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2.
Biomicrofluidics ; 18(2): 021301, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38566823

RESUMO

Fluid manipulation is an important foundation of microfluidic technology. Various methods and devices have been developed for fluid control, such as electrowetting-on-dielectric-based digital microfluidic platforms, microfluidic pumps, and pneumatic valves. These devices enable precise manipulation of small volumes of fluids. However, their complexity and high cost limit the commercialization and widespread adoption of microfluidic technology. Shape memory polymers as smart materials can adjust their shape in response to external stimuli. By integrating shape memory polymers into microfluidic chips, new possibilities for expanding the application areas of microfluidic technology emerge. These shape memory polymers can serve as actuators or regulators to drive or control fluid flow in microfluidic systems, offering innovative approaches for fluid manipulation. Due to their unique properties, shape memory polymers provide a new solution for the construction of intelligent and automated microfluidic systems. Shape memory microfluidic chips are expected to be one of the future directions in the development of microfluidic technology. This article offers a summary of recent research achievements in the field of shape memory microfluidic chips for fluid and droplet manipulation and provides insights into the future development direction of shape memory microfluidic devices.

3.
Plant Dis ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38568791

RESUMO

Chrysanthemum (Chrysanthemum morifolium cv. Fubaiju) is used as medicinal herb (Chen et al. 2020). In October 2021, a leaf spot disease was observed on leaves of C. morifolium in Huanggang, Hubei province. Disease incidence was approximately 40%. Leaf lesions manifested as necrotic spots, coalesced, and expanded to form brown-black spots, leading to wilting of the leaves. On stems, the lesions manifested as dark brown necrotic spots. To identify the pathogen, 29 pieces (5 × 5 mm) from lesion margins were surface sterilized in 1% NaOCl and rinsed three times with sterile water. The pieces were transferred onto potato dextrose agar (PDA) for incubation at 25℃ for 3 d in the dark. Fifteen fungal colonies were successfully isolated. The colony morphology with flat wavy edge, sparse aerial mycelia, and surface olivaceous black were observed at 7 days post incubation. Subglobular pycnidia were brown with a short beak, and pycnidia diameters were thick (212 to 265 × 189 to 363 µm, n = 20). Ovoid conidia were aseptate and hyaline, conidia diameters were thick (4.0 to 9.8 × 1.8 to 4.7 µm, n = 100). The morphological characters of these isolates were consistent with those of Stagonosporopsis chrysanthemi (Zhao et al. 2021). Pure culture of representative HGNU2021-18 isolated from the diseased leaves subjected to molecular identification. Sequences of the rDNA internal transcribed spacer (ITS) region, 28S large subunit ribosomal RNA (LSU), ß-tubulin (TUB2), actin (ACT), and partial RNA polymerase II largest subunit (RPB2) genes were amplified from genomic DNA of isolate HGNU2021-18 using the following primer pairs: ITS1/ITS4 (White et al. 1990), LR0R/LR5 (Rehner et al. 1994), Btub2Fd/Btub4Rd (Woudenberg et al. 2009), ACT512F/ACT783R (Carbone et al.1999), and RPB2-5F2 (Sung et al. 2007)/fRPB2-7cR (Liu et al. 1999), respectively. The PCR products were purified and then sequenced by Sangon Biotech (China). Nucleotide sequences of ITS (544 bp, OM346748), LSU (905 bp, OM758418), TUB2 (563 bp, OM945724), ACT (294 bp, OM793715), and RPB2 (957 bp, OM793716) amplified from the isolate HGNU2021-18 were subjected to BLASTn analysis. The results showed that ITS, LSU, TUB2, ACT, and RPB2 shared 100.00%, 99.45%, 99.20%, 100.00%, and 100.00% sequence identity to the five published sequences (MW810272.1, MH869953.1, MW815129.1, JN251973.1, and MT018012.1, respectively) of the S. chrysanthemi isolate CBS 500.63. Phylogenetic analysis of the multilocus sequences of ITS, LSU, RPB2, ACT, and TUB2 belonging to different Stagonosporopsis species was performed in MEGA 7.0 (Chen et al. 2015). Isolate HGNU2021-18 was placed in a clade with S. chrysanthemi with 99% bootstrap support. Thus, the results of morphological and molecular analyses indicated that the disease symptoms on chrysanthemum plants were caused by S. chrysanthemi. Under conditions of 25°C and 85% relative humidity, pathogenicity test was performed on 2-month-old healthy plants using isolate HGNU2021-18. The leaves were inoculated with 5 mm diameter mycelial plugs or with sterile agar plugs (control). Six plants were used in each treatment. Disease symptoms were observed on treated plants at 2 weeks post inoculation which were those previously observed in the field, while the control plants remained symptomless. The pathogen was re-isolated from the diseased plants, and S. chrysanthemi was confirmed as the causal pathogen. This is the first report of S. chrysanthemi causing stem and foliage blight of chrysanthemum in China.

