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1.
Appl Opt ; 63(8): 2056-2064, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38568647

RESUMO

The optical distortion of the lithographic projection lens can reduce imaging quality and cause overlay errors in lithography, thus preventing the miniaturization of printed patterns. In this paper, we propose a technique to measure the optical distortion of a lithographic projection lens by sensing the wavefront aberrations of the lens. A multichannel dual-grating lateral shearing interferometer is used to measure the wavefront aberrations at several field points in the pupil plane simultaneously. Then, the distortion at these field points is derived according to the proportional relationship between the Z 2 and Z 3 Zernike terms (the tilt terms) and the image position shifts. Without the need for additional devices, our approach can simultaneously retrieve both the wavefront aberrations and the image distortion information. Consequently, it improves not only measurement speed and accuracy but also enables accounting for displacement stage positioning error. Experiments were conducted on a lithographic projection lens with a numerical aperture of 0.57 to verify the feasibility of the proposed method.

2.
Front Microbiol ; 15: 1364425, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38450166

RESUMO

Engineering Saccharomyces cerevisiae for biodegradation and transformation of industrial toxic substances such as catechol (CA) has received widespread attention, but the low tolerance of S. cerevisiae to CA has limited its development. The exploration and modification of genes or pathways related to CA tolerance in S. cerevisiae is an effective way to further improve the utilization efficiency of CA. This study identified 36 genes associated with CA tolerance in S. cerevisiae through genome-wide identification and bioinformatics analysis and the ERG6 knockout strain (ERG6Δ) is the most sensitive to CA. Based on the omics analysis of ERG6Δ under CA stress, it was found that ERG6 knockout affects pathways such as intrinsic component of membrane and pentose phosphate pathway. In addition, the study revealed that 29 genes related to the cell wall-membrane system were up-regulated by more than twice, NADPH and NADP+ were increased by 2.48 and 4.41 times respectively, and spermidine and spermine were increased by 2.85 and 2.14 times, respectively, in ERG6Δ. Overall, the response of cell wall-membrane system, the accumulation of spermidine and NADPH, as well as the increased levels of metabolites in pentose phosphate pathway are important findings in improving the CA resistance. This study provides a theoretical basis for improving the tolerance of strains to CA and reducing the damage caused by CA to the ecological environment and human health.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38442048

RESUMO

Grading laryngeal squamous cell carcinoma (LSCC) based on histopathological images is a clinically significant yet challenging task. However, more low-effect background semantic information appeared in the feature maps, feature channels, and class activation maps, which caused a serious impact on the accuracy and interpretability of LSCC grading. While the traditional transformer block makes extensive use of parameter attention, the model overlearns the low-effect background semantic information, resulting in ineffectively reducing the proportion of background semantics. Therefore, we propose an end-to-end network with transformers constrained by learned-parameter-free attention (LA-ViT), which improve the ability to learn high-effect target semantic information and reduce the proportion of background semantics. Firstly, according to generalized linear model and probabilistic, we demonstrate that learned-parameter-free attention (LA) has a stronger ability to learn highly effective target semantic information than parameter attention. Secondly, the first-type LA transformer block of LA-ViT utilizes the feature map position subspace to realize the query. Then, it uses the feature channel subspace to realize the key, and adopts the average convergence to obtain a value. And those construct the LA mechanism. Thus, it reduces the proportion of background semantics in the feature maps and feature channels. Thirdly, the second-type LA transformer block of LA-ViT uses the model probability matrix information and decision level weight information to realize key and query, respectively. And those realize the LA mechanism. So, it reduces the proportion of background semantics in class activation maps. Finally, we build a new complex semantic LSCC pathology image dataset to address the problem, which is less research on LSCC grading models because of lacking clinically meaningful datasets. After extensive experiments, the whole metrics of LA-ViT outperform those of other state-of-the-art methods, and the visualization maps match better with the regions of interest in the pathologists' decision-making. Moreover, the experimental results conducted on a public LSCC pathology image dataset show that LA-ViT has superior generalization performance to that of other state-of-the-art methods.

