , Estado de Salud
8.
Clin Exp Nephrol ; 28(1): 59-66, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37713045

RESUMEN

BACKGROUND: This study aimed to externally validate the pediatric International IgA Nephropathy (IgAN) Prediction Tool updated from the adult IgAN Prediction Tool. METHODS: 439 children with biopsy-confirmed idiopathic IgAN were enrolled in this external validation study. The primary outcome was a 30% decline in eGFR or end-stage kidney disease. We evaluated the discrimination using Harrell's C-index, the receiver operating characteristic (ROC) curve, and Kaplan-Meier curves for four risk groups (< 16th [low risk], ∼16 to < 50th [intermediate risk], ∼50 to < 84th [high risk], and ≥ 84th percentiles [highest risk] of linear predictor). Calibration was assessed using calibration plots. RESULTS: The median follow-up time of the 439 patients was 4.5 (2.7-6.8) years, and 27 patients reached the primary outcome. Compared with the reported cohorts, our cohort was more contemporary, with milder proteinuria at biopsy, and had lower proportions of S1 and T1 lesions. Harrell's C-index and area under the ROC curve at 5 years were < 0.7 for both the models with and without race. The Kaplan-Meier curves of the risk groups were not well separated for the two models, only separated completely between the highest-risk group and the others for the model without race. The two models generally overestimated the risk of the primary outcome, CONCLUSION: The model without race could accurately distinguish the highest-risk patients from patients with low, intermediate, and high risk for kidney progression. Discrimination and calibration for the full model with or without race were unsatisfactory in this contemporary cohort in central China.


Asunto(s)
Glomerulonefritis por IGA , Fallo Renal Crónico , Adulto , Humanos , Niño , Glomerulonefritis por IGA/diagnóstico , Glomerulonefritis por IGA/patología , Riñón/patología , Fallo Renal Crónico/patología , Factores de Riesgo , Proteinuria/patología , Progresión de la Enfermedad , Estudios Retrospectivos , Tasa de Filtración Glomerular
9.
Arch Toxicol ; 98(3): 709-734, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38182913

RESUMEN

With the rapid development of new generations of antitumor therapies, the average survival time of cancer patients is expected to be continuously prolonged. However, these therapies often lead to cardiotoxicity, resulting in a growing number of tumor survivors with cardiovascular disease. Therefore, a new interdisciplinary subspecialty called "cardio-oncology" has emerged, aiming to detect and treat cardiovascular diseases associated with tumors and antitumor therapies. Recent studies have highlighted the role of ferroptosis in both cardiovascular and neoplastic diseases. The balance between intracellular oxidative stress and antioxidant defense is crucial in regulating ferroptosis. Tumor cells can evade ferroptosis by upregulating multiple antioxidant defense pathways, while many antitumor therapies rely on downregulating antioxidant defense and promoting ferroptosis in cancer cells. Unfortunately, these ferroptosis-inducing antitumor therapies often lack tissue specificity and can also cause injury to the heart, resulting in ferroptosis-induced cardiotoxicity. A range of cardioprotective agents exert cardioprotective effects by inhibiting ferroptosis. However, these cardioprotective agents might diminish the efficacy of antitumor treatment due to their antiferroptotic effects. Most current research on ferroptosis only focuses on either tumor treatment or heart protection but rarely considers both in concert. Therefore, further research is needed to study how to protect the heart during antitumor therapies by regulating ferroptosis. In this review, we summarized the role of ferroptosis in the treatment of neoplastic diseases and cardiovascular diseases and also attempted to propose further research directions for ferroptosis in the field of cardio-oncology.


Asunto(s)
Enfermedades Cardiovasculares , Ferroptosis , Humanos , Antioxidantes , Cardiooncología , Cardiotónicos , Cardiotoxicidad , Enfermedades Cardiovasculares/inducido químicamente
10.
Artículo en Inglés | MEDLINE | ID: mdl-38466057