4.
Opt Express ; 32(7): 12601-12608, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38571078

RESUMO

Silicon avalanche photodiode (APD) single-photon detectors in space are continuously affected by radiation, which gradually degrades their dark count performance. From August 2016 to June 2023, we conducted approximately seven years (2507 days) of in-orbit monitoring of the dark count performance of APD single-photon detectors on the Micius Quantum Science Experimental Satellite. The results showed that due to radiation effects, the dark count growth rate was approximately 6.79 cps/day @ -24 °C and 0.37 cps/day @ -55 °C, with a significant suppression effect on radiation-induced dark counts at lower operating temperature. Based on the proposed radiation damage induced dark count annealing model, simulations were conducted for the in-orbit dark counts of the detector, the simulation results are consistent with in-orbit test data. In May 2022, four of these detectors underwent a cumulative 5.7 hours high-temperature annealing test at 76 °C, dark count rate shows no measurable changes, consistent with annealing model. As of now, these ten APD single-photon detectors on the Micius Quantum Science Experimental Satellite have been in operation for approximately 2507 days and are still functioning properly, providing valuable experience for the future long-term space applications of silicon APD single-photon detectors.

5.
Biomed Environ Sci ; 37(3): 242-253, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38582989

RESUMO

Objective: This study aimed to evaluate the associations of serum folate and/or vitamin B 12 concentrations with obesity among Chinese children and adolescents. Methods: A cross-sectional study was conducted including 3,079 Chinese children and adolescents, aged 6 to 17 years, from Jiangsu, China. Anthropometric indices, such as, children's body mass index (BMI), BMI z-scores, waist circumference, and waist-to-height ratio were utilized. Multivariable linear regression and generalized additive models were used to investigate the associations of serum folate and vitamin B 12 levels with anthropometric indices and odds of obesity. Results: We observed that serum vitamin B 12 concentrations were inversely associated with all anthropometric indices and the odds of general obesity [odds ratio ( OR) = 0.68; 95% confidence interval ( CI) = 0.59, 0.78] and abdominal obesity ( OR = 0.68; 95% CI = 0.60, 0.77). When compared to participants with both serum vitamin levels in the two middle quartiles, those with both serum folate and vitamin B 12 levels in the highest quartile were less prone to general ( OR = 0.31, 95% CI = 0.19, 0.50) or abdominal obesity ( OR = 0.46, 95% CI = 0.31, 0.67). Conversely, participants with vitamin B 12 levels in the lowest quartile alongside folate levels in the highest quartile had higher odds of abdominal obesity ( OR = 2.06, 95% CI = 1.09, 3.91). Conclusion: Higher serum vitamin B 12 concentrations, but not serum folate concentrations, were associated with lower odds of childhood obesity. Children and adolescents with high levels of vitamin B 12 and folate were less likely to be obese.


Assuntos
Obesidade Pediátrica , Vitamina B 12 , Humanos , Criança , Adolescente , Obesidade Abdominal , Estudos Transversais , Obesidade Pediátrica/epidemiologia , Fatores de Risco , Índice de Massa Corporal , Ácido Fólico , Vitaminas
6.
Heliyon ; 10(8): e28543, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38628704