4.
Nurse Educ Pract ; 76: 103896, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38377933

RESUMO

AIM: To explore the application effect of competency-based education (CBE) combined with multi-disciplinary team (MDT) teaching mode in respiratory rehabilitation nursing teaching. BACKGROUND: Respiratory rehabilitation, as an important non drug treatment for chronic respiratory disease, started late in China, with low implementation rate in hospitals and insufficient knowledge of nursing staff. Therefore, it is urgent to cultivate high professional level nurses with strong professional ability. DESIGN: A randomized controlled trial. METHODS: We selected nurses from the respiratory and critical care department at a Grade III, Level A hospital in Beijing, who participated in the respiratory rehabilitation training program between March 2020 and August 2022, as our study participants. Participants were grouped using a random number method. Nurses who participated in the study from March 2020 to May 2021 were set as the control group, and the nurses who participated in the study from June 2021 to August 2022 were set as the test group. The control group used traditional teaching methods, and the test group used the CBE combined MDT teaching model. At the end of the test, the theory, operating skills, satisfaction and core competence were assessed. RESULTS: After training, the theoretical examination score of the test group (93.71 ± 1.94) was higher than that of the control group (92.37 ± 1.92), the operational examination score of the test group (93.11 ± 2.12) was higher than that of the control group (91.61 ± 1.93), the overall teaching satisfaction of the test group (4.45 ± 0.50) was higher than that of the control group (4.13 ± 0.57), and the total score of the core competence of the test group (148.73 ± 7.08) was higher than that of the control group (141.02 ± 6.41). The difference between the two groups was statistically significant (P<0.05). CONCLUSION: CBE combined with MDT teaching mode has a good effect in Pulmonary and Critical Care Medicine (PCCM) respiratory rehabilitation nursing teaching.


Assuntos
Educação Baseada em Competências , Enfermagem em Reabilitação , Humanos , China , Competência Clínica
5.
Epilepsia ; 65(1): 46-56, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37347512

RESUMO

OBJECTIVES: Although hemispheric surgeries are among the most effective procedures for drug-resistant epilepsy (DRE) in the pediatric population, there is a large variability in seizure outcomes at the group level. A recently developed HOPS score provides individualized estimation of likelihood of seizure freedom to complement clinical judgement. The objective of this study was to develop a freely accessible online calculator that accurately predicts the probability of seizure freedom for any patient at 1-, 2-, and 5-years post-hemispherectomy. METHODS: Retrospective data of all pediatric patients with DRE and seizure outcome data from the original Hemispherectomy Outcome Prediction Scale (HOPS) study were included. The primary outcome of interest was time-to-seizure recurrence. A multivariate Cox proportional-hazards regression model was developed to predict the likelihood of post-hemispheric surgery seizure freedom at three time points (1-, 2- and 5- years) based on a combination of variables identified by clinical judgment and inferential statistics predictive of the primary outcome. The final model from this study was encoded in a publicly accessible online calculator on the International Network for Epilepsy Surgery and Treatment (iNEST) website (https://hops-calculator.com/). RESULTS: The selected variables for inclusion in the final model included the five original HOPS variables (age at seizure onset, etiologic substrate, seizure semiology, prior non-hemispheric resective surgery, and contralateral fluorodeoxyglucose-positron emission tomography [FDG-PET] hypometabolism) and three additional variables (age at surgery, history of infantile spasms, and magnetic resonance imaging [MRI] lesion). Predictors of shorter time-to-seizure recurrence included younger age at seizure onset, prior resective surgery, generalized seizure semiology, FDG-PET hypometabolism contralateral to the side of surgery, contralateral MRI lesion, non-lesional MRI, non-stroke etiologies, and a history of infantile spasms. The area under the curve (AUC) of the final model was 73.0%. SIGNIFICANCE: Online calculators are useful, cost-free tools that can assist physicians in risk estimation and inform joint decision-making processes with patients and families, potentially leading to greater satisfaction. Although the HOPS data was validated in the original analysis, the authors encourage external validation of this new calculator.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia , Hemisferectomia , Espasmos Infantis , Criança , Humanos , Hemisferectomia/métodos , Espasmos Infantis/cirurgia , Estudos Retrospectivos , Fluordesoxiglucose F18 , Resultado do Tratamento , Epilepsia/diagnóstico por imagem , Epilepsia/cirurgia , Convulsões/diagnóstico , Convulsões/etiologia , Convulsões/cirurgia , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/cirurgia , Imageamento por Ressonância Magnética , Eletroencefalografia
6.
ACS Nano ; 18(1): 272-280, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38096138