RESUMEN

Objective: To assess the influence of high-quality nursing during visual electrophysiology examinations on both nursing outcomes and stress levels. Methods: A total of 80 patients who underwent visual electrophysiology examinations in the hospital from January 2021 to January 2022 were included as study subjects and randomized into two groups using random allocation. This random assignment ensures that each patient has an equal chance of being assigned to either group, minimizing the effects of confounding variables and evenly distributing potential bias. The control group received conventional nursing care, while the study group received quality nursing care, with 40 patients in each group. Patients in both groups were compared regarding nursing impact, occurrence of adverse reactions, pain level, and stress status. Results: In the study group, 39 patients exhibited high levels of cooperation, while 1 demonstrated a low degree of cooperation. Conversely, in the control group, 36 subjects were highly cooperative, but 6 displayed a low degree of cooperation. The cooperation rate was significantly higher in the study group compared to the control group (97.5% vs. 85.0%, χ² = 3.914, P = .048). SAS scores and SDS scores after treatment were observed to be lower in the study group compared to those in the control group (P < .05). The increase in scores within the study group was notably less than that observed in the control group (P < .05). The results indicate that 38 patients in the study group reported satisfaction, while 31 in the control group expressed satisfaction. The nursing satisfaction rate was significantly higher in the study group than in the control group (P < .05). Conclusions: Quality nursing care during visual electrophysiology examinations proves to be highly effective in enhancing patient compliance, fostering a higher rate of patient cooperation, and mitigating patient stress. Furthermore, it contributes to the improvement of patient satisfaction with nursing care, ultimately elevating the overall healthcare relationship.

11.
Nano Lett ; 23(10): 4541-4547, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37162755

RESUMEN

The controlled manipulation of Abrikosov vortices is essential for both fundamental science and logical applications. However, achieving nanoscale manipulation of vortices while simultaneously measuring the local density of states within them remains challenging. Here, we demonstrate the manipulation of Abrikosov vortices by moving the pinning center, namely one-dimensional wrinkles, on the terminal layers of Fe(Te,Se) and LiFeAs, by utilizing low-temperature scanning tunneling microscopy/spectroscopy (STM/S). The wrinkles trap the Abrikosov vortices induced by the external magnetic field. In some of the wrinkle-pinned vortices, robust zero-bias conductance peaks are observed. We tailor the wrinkle into short pieces and manipulate the wrinkles by using an STM tip. Strikingly, we demonstrate that the pinned vortices move together with these wrinkles even at high magnetic field up to 6 T. Our results provide a universal and effective routine for manipulating wrinkle-pinned vortices and simultaneously measuring the local density of states on the iron-based superconductor surfaces.

12.
Heart Lung Circ ; 33(4): 486-492, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38423849

RESUMEN

AIM: Angiotensin receptor blockers (ARBs) have been shown to inhibit restenosis in vitro and in vivo, but the evidence found in humans is inconsistent. This study aimed to evaluate the effectiveness of ARBs in preventing in-stent restenosis after percutaneous coronary intervention (PCI). METHOD: Databases including the Cochrane Library, MEDLINE, Web of Science, EMBASE, and CNKI were searched to collect randomised controlled trials on ARBs inhibiting restenosis that were published before October 2022. A total of 1,056 patients enrolled in eight trials were included in the study. RESULTS: The ARBs group showed lower target lesion revascularisation than the control group (RR 0.54; 95% CI 0.34-0.86; p=0.01), but the restenosis incidence between these two groups was not statistically significant (RR 0.85; 95% CI 0.65-1.11; p>0.05). CONCLUSION: This study found that ARBs might have a potential effect on reducing target lesion revascularisation after PCI in coronary heart disease patients but has no impact on angiographic restenosis.


Asunto(s)
Antagonistas de Receptores de Angiotensina , Reestenosis Coronaria , Intervención Coronaria Percutánea , Humanos , Reestenosis Coronaria/prevención & control , Antagonistas de Receptores de Angiotensina/uso terapéutico , Intervención Coronaria Percutánea/métodos , Stents/efectos adversos , Oclusión de Injerto Vascular/prevención & control
13.
J Synchrotron Radiat ; 30(Pt 6): 1054-1063, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37860938

RESUMEN

Recently, a novel approach has been proposed to produce ultrashort, fully coherent high-repetition-rate EUV and X-ray radiation by combining an energy recovery linac (ERL) with the angular-dispersion-induced microbunching methodology. It is critical to maintain microbunching when the beam passes through bending magnets between the undulators, which results in difficulties supporting multiple beamlines. In this paper, the design of a multiplexed emitting system consisting of multi-bend achromats, matching sections and radiators to facilitate the multi-beamline operation is presented. Theoretical analysis and numerical simulations have been carried out and the results show that the microbunching and beam quality can be well maintained after four times of bending. Five radiation pulses with a central wavelength of 13.5 nm and peak power at the MW level have been produced by the same electron beam via this multiplexed emitting system. The proposed method holds potential in the multi-beamline operation of ERL- or storage-ring-based coherent light sources.