RESUMO

Objective: Individual differences were observed in the clinical efficacy of Botulinum toxin A (BoNT-A) in the treatment of the primary Meige syndrome. Our study aimed to explore the potential associations between the clinical efficacy of BoNT-A in the treatment of the primary Meige syndrome and variants of SNAP25, SV2C and ST3GAL2, which are involving in the translocation of the BoNT-A in vivo. Methods: Patients with the primary Meige syndrome treated with BoNT-A were enrolled. Clinical efficacy was evaluated by the maximum improvement rate of motor symptoms and the duration of efficacy. Variants of SNAP25, SV2C and ST3GAL2 were obtained by Sanger sequencing. Another cohort diagnosed with primary cervical dystonia was also enrolled in the replication stage. Results: Among the 104 primary Meige syndrome patients, 80 patients (76.9%) had a good efficacy (the maximum improvement rate of motor symptoms ≥30%) and 24 (23. 1%) had a poor (the maximum improvement rate of motor symptoms <30%). As to the duration of efficacy, 52 patients (50.0%) had a long duration of efficacy (≥4 months), and 52 (50.0%) had a short (<4 months). In terms of primary Meige syndrome, SNAP25 rs6104571 was found associating with the maximum improvement rate of motor symptoms (Genotype: P = 0.02, OR = 0.26; Allele: P = 0.013, OR = 0.29), and SV2C rs31244 was found associating with the duration of efficacy (Genotype: P = 0.024, OR = 0.13; Allele: P = 0.012, OR = 0.13). Besides, we also conducted the association analyses between the variants and BoNT-A-related adverse reactions. Although, there was no statistical difference between the allele of SV2C rs31244 and BoNT-A-related adverse reactions, there was a trend (P = 0.077, OR = 2.56). In the replication stage, we included 39 patients with primary cervical dystonia to further expanding the samples' size. Among the 39 primary cervical dystonia patients, 25 patients (64.1%) had a good efficacy (the maximum improvement rate of motor symptoms ≥50%) and 14 (35.9%) had a poor (the maximum improvement rate of motor symptoms <50%). As to the duration of efficacy, 32 patients (82.1%) had a long duration of efficacy (≥6 months), and 7 (17.9%) had a short (<6 months). Integrating primary Meige syndrome and primary cervical dystonia, SV2C rs31244 was still found associating with the duration of efficacy (Genotype: P = 0.002, OR = 0. 23; Allele: P = 0.001, OR = 0. 25). Conclusion: In our study, SNAP25 rs6104571 was associated with the maximum improvement rate of motor symptoms in patients with primary Meige syndrome treated with BoNT-A, and patients carrying this variant had a lower improvement rate of motor symptoms. SV2C rs31244 was associated with duration of treatment in patients with primary Meige syndrome treated with BoNT-A and patients carrying this variant had a shorter duration of treatment. Patients with primary Meige syndrome carrying SV2C rs31244 G allele have an increase likelihood of BoNT-A-related adverse reactions. Involving 39 patients with primary cervical dystonia, the results further verify that SV2C rs31244 was associated with duration of treatment and patients carrying this variant had a shorter duration of treatment.

8.
World J Gastrointest Oncol ; 16(4): 1309-1318, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38660663

RESUMO

BACKGROUND: Despite continuous changes in treatment methods, the survival rate for advanced hepatocellular carcinoma (HCC) patients remains low, highlighting the importance of diagnostic methods for HCC. AIM: To explore the efficacy of texture analysis based on multi-parametric magnetic resonance (MR) imaging (MRI) in predicting microvascular invasion (MVI) in preoperative HCC. METHODS: This study included 105 patients with pathologically confirmed HCC, categorized into MVI-positive and MVI-negative groups. We employed Original Data Analysis, Principal Component Analysis, Linear Discriminant Analysis (LDA), and Non-LDA (NDA) for texture analysis using multi-parametric MR images to predict preoperative MVI. The effectiveness of texture analysis was determined using the B11 program of the MaZda4.6 software, with results expressed as the misjudgment rate (MCR). RESULTS: Texture analysis using multi-parametric MRI, particularly the MI + PA + F dimensionality reduction method combined with NDA discrimination, demonstrated the most effective prediction of MVI in HCC. Prediction accuracy in the pulse and equilibrium phases was 83.81%. MCRs for the combination of T2-weighted imaging (T2WI), arterial phase, portal venous phase, and equilibrium phase were 22.86%, 16.19%, 20.95%, and 20.95%, respectively. The area under the curve for predicting MVI positivity was 0.844, with a sensitivity of 77.19% and specificity of 91.67%. CONCLUSION: Texture analysis of arterial phase images demonstrated superior predictive efficacy for MVI in HCC compared to T2WI, portal venous, and equilibrium phases. This study provides an objective, non-invasive method for preoperative prediction of MVI, offering a theoretical foundation for the selection of clinical therapy.