RESUMO

Two-dimensional (2D) semiconductors, such as transition metal dichalcogenides, have emerged as important candidate materials for next-generation chip-scale optoelectronic devices with the development of large-scale production techniques, such as chemical vapor deposition (CVD). However, 2D materials need to be transferred to other target substrates after growth, during which various micro- and nanoscale defects, such as nanobubbles, are inevitably generated. These nanodefects not only influence the uniformity of 2D semiconductors but also may significantly alter the local optoelectronic properties of the composed devices. Hence, super-resolution discrimination and characterization of nanodefects are highly demanded. Here, we report a near-field nanophotoluminescence (nano-PL) microscope that can quickly screen nanobubbles and investigate their impact on local excitonic properties of 2D semiconductors by directly visualize the PL emission distribution with a very high spatial resolution of ∼10 nm, far below the optical diffraction limit, and a high speed of 10 ms/point under ambient conditions. By using nano-PL microscopy to map the exciton and trion emission intensity distributions in transferred CVD-grown monolayer tungsten disulfide (1L-WS2) flakes, it is found that the PL intensity decreases by 13.4% as the height of the nanobubble increases by every nanometer, which is mainly caused by the suppression of trion emission due to the strong doping effect from the substrate. In addition to the nanobubbles, other types of nanodefects, such as cracks, stacks, and grain boundaries, can also be characterized. The nano-PL method is proven to be a powerful tool for the nondestructive quality inspection of nanodefects as well as the super-resolution exploration of local optoelectronic properties of 2D materials.

7.
BMC Microbiol ; 23(1): 382, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38049732

RESUMO

In bioethanol production, the main by-product, 5-hydroxymethylfurfural (HMF), significantly hinders microbial fermentation. Therefore, it is crucial to explore genes related to HMF tolerance in Saccharomyces cerevisiae for enhancing the tolerance of ethanol fermentation strains. A comprehensive analysis was conducted using genome-wide deletion library scanning and SGAtools, resulting in the identification of 294 genes associated with HMF tolerance in S. cerevisiae. Further KEGG and GO enrichment analysis revealed the involvement of genes OCA1 and SIW14 in the protein phosphorylation pathway, underscoring their role in HMF tolerance. Spot test validation and subcellular structure observation demonstrated that, following a 3-h treatment with 60 mM HMF, the SIW14 gene knockout strain exhibited a 12.68% increase in cells with abnormal endoplasmic reticulum (ER) and a 22.41% increase in the accumulation of reactive oxygen species compared to the BY4741 strain. These findings indicate that the SIW14 gene contributes to the protection of the ER structure within the cell and facilitates the clearance of reactive oxygen species, thereby confirming its significance as a key gene for HMF tolerance in S. cerevisiae.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Técnicas de Inativação de Genes , Fermentação
8.
iScience ; 26(12): 108484, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38094246

RESUMO

Fibrosis disrupts tissue balance and links to severe illnesses, impairing organ function and, in some cases, even fatality. The interaction between M2 macrophages and fibroblasts is vital for tissue equilibrium. Transforming growth factor ß1 (TGF-ß1) released by M2 macrophages plays a central role in fibrosis, regulating fibroblast activity and extracellular matrix metabolism. Targeting TGF-ß1 is key to fibrosis treatment. In our study using three fibroblast cell lines, we reveal that the M2 macrophage transcription factor SP1 enhances binding to the TGF-ß1 promoter motif, promoting TGF-ß1 transcription and activating fibroblasts (This process does not involve changes in DNA methylation levels surrounding the motif sequence). The zinc fingers in SP1's DNA-binding domain 3 are crucial for this binding. In vivo, targeting SP1 in rat ligaments significantly reduces extracellular matrix accumulation. Our findings highlight SP1 as a promising target for regulating tissue extracellular matrix and combating fibrosis.

9.
Microsc Microanal ; 29(6): 1879-1888, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37947075

RESUMO

Extended defects, like threading dislocations, are detrimental to the performance of optoelectronic devices. In the scanning electron microscope, dislocations are traditionally imaged using diodes to monitor changes in backscattered electron intensity as the electron beam is scanned over the sample, with the sample positioned so the electron beam is at, or close to the Bragg angle for a crystal plane/planes. Here, we use a pixelated detector instead of single diodes, specifically an electron backscatter diffraction (EBSD) detector. We present postprocessing techniques to extract images of dislocations and surface steps, for a nitride thin film, from measurements of backscattered electron intensities and intensity distributions in unprocessed EBSD patterns. In virtual diode (VD) imaging, the backscattered electron intensity is monitored for a selected segment of the unprocessed EBSD patterns. In center of mass (COM) imaging, the position of the center of the backscattered electron intensity distribution is monitored. Additionally, both methods can be combined (VDCOM). Using both VD and VDCOM, images of only threading dislocations, or dislocations and surface steps can be produced, with VDCOM images exhibiting better signal-to-noise. The applicability of VDCOM imaging is demonstrated across a range of nitride semiconductor thin films, with varying surface step and dislocation densities.