14.
J Transl Med ; 21(1): 341, 2023 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-37217923

RESUMEN

BACKGROUND: Immunocheckpoint inhibitors (ICIs) have been widely used in the clinical treatment of lung cancer. Although clinical studies and trials have shown that patients can benefit significantly after PD-1/PD-L1 blocking therapy, less than 20% of patients can benefit from ICIs therapy due to tumor heterogeneity and the complexity of immune microenvironment. Several recent studies have explored the immunosuppression of PD-L1 expression and activity by post-translational regulation. Our published articles demonstrate that ISG15 inhibits lung adenocarcinoma progression. Whether ISG15 can enhance the efficacy of ICIs by modulating PD-L1 remains unknown. METHODS: The relationship between ISG15 and lymphocyte infiltration was identified by IHC. The effects of ISG15 on tumor cells and T lymphocytes were assessed using RT-qPCR and Western Blot and in vivo experiments. The underlying mechanism of PD-L1 post-translational modification by ISG15 was revealed by Western blot, RT-qPCR, flow cytometry, and Co-IP. Finally, we performed validation in C57 mice as well as in lung adenocarcinoma tissues. RESULTS: ISG15 promotes the infiltration of CD4+ T lymphocytes. In vivo and in vitro experiments demonstrated that ISG15 induces CD4+ T cell proliferation and invalidity and immune responses against tumors. Mechanistically, we demonstrated that the ubiquitination-like modifying effect of ISG15 on PD-L1 increased the modification of K48-linked ubiquitin chains thus increasing the degradation rate of glycosylated PD-L1 targeting proteasomal pathway. The expression of ISG15 and PD-L1 was negatively correlated in NSCLC tissues. In addition, reduced accumulation of PD-L1 by ISG15 in mice also increased splenic lymphocyte infiltration as well as promoted cytotoxic T cell infiltration in the tumor microenvironment, thereby enhancing anti-tumor immunity. CONCLUSIONS: The ubiquitination modification of PD-L1 by ISG15 increases K48-linked ubiquitin chain modification, thereby increasing the degradation rate of glycosylated PD-L1-targeted proteasome pathway. More importantly, ISG15 enhanced the sensitivity to immunosuppressive therapy. Our study shows that ISG15, as a post-translational modifier of PD-L1, reduces the stability of PD-L1 and may be a potential therapeutic target for cancer immunotherapy.


Asunto(s)
Adenocarcinoma del Pulmón , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Animales , Ratones , Antígeno B7-H1/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Línea Celular Tumoral , Neoplasias Pulmonares/patología , Microambiente Tumoral , Ubiquitinas
15.
Opt Express ; 31(8): 12072-12082, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37157374

RESUMEN

Electro-optic (EO) modulators are typically made of inorganic materials such as lithium niobate; the replacement of these modulators with organic EO materials is a promising alternative due to their lower half-wave voltage (Vπ), ease of handling, and relatively low cost. We propose the design and fabrication of a push-pull polymer electro-optic modulator with voltage-length parameters (VπL) of 1.28 V·cm. The device uses a Mach-Zehnder structure and is made of a second-order nonlinear optical host-guest polymer composed of a CLD-1 chromophore and PMMA polymer. The experimental results show that the loss is 1.7 dB, Vπ drops to 1.6 V, and the modulation depth is 0.637 dB at 1550 nm. The results of a preliminary study show that the device is capable of efficiently detecting electrocardiogram (ECG) signals with performance on par with that of commercial ECG devices.

16.
Opt Express ; 31(20): 33535-33547, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37859133

RESUMEN

Flexible pressure sensors provide a promising platform for artificial smart skins, and photonic devices provide a new technique to fabricate pressure sensors. Here, we present a flexible waveguide-based optical pressure sensor based on a microring structure. The waveguide-based optical pressure sensor is based on a five-cascade microring array structure with a size of 1500 µm × 500 µm and uses the change in output power to linearly characterize the change in pressure acting on the device. The results show that the device has a sensing range of 0-60 kPa with a sensitivity of 23.14 µW/kPa, as well as the ability to detect pulse signals, swallowing, hand gestures, etc. The waveguide-based pressure sensors offer the advantages of good output linearity, high integration density and easy-to-build arrays.

17.
Opt Express ; 31(20): 32458-32467, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37859048

RESUMEN

Polymer materials have the advantages of a low Young's modulus and low-cost preparation process. In this paper, a polymer-based optical waveguide pressure sensor based on a Bragg structure is proposed. The change in the Bragg wavelength in the output spectrum of the waveguide Bragg grating (WBG) is used to linearly characterize the change in pressure acting on the device. The polymer-based WBG was developed through a polymer film preparation process, and the experimental results show that the output signal of the device has a sensitivity of 1.275 nm/kPa with a measurement range of 0-12 kPa and an accuracy of 1 kPa. The experimental results indicate that the device already perfectly responds to a pulse signal. It has significant potential application value in medical diagnostics and health testing, such as blood pressure monitoring, sleep quality monitoring, and tactile sensing.