9.
Trials ; 25(1): 200, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509589

RESUMO

BACKGROUND: The neural cells in the brains of patients with Parkinson's disease (PWP) display aberrant synchronized oscillatory activity within the beta frequency range. Additionally, enhanced gamma oscillations may serve as a compensatory mechanism for motor inhibition mediated by beta activity and also reinstate plasticity in the primary motor cortex affected by Parkinson's disease. Transcranial alternating current stimulation (tACS) can synchronize endogenous oscillations with exogenous rhythms, thereby modulating cortical activity. The objective of this study is to investigate whether the addition of tACS to multidisciplinary intensive rehabilitation treatment (MIRT) can improve symptoms of PWP so as to enhance the quality of life in individuals with Parkinson's disease based on the central-peripheral-central theory. METHODS: The present study was a randomized, double-blind trial that enrolled 60 individuals with Parkinson's disease aged between 45 and 70 years, who had Hoehn-Yahr scale scores ranging from 1 to 3. Participants were randomly assigned in a 1:1 ratio to either the tACS + MIRT group or the sham-tACS + MIRT group. The trial consisted of a two-week double-blind treatment period followed by a 24-week follow-up period, resulting in a total duration of twenty-six weeks. The primary outcome measured the change in PDQ-39 scores from baseline (T0) to 4 weeks (T2), 12 weeks (T3), and 24 weeks (T4) after completion of the intervention. The secondary outcome assessed changes in MDS-UPDRS III scores at T0, the end of intervention (T1), T2, T3, and T4. Additional clinical assessments and mechanistic studies were conducted as tertiary outcomes. DISCUSSION: The objective of this study is to demonstrate that tACS can enhance overall functionality and improve quality of life in PWP, based on the framework of MIRT. Additionally, it seeks to establish a potential correlation between these therapeutic effects and neuroplasticity alterations in relevant brain regions. The efficacy of tACS will be assessed during the follow-up period in order to optimize neuroplasticity and enhance its potential impact on rehabilitation efficiency for PWP. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2300071969. Registered on 30 May 2023.


Assuntos
Doença de Parkinson , Estimulação Transcraniana por Corrente Contínua , Humanos , Pessoa de Meia-Idade , Idoso , Doença de Parkinson/diagnóstico , Doença de Parkinson/terapia , Doença de Parkinson/complicações , Estimulação Transcraniana por Corrente Contínua/efeitos adversos , Estimulação Transcraniana por Corrente Contínua/métodos , Qualidade de Vida , Terapia por Exercício/métodos , Método Duplo-Cego , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
J Agric Food Chem ; 72(12): 6372-6388, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38471112

RESUMO

Oxidative damage to the kidneys is a primary factor in the occurrence of kidney stones. This study explores the inhibitory effect of Porphyra yezoensis polysaccharides (PYP) on oxalate-induced renal injury by detecting levels of oxidative damage, expression of adhesion molecules, and damage to intracellular organelles and revealed the molecular mechanism by molecular biology methods. Additionally, we validated the role of PYP in vivo using a crystallization model of hyperoxalate-induced rats. PYP effectively scavenged the overproduction of reactive oxygen species (ROS) in HK-2 cells, inhibited the adhesion of calcium oxalate (CaOx) crystals on the cell surface, unblocked the cell cycle, restored the depolarization of the mitochondrial membrane potential, and inhibited cell death. PYP upregulated the expression of antioxidant proteins, including Nrf2, HO-1, SOD, and CAT, while decreasing the expression of Keap-1, thereby activating the Keap1/Nrf2 signaling pathway. PYP inhibited CaOx deposition in renal tubules in the rat crystallization model, significantly reduced high oxalate-induced renal injury, decreased the levels of the cell surface adhesion proteins, improved renal function in rats, and ultimately inhibited the formation of kidney stones. Therefore, PYP, which has crystallization inhibition and antioxidant properties, may be a therapeutic option for the treatment of kidney stones.