10.
Toxins (Basel) ; 15(8)2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37624232

RESUMO

Aflatoxins are potent carcinogenic compounds, mainly produced by fungi species of the genus Aspergillus in the soil. Because of their stability, they are difficult to remove completely, even under extreme conditions. Aflatoxin contamination is one of the main causes of safety in peanuts, maize, wheat and other agricultural products. Aflatoxin contamination originates from the soil. Through the investigation of soil properties and soil microbial distribution, the sources of aflatoxin are identified, aflatoxin contamination is classified and analysed, and post-harvest crop detoxification and corresponding contamination prevention measures are identified. This includes the team's recent development of the biofungicide ARC-BBBE (Aflatoxin Rhizobia Couple-B. amyloliquefaciens, B. laterosporu, B. mucilaginosus, E. ludwiggi) for field application and nanomaterials for post-production detoxification of cereals and oilseed crops, providing an effective and feasible approach for the prevention and control of aflatoxin contamination. Finally, it is hoped that effective preventive and control measures can be applied to a large number of cereal and oilseed crops.


Assuntos
Aflatoxinas , Solo , Aflatoxina B1 , Agricultura , Arachis , Produtos Agrícolas , Grão Comestível
11.
Angew Chem Int Ed Engl ; 62(34): e202305693, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37392153

RESUMO

Anisotropy is an intrinsic property of crystalline materials. However, the photoluminescence anisotropy in eutectic crystals of organometallic complexes has remained unexplored. Herein, the eutectic of polynuclear lanthanide complexes and Ag clusters was prepared, and the crystal shows significant photoluminescence anisotropy. The polarization anisotropy of emission δ and degree of excitation polarization P are 2.62 and 0.53, respectively. The rare excitation polarization properties have been proved to be related to the regular arrangement of electric transition dipole moments of luminescent molecules in the crystal. Our design provides a reference for developing new photoluminescence anisotropy materials and expanding their applications.

12.
Phytomedicine ; 117: 154907, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37295024

RESUMO

BACKGROUND: The diterpenoid alkaloids belong to a highly esteemed group of natural compounds, which display significant biological activities. It is a productive strategy to expand the chemical space of these intriguing natural compounds for drug discovery. METHODS: We prepared a series of new derivatives bearing diverse skeletons and functionalities from the diterpenoid alkaloids deltaline and talatisamine based on a diversity-oriented synthesis strategy. The anti-inflammatory activity of these derivatives was initially screened and evaluated by the release of nitric oxide (NO), tumor necrosis factor (TNF-α), and interleukin-6 (IL-6) in lipopolysaccharide (LPS)-activated RAW264.7 cells. Futhermore, the anti-inflammatory activity of the representative derivative 31a was validated in various inflammatory animal models, including phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mice ear edema, LPS-stimulated acute kidney injury, and collagen-induced arthritis (CIA). RESULTS: It was found that several derivatives were able to suppress the secretion of NO, TNF-α, and IL-6 in LPS-activated RAW264.7 cells. Compound 31a, one of the representative derivatives named as deltanaline, demonstrated the strongest anti-inflammatory effects in LPS-activated macrophages and three different animal models of inflammatory diseases by inhibiting nuclear factor kappa-B (NF-κB)/mitogen-activated protein kinase (MAPK) signaling and inducing autophagy. CONCLUSION: Deltanaline is a new structural compound derived from natural diterpenoid alkaloids, which may serve as a new lead compound for the treatment of inflammatory diseases.