18.
Opt Lett ; 48(10): 2527-2530, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-37186699

RESUMEN

Recently developed image-free sensing techniques have achieved remarkable performance in various vision tasks. However, existing image-free methods still cannot simultaneously obtain the category, location, and size information of all objects. In this Letter, we report a novel image-free single-pixel object detection (SPOD) technique. SPOD enables efficient and robust multi-object detection directly from a small number of measurements, eliminating the requirement for complicated image reconstruction. Different from the conventional full-size pattern sampling method, the reported small-size optimized pattern sampling method achieves higher image-free sensing accuracy with fewer pattern parameters (∼1 order of magnitude). Moreover, instead of simply stacking CNN layers, we design the SPOD network based on the transformer architecture. It can better model global features and reinforce the network's attention to the targets in the scene, thus improving the object detection performance. We demonstrate the effectiveness of SPOD on the Voc dataset, which achieves a detection accuracy of 82.41% mAP at a sampling rate of 5% with a refresh rate of 63 f.p.s.

19.
Langmuir ; 39(11): 4037-4048, 2023 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-36907993

RESUMEN

By directly harming cancer cells, radiotherapy (RT) is a crucial therapeutic approach for the treatment of cancers. However, the efficacy of RT is reduced by the limited accumulation and short retention time of the radiosensitizer in the tumor. Herein, we developed hypoxia-triggered in situ aggregation of nanogapped gold nanospheres (AuNNP@PAA/NIC NPs) within the tumor, resulting in second near-infrared window (NIR-II) photoacoustic (PA) imaging and enhanced radiosensitization. AuNNP@PAA/NIC NPs demonstrated increased accumulation and retention in hypoxic tumors, mainly due to the hypoxia-triggered aggregation. After aggregation of AuNNP@PAA/NIC NPs, the absorption of the system extended from visible light to NIR-II light owing to the plasmon coupling effects between adjacent nanoparticles. Compared to the normoxic tumor, the PA intensity at 1200 nm in the hypoxic tumor increased from 0.42 to 1.88 at 24 h postintravenous injection of AuNNP@PAA/NIC NPs, leading to an increase of 4.5 times. This indicated that the hypoxic microenvironment in the tumor successfully triggered the in situ aggregation of AuNNP@PAA/NIC NPs. The in vivo radiotherapeutic effect demonstrated that this hypoxia-triggered in situ aggregation of radiosensitizers significantly enhanced radiosensitization and thus resulted in superior cancer radiotherapeutic outcomes.


Asunto(s)
Nanopartículas del Metal , Nanopartículas , Neoplasias , Técnicas Fotoacústicas , Fármacos Sensibilizantes a Radiaciones , Humanos , Oro , Técnicas Fotoacústicas/métodos , Neoplasias/diagnóstico por imagen , Neoplasias/radioterapia , Neoplasias/patología , Fármacos Sensibilizantes a Radiaciones/farmacología , Hipoxia , Línea Celular Tumoral , Microambiente Tumoral
20.
Environ Sci Technol ; 57(1): 297-309, 2023 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-36576880

RESUMEN

To explore the effect of different types of dissolved organic matter (DOM) decomposition on nutrient cycling pathways and the microbial loop, four lakes with different DOM sources were investigated monthly. In Lake Tangxun, Dolichospermum decay released highly labile dissolved organic nitrogen into the water column. This induced bacterial organic nitrogen decomposition, as indicated by the increased abundance of gltB, gltD, gdh, and glnA as well as aminopeptidase activity. Genes associated with dissimilatory nitrate reduction to ammonium further fueled ammonium accumulation, driving Microcystis blooms in the summer. In Lake Zhiyin, fish bait deposits (high nitrogen, similar to Dolichospermum detritus) also caused Microcystis blooms. Detritus from Microcystis decomposition then produced high levels of labile dissolved organic phosphorus, inducing phosphatase activity and increasing soluble reactive phosphorus concentrations from September to April in Lakes Tangxun and Zhiyin. The high refractory DOM from macrophytes in Lake Houguan led to insufficient nutrient availability, leading to nutrient mutualism between algae and bacteria. The high levels of labile dissolved organic carbon from terrestrial detritus in Lake Yandong increased bacterial biomass and production, resulting in low chlorophyll content due to the competitive relationship between algal and bacterial nutrient requirements. Therefore, different DOM compositions induce unique connections among available nutrients, algae, and bacteria in the microbial loop.


Asunto(s)
Compuestos de Amonio , Cianobacterias , Lagos/química , Lagos/microbiología , Materia Orgánica Disuelta , Nitrógeno/análisis , China
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