Assuntos
Oxalato de Cálcio , 60578 , Cálculos Renais , Porphyra , Ratos , Animais , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Oxalato de Cálcio/metabolismo , Oxalato de Cálcio/farmacologia , Antioxidantes/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Rim/metabolismo , Cálculos Renais/metabolismo , Estresse Oxidativo , Oxalatos/metabolismo , Oxalatos/farmacologia , Polissacarídeos/metabolismo
11.
FEBS Open Bio ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38538106

RESUMO

The extracellular matrix (ECM) regulates carcinogenesis by interacting with cancer cells via cell surface receptors. Discoidin Domain Receptor 2 (DDR2) is a collagen-activated receptor implicated in cell survival, growth, and differentiation. Dysregulated DDR2 expression has been identified in various cancer types, making it as a promising therapeutic target. Additionally, cancer cells exhibit mechanosensing abilities, detecting changes in ECM stiffness, which is particularly important for carcinogenesis given the observed ECM stiffening in numerous cancer types. Despite these, whether collagen-activated DDR2 signaling and ECM stiffness-induced mechanosensing exert similar effects on cancer cell behavior and whether they operate through analogous mechanisms remain elusive. To address these questions, we performed bulk RNA sequencing (RNA-seq) on human SH-SY5Y neuroblastoma cells cultured on collagen-coated substrates. Our results show that DDR2 downregulation induces significant changes in the cell transcriptome, with changes in expression of 15% of the genome, specifically affecting the genes associated with cell division and differentiation. We validated the RNA-seq results by showing that DDR2 knockdown redirects the cell fate from proliferation to senescence. Like DDR2 knockdown, increasing substrate stiffness diminishes cell proliferation. Surprisingly, RNA-seq indicates that substrate stiffness has no detectable effect on the transcriptome. Furthermore, DDR2 knockdown influences cellular responses to substrate stiffness changes, highlighting a crosstalk between these two ECM-induced signaling pathways. Based on our results, we propose that the ECM could activate DDR2 signaling and mechanosensing in cancer cells to orchestrate their cell fate through distinct mechanisms, with or without involving gene expression, thus providing novel mechanistic insights into cancer progression.

12.
Science ; 383(6689): 1302-1303, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38513007
13.
iScience ; 27(4): 109358, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38544565

RESUMO

Mesenchymal stem cell (MSC)-mediated coupling of osteogenesis and angiogenesis is a critical phenomenon in bone formation. Herein, we investigated the role and mechanism of SGMS1 in the osteogenic differentiation of MSCs and, in combination with osteogenesis and angiogenesis, to discover new therapeutic targets for skeletal dysplasia and bone defects. SGMS1 addition accelerated MSC osteogenic differentiation, whereas SGMS1 silencing suppressed this process. Moreover, SGMS1 overexpression inhibited ceramide (Cer) and promoted sphingomyelin (SM) levels. SM treatment neutralized the suppressive effect of shSGMS1 on osteogenesis. SGMS1 restrained PP2A activity by regulating Cer/SM metabolism and thus enhanced the levels of phosphorylated Akt, Runx2, and vascular endothelial growth factor (VEGF). Furthermore, SGMS1 transcription was regulated by Runx2. SGMS1 increased MSC-mediated angiogenesis by promoting VEGF expression. SGMS1 addition promoted rat bone regeneration in vivo. In conclusion, SGMS1 induces osteogenic differentiation of MSCs and osteogenic-angiogenic coupling through the regulation of the Cer/PP2A/Akt signaling pathway.

14.
Chem Sci ; 15(11): 4106-4113, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38487231

RESUMO

The modulation of two-dimensional metal-organic framework (2-D MOF) nanosheet stacking is an effective means to improve the properties and promote the application of nanosheets in various fields. Here, we employed a series of alcohol guest molecules (MeOH, EtOH and PrOH) to modulate Zr-BTB (BTB = benzene-1,3,5-tribenzoate) nanosheets and to generate untwisted stacking. The distribution of stacking angles was statistically analyzed from high-angle annular dark-field (HAADF) and fast Fourier transform (FFT) images. The ratios of untwisted stacking were calculated, such as 77.01% untwisted stacking for MeOH, 83.45% for EtOH, and 85.61% for PrOH. The obtained untwisted Zr-BTB showed good separation abilities for different substituted benzene isomers, superior para selectivity and excellent column stability and reusability. Control experiments of 2-D Zr-TCA (TCA = 4,4',4''-tricarboxytriphenylamine) and Zr-TATB (TATB = 4,4',4''-(1,3,5-triazine-2,4,6-triyl)tribenzoic acid) nanosheets with similar pore sizes and stronger polarity regulated by the alcohol guests exhibited moderate separation performance. The electron microscopy images revealed that polar alcohol regulation dominantly generated the twisted stacking of Zr-TCA and Zr-TATB with various Moiré patterns. Polar guest molecules, such as alcohols, provide strong host-guest interactions during the regulation of MOF nanosheet stacking, providing an opportunity to design new porous Moiré materials with application prospects.