Assuntos
Alcaloides , Diterpenos , Camundongos , Animais , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Anti-Inflamatórios/uso terapêutico , NF-kappa B/metabolismo , Alcaloides/farmacologia , Células RAW 264.7 , Diterpenos/farmacologia , Óxido Nítrico/metabolismo
13.
Front Immunol ; 14: 1155746, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37122738

RESUMO

Intervertebral disc degeneration (IDD) is a primary contributor to low back pain. Immune cells play an extremely important role in modulating the progression of IDD by interacting with disc nucleus pulposus (NP) cells and extracellular matrix (ECM). Encased within the annulus fibrosus, healthy NP is an avascular and immune-privileged tissue that does not normally interact with macrophages. However, under pathological conditions in which neovascularization is established in the damaged disc, NP establishes extensive crosstalk with macrophages, leading to different outcomes depending on the different microenvironmental stimuli. M1 macrophages are a class of immune cells that are predominantly pro-inflammatory and promote inflammation and ECM degradation in the NP, creating a vicious cycle of matrix catabolism that drives IDD. In contrast, NP cells interacting with M2 macrophages promote disc tissue ECM remodeling and repair as M2 macrophages are primarily involved in anti-inflammatory cellular responses. Hence, depending on the crosstalk between NP and the type of immune cells (M1 vs. M2), the overall effects on IDD could be detrimental or regenerative. Drug or surgical treatment of IDD can modulate this crosstalk and hence the different treatment outcomes. This review comprehensively summarizes the interaction between macrophages and NP, aiming to highlight the important role of immunology in disc degeneration.


Assuntos
Degeneração do Disco Intervertebral , Núcleo Pulposo , Humanos , Núcleo Pulposo/metabolismo , Degeneração do Disco Intervertebral/patologia , Macrófagos/metabolismo , Matriz Extracelular/metabolismo , Inflamação/metabolismo
14.
Front Pharmacol ; 14: 1118017, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37124193

RESUMO

Aberrant mitophagy has been identified as a driver for energy metabolism disorder in most cardiac pathological processes. However, finding effective targeted agents and uncovering their precise modulatory mechanisms remain unconquered. Fuzi, the lateral roots of Aconitum carmichaelii, shows unique efficacy in reviving Yang for resuscitation, which has been widely used in clinics. As a main cardiotonic component of Fuzi, mesaconine has been proven effective in various cardiomyopathy models. Here, we aimed to define a previously unrevealed cardioprotective mechanism of mesaconine-mediated restoration of obstructive mitophagy. The functional implications of mesaconine were evaluated in doxorubicin (DOX)-induced heart failure models. DOX-treated mice showed characteristic cardiac dysfunction, ectopic myocardial energy disorder, and impaired mitophagy in cardiomyocytes, which could be remarkably reversed by mesaconine. The cardioprotective effect of mesaconine was primarily attributed to its ability to promote the restoration of mitophagy in cardiomyocytes, as evidenced by elevated expression of PINK1, a key mediator of mitophagy induction. Silencing PINK1 or deactivating mitophagy could completely abolish the protective effects of mesaconine. Together, our findings suggest that the cardioprotective effects of mesaconine appear to be dependent on the activation of PINK1-induced mitophagy and that mesaconine may constitute a promising therapeutic agent for the treatment of heart failure.

15.
J Cancer Res Clin Oncol ; 149(11): 8581-8592, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37097394

RESUMO

PURPOSE: The classification of primary lung adenocarcinoma is complex and varied. Different subtypes of lung adenocarcinoma have different treatment methods and different prognosis. In this study, we collected 11 datasets comprising subtypes of lung cancer and proposed FL-STNet model to provide the assistance for improving clinical problems of pathologic classification in primary adenocarcinoma of lung. METHODS: Samples were collected from 360 patients diagnosed with lung adenocarcinoma and other subtypes of lung diseases. In addition, an auxiliary diagnosis algorithm based on Swin-Transformer, which used Focal Loss for function in training, was developed. Meanwhile, the diagnostic accuracy of the Swin-Transformer was compared to pathologists. RESULTS: The Swin-Transformer captures not only information in the overall tissue structure but also the local tissue details in the images of lung cancer pathology. Furthermore, training FL-STNet with the Focal Loss function can further balance the difference in the amount of data between different subtypes, improving recognition accuracy. The average classification accuracy, F1, and AUC of the proposed FL-STNet reached 85.71%, 86.57%, and 0.9903. The average accuracy of the FL-STNet was higher by 17% and 34%, respectively, than in the senior pathologist and junior pathologist group. CONCLUSION: The first deep learning based on an 11-category classifier was developed for classifying lung adenocarcinoma subtypes based on WSI histopathology. Aiming at the deficiencies of the current CNN and Vit, FL-STNet model is proposed in this study by introducing Focal Loss and combining the advantages of Swin-Transformer model.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Patologistas
16.
Sci Bull (Beijing) ; 68(7): 730-739, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36964088

