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1.
Opt Lett ; 49(10): 2721-2724, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748145

RESUMO

A 2 × 2 switch based on differential effective thermo-optic (TO) coefficients of waveguide supermodes is proposed and experimentally demonstrated as a more compact alternative to Mach-Zehnder interferometer (MZI)-based switches used in coherent photonic matrix processing networks. The total waveguide width of the device is 1.335 µm. Using a novel, to the best of our knowledge, supermode coupler with a wideband 3-dB coupling ratio, the switch was engineered to have on-off extinction ratios (ERs) ranging from 24.1 to 38.9 dB for the two output ports over a 135 nm bandwidth. Insertion losses (ILs) of less than 0.3 and 0.4 dB over the 100 nm bandwidth were measured for bar and cross transmission, respectively. The waveguide width error tolerance is +/-30 nm. The proposed device has the potential to improve the scalability of a programmable coherent mesh for matrix processing by increasing the integration density without sacrificing the overall accuracy or limiting the operational wavelength range of the mesh.

2.
Microbiol Spectr ; 12(3): e0384623, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38299831

RESUMO

Acidovorax citrulli is the main pathogen causing bacterial fruit blotch, which seriously threatens the global watermelon industry. At present, rapid, sensitive, and low-cost detection methods are urgently needed. The established CRISPR/LbCas12a visual detection method can specifically detect A. citrulli and does not cross-react with other pathogenic bacteria such as Erwinia tracheiphila, Pseudomonas syringae, and Xanthomonas campestris. The sensitivity of this method for genomic DNA detection is as low as 0.7 copies/µL, which is higher than conventional PCR and real-time PCR. In addition, this method only takes 2.5 h from DNA extraction to quantitative detection and does not require complex operation and sample treatment. Additionally, the technique was applied to test real watermelon seed samples for A. citrulli, and the results were contrasted with those of real-time fluorescence quantitative PCR and conventional PCR. The high sensitivity and specificity have broad application prospects in the rapid detection of bacterial fruit blotch bacterial pathogens of watermelon.IMPORTANCEBacterial fruit blotch, Acidovorax citrulli, is an important seed-borne bacterial disease of watermelon, melon, and other cucurbits. The lack of rapid, sensitive, and reliable pathogen detection methods has hampered research on fruit spot disease prevention and control. Here, we demonstrate the CRISPR/Cas12a system to analyze aspects of the specificity and sensitivity of A. citrulli and to test actual watermelon seed samples. The results showed that the CRISPR/Cas12a-based free-amplification method for detecting bacterial fruit blotch pathogens of watermelons was specific for A. citrulli target genes and 100-fold more sensitive than conventional PCR with quantitative real-time PCR. This method provides a new technical tool for the detection of A. citrulli.


Assuntos
Citrullus , Comamonadaceae , Citrullus/genética , Citrullus/microbiologia , Frutas/microbiologia , Doenças das Plantas/microbiologia , Comamonadaceae/genética , DNA
3.
World J Clin Cases ; 12(1): 163-168, 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38292635

RESUMO

BACKGROUND: Endophthalmitis occurring in silicone oil-filled eyes is a very rare occurrence, with reported incidence rates ranging between 0.07% and 0.039%. Traditional methods of management of infectious endophthalmitis include the removal of silicone oil, washout of the vitreous cavity, administration of intravitreal antibiotics, and re-injection of silicone oil. CASE SUMMARY: Herein, we report the case of a 39-year-old man with unilateral endophthalmitis after pars plana vitrectomy and silicone oil tamponade. Intravitreal injections of full-dose antibiotics and anterior chamber washout were used to treat the patient. No signs of retinal toxicity were observed during the follow-up period. CONCLUSION: Intravitreal full-dose antibiotic injections and anterior chamber washout are promising alternatives to traditional therapies for endophthalmitis in silicone oil-filled eyes.