15.
Mol Genet Genomic Med ; 12(3): e2401, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38444278

RESUMO

BACKGROUND: The MYH3-associated myosinopathies comprise a spectrum of rare neuromuscular disorders mainly characterized by distal arthrogryposis with or without other features like pterygia and vertebrae fusion. CPSKF1B (contractures, pterygia, and spondylocarpotarsal fusion syndrome1B) is the only known autosomal recessiveMYH3-associated myosinopathy so far, with no more than two dozen cases being reported. MATERIALS AND METHODS: A boy with CPSKF1B was recruited and subjected to a comprehensive clinical and imaging evaluation. Genetic detection with whole-exome sequencing (WES) was performed on the patient and extended family members to identify the causative variation. A series of in silico and in vitro investigations were carried out to verify the pathogenicity of the two variants of the identified compound heterozygous variation. RESULTS: The patient exhibited moderate CPSKF1B symptoms including multiarticular contractures, webbed neck, and spondylocarpotarsal fusion. WES detected a compound heterozygous MYH3 variation consisting of two variants, namely NM_002470.4: c.3377A>G; p. (E1126G) and NM_002470.4: c.5161-2A>C. It was indicated that the NM_002470.4: c.3377A>G; p. (E1126G) variant mainly impaired the local hydrogen bond formation and impacted the TGF-B pathway, while the NM_002470.4: c.5161-2A>C variant could affect the normal splicing of pre-mRNA, resulting in the appearance of multiple abnormal transcripts. CONCLUSIONS: The findings of this study expanded the mutation spectrum of CPSKF1B, provided an important basis for the counseling of the affected family, and also laid a foundation for the functional study of MYH3 mutations.


Assuntos
Artrogripose , Túnica Conjuntiva , Contratura , Pterígio , Humanos , Masculino , Artrogripose/genética , Túnica Conjuntiva/anormalidades , Contratura/genética , Família
16.
Ying Yong Sheng Tai Xue Bao ; 35(2): 480-488, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38523106

RESUMO

The construction of urban ecological green wedges, which can mitigate the heat island effect through cooling and ventilation effects, is an important way to enhance the adaptation of cities to climate change. Dynamic monitoring and periodic assessment of both the conservation status and cooling effect of ecological green wedges is a key to ensure the heat mitigation benefits. Based on multi-source remote sensing data, we systematically analyzed the land use changes of six ecological green wedges in Wuhan in 2013 and 2020 using the methods of Markov transfer matrix, land use dynamics, and comprehensive index of land use degree, and evaluated the changes in surface temperature of the ecological green wedges and their cooling island effect. Results showed that the ecological green wedges in Wuhan generally had a large amount of construction land encroaching on ecological land from 2013 to 2020, with the water decreased the most. With the continuous deterioration of ecological green wedges, their land surface temperatures showed rising trends, together with significant weakening trends in cooling island effects. Among all the six wedges, the Dadonghu, Tangxun, and Wuhu exhibited relatively better ecological conservation, slighter land use change and lower overall development degree. Qinglinghu and Houguanhu demonstrated average levels of conservation. Fuhe experienced the most severe change under the significant influence of the westward policy of Wuhan City, with the proportion of water decreasing by 7.1%, warming up by 3.00 ℃, and the largest reduction in cooling distance for the cooling island effect, amounting to about 210 m. The results provided scientific evidence for the urban heat island mitigation-oriented planning and management of ecological green wedges for Wuhan City.