RESUMO

With the rapid development of human lunar exploration projects, the lunar base establishment and resource utilization are on the way, and hence it is urgent and significant to reasonably predict engineering properties of the lunar regolith, which remains to be unclear due to limited lunar samples currently accessible for geotechnical tests. In this contribution, we aim to address this outstanding challenge from the perspective of granular material mechanics. To this end, the 3D multi-aspect geometrical characteristics and mechanical properties of Chang'e-5 lunar samples are for the first time evaluated with a series of non-destructive microscopic tests. Based on the measured particle surface roughness and Young's modulus, the interparticle friction coefficients of lunar regolith particles are well predicted through an experimental fitting approach using previously published data on terrestrial geomaterials or engineering materials. Then the residual friction angle of the lunar regolith under low confining pressure is predicted as 53° to 56° according to the particle overall regularity and interparticle friction coefficients of Chang'e-5 lunar samples. The presented results provide a novel cross-scale method to predict engineering properties of the lunar regolith from particle scale information to serve for the future lunar surface engineering construction.

17.
Opt Express ; 31(3): 4129-4139, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36785388

RESUMO

By using the flip-chip bonding technology, a high performances 3D-integrated silicon photonics receiver is demonstrated. The receiver consists of a high-speed germanium-silicon (Ge-Si) photodetector (PD) and a commercial linear transimpedance amplifiers (TIA). The overall 3 dB bandwidth of the receiver is around 38 GHz with appropriate gain. Based on this 3D-integrated receiver, the 56, 64, 90, 100 Gbit/s non-return-to-zero (NRZ) and 112, 128 Gbit/s four-level pulse amplitude (PAM-4) modulation clear openings of eye diagrams are experimentally obtained. The sensitivities of -10, -5.2 dBm and -6.6, -2.7 dBm were obtained for 112 Gbit/s NRZ and 160 Gbit/s PAM-4 at hard-decision forward err correction (HD-FEC,3.8 × 10-3) and KP4 forward err correction (KP4-FEC,2 × 10-4) threshold, respectively. Additionally, the lowest power consumption of this receiver is about 1.2 pJ/bit, which implies its huge potential for short-reach data center applications.

18.
Toxics ; 11(2)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36850972

RESUMO

To investigate the heavy metal contamination of soil in a uranium mining area in northern Guangdong, a physicochemical evaluation method was used to evaluate the contaminated soil near the pit and tailings pond of the uranium mining area, determine its heavy metal content and evaluate its ecological risk using the Nemerow integrated contamination index, ground accumulation index and potential ecological risk index. The results show that the average content of nine heavy metal elements in the soil of the uranium mining area exceeds the background value of red soil in Guangdong Province. Three pollution evaluation indices all indicate that Cd, As and U have serious pollution and high ecological risk, while the remaining elements are weakly polluted and the potential ecological risk of the six sampling sites all show very strong risk. On this basis, soil ecotoxicity was evaluated using ostracods (Cypridopsis vidua and Heterocypris sp.), Vibrio fischeri and Vicia faba L. Higher concentrations of heavy metals at individual sites (T1, T2, P2) resulted in higher mortality of ostracods, higher inhibition of Vibrio fischeri luminescence and a significant reduction in germination and pigmentation of broad beans. The results of the biotoxicity evaluation were consistent with the results of the physicochemical evaluation, allowing for a more direct and comprehensive evaluation of the ecotoxic effects of uranium and heavy metals in the mine soils.

20.
J Asian Nat Prod Res ; 25(9): 819-833, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36632044

RESUMO

This paper describes a rare phenomenon of multi-conformers caused by conformational change of A-ring in the C18- and C19- N-dealkyl diterpenoid alkaloids. The possible reasons for the generation of multiple conformational isomers are complex, which could be affected by the substituents at C-1, C-3, C-13, C-14, and C-15, pH, solvents, the intramolecular hydrogen bond between 1α-OCH3/1α-OH and N-H groups, acid-base treatment, preparation methods, and work-up procedures.


Assuntos
Aconitum , Alcaloides , Diterpenos , Alcaloides/química , Diterpenos/química , Aconitum/química , Estrutura Molecular
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