4.
Complement Ther Med ; 80: 103013, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38184285

RESUMO

OBJECTIVES: This study aims to investigate the effectiveness of cupping therapy on low back pain (LBP). METHODS: Medline, Embase, Scopus and WANFANG databases were searched for relevant cupping RCTs on low back pain articles up to 2023. A complementary search was manually made on 27 September for update screening. Full-text English and Chinese articles on all ethnic adults with LBP of cupping management were included in this study. Studies looking at acute low back pain only were excluded. Two independent reviewers screened and extracted data, with any disagreement resolved through consensus by a third reviewer. The methodological quality of the included studies was evaluated independently by two reviewers using an adapted tool. Change-from-baseline outcomes were treated as continuous variables and calculated according to the Cochrane Handbook. Data were extracted and pooled into the meta-analysis by Review Manager software (version 5.4, Nordic Cochrane Centre). RESULTS: Eleven trials involving 921 participants were included. Five studies were assessed as being at low risk of bias, and six studies were of acceptable quality. High-quality evidence demonstrated cupping significantly improves pain at 2-8 weeks endpoint intervention (d=1.09, 95% CI: [0.35-1.83], p = 0.004). There was no continuous pain improvement observed at one month (d=0.11, 95% CI: [-1.02-1.23], p = 0.85) and 3-6 months (d=0.39, 95% CI: [-0.09-0.87], p = 0.11). Dry cupping did not improve pain (d=1.06, 95% CI: [-0.34, 2.45], p = 0.14) compared with wet cupping (d=1.5, 95% CI: [0.39-2.6], p = 0.008) at the endpoint intervention. There was no evidence indicating the association between pain reduction and different types of cupping (p = 0.2). Moderate- to low-quality evidence showed that cupping did not reduce chronic low back pain (d=0.74, 95% CI: [-0.67-2.15], p = 0.30) and non-specific chronic low back pain (d=0.27, 95% CI: [-1.69-2.24], p = 0.78) at the endpoint intervention. Cupping on acupoints showed a significant improvement in pain (d=1.29, 95% CI: [0.63-1.94], p < 0.01) compared with the lower back area (d=0.35, 95% CI: [-0.29-0.99], p = 0.29). A potential association between pain reduction and different cupping locations (p = 0.05) was found. Meta-analysis showed a significant effect on pain improvement compared to medication therapy (n = 8; d=1.8 [95% CI: 1.22 - 2.39], p < 0.001) and usual care (n = 5; d=1.07 [95% CI: 0.21- 1.93], p = 0.01). Two studies demonstrated that cupping significantly mediated sensory and emotional pain immediately, after 24 h, and 2 weeks post-intervention (d= 5.49, 95% CI [4.13-6.84], p < 0.001). Moderate evidence suggested that cupping improved disability at the 1-6 months follow-up (d=0.67, 95% CI: [0.06-1.28], p = 0.03). There was no immediate effect observed at the 2-8 weeks endpoint (d=0.40, 95% CI: [-0.51-1.30], p = 0.39). A high degree of heterogeneity was noted in the subgroup analysis (I2 >50%). CONCLUSION: High- to moderate-quality evidence indicates that cupping significantly improves pain and disability. The effectiveness of cupping for LBP varies based on treatment durations, cupping types, treatment locations, and LBP classifications. Cupping demonstrated a superior and sustained effect on pain reduction compared with medication and usual care. The notable heterogeneity among studies raises concerns about the certainty of these findings. Further research should be designed with a standardized cupping manipulation that specifies treatment sessions, frequency, cupping types, and treatment locations. The actual therapeutic effects of cupping could be confirmed by using objective pain assessments. Studies with at least six- to twelve-month follow-ups are needed to investigate the long-term efficacy of cupping in managing LBP. TRIAL REGISTRATION: This systematic review was initially registered on PROSPERO with registration code: CRD42021271245 on 08 September 2021.


Assuntos
Dor Aguda , Ventosaterapia , Dor Lombar , Adulto , Humanos , Viés , Dor Lombar/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
Ecotoxicol Environ Saf ; 252: 114619, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36753967

RESUMO

The development of agriculture and industry has led to a gradual increase in the levels of cadmium (Cd) in the soil, which, due to its high mobility in soil, makes Cd deposition in plants a serious threat to the health of animals and humans. The important role of melatonin (MT) in regulating plant growth and adaptation to environmental stress has become a pertinent research topic, but the mechanisms of action of MT in Cd-stressed Platycladus orientalis seedlings are unclear. Here, we investigated the mitigation mechanism of exogenous MT application on P. orientalis seedlings under Cd stress. Cd stress significantly inhibited the growth of P. orientalis seedlings by disrupting photosynthetic pigments, mineral balance, osmotic balance, and oxidative balance. In contrast, the application of exogenous MT significantly increased the growth parameters of P. orientalis seedlings, reduced Cd accumulation and transfer in the seedlings, increased the content of iron, manganese, zinc, copper, chlorophyll, soluble protein, soluble sugar, and proline, reduced the content of glutathione, increased the activities of superoxide dismutase and peroxidase, and significantly enhanced the expression of antioxidant-related genes (POD, GST, and APX). It also effectively reduced the content of hydrogen peroxide and malondialdehyde to inhibit the production of reactive oxygen species, thus alleviating Cd-induced oxidative stress. In addition, MT significantly upregulated the expression of the ethanol dehydrogenase (ADH) gene, which is effective in removing the acetaldehyde produced by anaerobic respiration in seedlings under stress, thereby reducing the toxic effects on P. orientalis. The results showed that exogenous MT enhanced the tolerance of P. orientalis seedlings to Cd stress by regulating photosynthesis, mineral balance, osmotic balance, and the antioxidant system and that the optimal concentration of MT was 200 µmol·L-1.


Assuntos
Antioxidantes , Melatonina , Humanos , Antioxidantes/metabolismo , Melatonina/farmacologia , Melatonina/metabolismo , Cádmio/metabolismo , Plântula , Estresse Oxidativo , Minerais/metabolismo , Nutrientes , Solo , Peróxido de Hidrogênio/metabolismo
7.
Opt Lett ; 46(17): 4232-4235, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34469982

RESUMO

Extending the optical communication wavelengths to 2 µm can significantly increase data capacity. Silicon photonics, which is a proven device integration technology, has made rapid progress at 2 µm recently. As a fundamental functional element in the photonic design kit, the 3 dB power splitter has been extensively studied in both the 1.55 µm and 2 µm regime. While the device is highly desirable to operate over both wave bands, the large waveguide dispersion in silicon makes it challenging. In this work, we demonstrate an ultra-broadband power splitter on silicon, which has a 0.2 dB bandwidth exceeding 520 nm from 1500 to 2020 nm according to simulations. The beam splitter is realized by a triple tapered Y-junction, and its operational bandwidth is greatly increased by subwavelength grating structure. The device has an ultra-compact footprint of only 3µm×2µm. Due to the limitations on the setup and coupling technique, we measure the device bandwidth in 1.55 µm and 2 µm wave bands. The device insertion loss is measured to be below 0.4 dB from 1500 to 1620 nm and from 1960 to 2020 nm, respectively. According to these results, the proposed device is believed to be capable of operating over a broadband from 1.55 µm and 2 µm wavelengths.

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