Assuntos
Temperatura Alta , Água , Cidades , Temperatura , China , Monitoramento Ambiental/métodos
17.
ACS Cent Sci ; 10(2): 358-366, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38435533

RESUMO

Encapsulating enzymes within metal-organic frameworks has enhanced their structural stability and interface tunability for catalysis. However, the small apertures of the frameworks restrict their effectiveness to small organic molecules. Herein, we present a green strategy directed by visible linker micelles for the aqueous synthesis of MAF-6 that enables enzymes for the catalytic asymmetric synthesis of chiral molecules. Due to the large pore aperture (7.6 Å), double the aperture size of benchmark ZIF-8 (3.4 Å), MAF-6 allows encapsulated enzyme BCL to access larger substrates and do so faster. Through the optimization of surfactants' effect during synthesis, BCL@MAF-6-SDS (SDS = sodium dodecyl sulfate) displayed a catalytic efficiency (Kcat/Km) that was 420 times greater than that of BCL@ZIF-8. This biocomposite efficiently catalyzed the synthesis of drug precursor molecules with 94-99% enantioselectivity and nearly quantitative yields. These findings represent a deeper understanding of de novo synthetic encapsulation of enzyme in MOFs, thereby unfolding the great potential of enzyme@MAF catalysts for asymmetric synthesis of organics and pharmaceuticals.

18.
Appl Opt ; 63(4): 982-989, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38437395

RESUMO

In underwater wireless optical communication (UWOC), vortex beams carrying orbital angular momentum (OAM) can improve channel capacity but are vulnerable to oceanic turbulence (OT), leading to recognition errors. To mitigate this issue, we propose what we believe to be a novel method that combines the Gerchberg-Saxton (GS) algorithm-based recovery with convolutional neural network (CNN)-based recognition (GS-CNN). Our experimental results demonstrate that superposed Laguerre-Gaussian (LG) beams with small topological charge are ideal information carriers, and the GS-CNN remains effective even when OT strength C n2 is high up to 10-11 K 2 m -2/3. Furthermore, we use 16 kinds of LG beams to transmit a 256-grayscale digital image, giving rise to an increase in recognition accuracy from 0.75 to 0.93 and a decrease in bit error ratio from 3.98×10-2 to 6.52×10-3 compared to using the CNN alone.

19.
Huan Jing Ke Xue ; 45(3): 1665-1673, 2024 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471878

RESUMO

Changes in soil nitrogen components in tea gardens affect the soil nitrogen supply capacity and nitrogen cycle. In this study, soil samples were collected from forest land, cultivated land, and tea gardens with different plantation ages (30, 50, and 70 years) to explore the changes in soil nitrogen components and their relationship with physicochemical properties and enzyme activities. The results showed that:① with the increase in tea plantation age, the silt, total phosphorus, and urease and catalase activities gradually increased, whereas the sand, clay, pH, electrical conductivity, soil organic carbon, and the activities of invertase gradually decreased. The alkaline phosphatase activity increased first and then decreased with the increase in tea plantation age, and no significant differences were observed in soil water content and acid phosphatase activity. ② With the increase in tea plantation age, the contents of acid ammonia nitrogen, amino acid nitrogen, and nitrate nitrogen (NO3--N) increased significantly, and the contents of total nitrogen, acid ammonia nitrogen, hydrolyzable unknown nitrogen, and non-hydrolyzable nitrogen in tea gardens were significantly higher than those in forest land. ③ The total phosphorus, alkaline phosphatase, and urease were the main factors affecting soil nitrogen components. Among them, organic nitrogen components were significantly correlated with total phosphorus and alkaline phosphatase, and inorganic nitrogen components were significantly correlated with alkaline phosphatase, whereas total nitrogen had significant correlations with sand, silt, total phosphorus, urease, and alkaline phosphatase.


Assuntos
Fosfatase Alcalina , Solo , Solo/química , Areia , Nitrogênio/análise , Carbono , Urease , Amônia , Fósforo/análise , Chá , Microbiologia do Solo , China
20.
JAMA Netw Open ; 7(3): e241651, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38457184

RESUMO

This cross-sectional study examines COVID-19 pandemic­related changes in rates of neonatal abstinence syndrome (NAS) and whether infants in urban or rural areas and those with low socioeconomic status were disproportionately affected.


Assuntos
COVID-19 , Síndrome de Abstinência Neonatal , Transtornos Relacionados ao Uso de Opioides , Recém-Nascido , Humanos , Síndrome de Abstinência Neonatal/epidemiologia , Síndrome de Abstinência Neonatal/tratamento farmacológico , Pandemias , Analgésicos Opioides/uso terapêutico , Transtornos Relacionados ao Uso de Opioides/epidemiologia
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