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1.
Nature ; 593(7858): 211-217, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33981050

RESUMO

Advanced beyond-silicon electronic technology requires both channel materials and also ultralow-resistance contacts to be discovered1,2. Atomically thin two-dimensional semiconductors have great potential for realizing high-performance electronic devices1,3. However, owing to metal-induced gap states (MIGS)4-7, energy barriers at the metal-semiconductor interface-which fundamentally lead to high contact resistance and poor current-delivery capability-have constrained the improvement of two-dimensional semiconductor transistors so far2,8,9. Here we report ohmic contact between semimetallic bismuth and semiconducting monolayer transition metal dichalcogenides (TMDs) where the MIGS are sufficiently suppressed and degenerate states in the TMD are spontaneously formed in contact with bismuth. Through this approach, we achieve zero Schottky barrier height, a contact resistance of 123 ohm micrometres and an on-state current density of 1,135 microamps per micrometre on monolayer MoS2; these two values are, to the best of our knowledge, the lowest and highest yet recorded, respectively. We also demonstrate that excellent ohmic contacts can be formed on various monolayer semiconductors, including MoS2, WS2 and WSe2. Our reported contact resistances are a substantial improvement for two-dimensional semiconductors, and approach the quantum limit. This technology unveils the potential of high-performance monolayer transistors that are on par with state-of-the-art three-dimensional semiconductors, enabling further device downscaling and extending Moore's law.

2.
Nature ; 566(7744): 368-372, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30692651

RESUMO

The mechanical and electronic properties of two-dimensional materials make them promising for use in flexible electronics1-3. Their atomic thickness and large-scale synthesis capability could enable the development of 'smart skin'1,3-5, which could transform ordinary objects into an intelligent distributed sensor network6. However, although many important components of such a distributed electronic system have already been demonstrated (for example, transistors, sensors and memory devices based on two-dimensional materials1,2,4,7), an efficient, flexible and always-on energy-harvesting solution, which is indispensable for self-powered systems, is still missing. Electromagnetic radiation from Wi-Fi systems operating at 2.4 and 5.9 gigahertz8 is becoming increasingly ubiquitous and would be ideal to harvest for powering future distributed electronics. However, the high frequencies used for Wi-Fi communications have remained elusive to radiofrequency harvesters (that is, rectennas) made of flexible semiconductors owing to their limited transport properties9-12. Here we demonstrate an atomically thin and flexible rectenna based on a MoS2 semiconducting-metallic-phase heterojunction with a cutoff frequency of 10 gigahertz, which represents an improvement in speed of roughly one order of magnitude compared with current state-of-the-art flexible rectifiers9-12. This flexible MoS2-based rectifier operates up to the X-band8 (8 to 12 gigahertz) and covers most of the unlicensed industrial, scientific and medical radio band, including the Wi-Fi channels. By integrating the ultrafast MoS2 rectifier with a flexible Wi-Fi-band antenna, we fabricate a fully flexible and integrated rectenna that achieves wireless energy harvesting of electromagnetic radiation in the Wi-Fi band with zero external bias (battery-free). Moreover, our MoS2 rectifier acts as a flexible mixer, realizing frequency conversion beyond 10 gigahertz. This work provides a universal energy-harvesting building block that can be integrated with various flexible electronic systems.

3.
J Am Chem Soc ; 146(14): 10150-10158, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38557061

RESUMO

Electrons not only serve as a "reactant" in redox reactions but also play a role in "catalyzing" some chemical processes. Despite the significance and ubiquitousness of electron-induced chemistry, many related scientific issues still await further exploration, among which is the impact of molecular assembly. In this work, microscopic insights into the vital role of molecular assembly in tweaking the electron-induced surface chemistry are unfolded by combined scanning tunneling microscopy and density functional theory studies. It is shown that the selective dissociation of a C-Cl bond in 4,4″-dichloro-1,1':3',1''-terphenyl (DCTP) on Cu(111) can be efficiently triggered by an electron injection via the STM tip into the unoccupied molecular orbital. The DCTP molecules are embedded in different assembly structures, including its self-assembly and coassemblies with Br adatoms. The energy threshold for the C-Cl bond cleavage increases as more Br adatoms stay close to the molecule, indicative of the sensitive response of the electron-induced surface reactivity of the C-Cl bond to the subtle change in the molecular assembly. Such a phenomenon is rationalized by the energy shift of the involved unoccupied molecular orbital of DCTP that is embedded in different assemblies. These findings shed new light on the tuning effect of molecular assembly on electron-induced reactions and introduce an efficient approach to precisely steer surface chemistry.

4.
J Biochem Mol Toxicol ; 38(1): e23610, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38091339

RESUMO

Although epidemiological studies have evaluated the association between ambient air pollution and chronic kidney disease (CKD), the results remain mixed. To clarify the nature of the association, we conducted a comprehensive systematic review and meta-analysis to assess the global relationship between air pollution and CKD. The Web of Science, PubMed, Embase and Cochrane Library databases systematically were searched for studies published up to July 2023 and included 32 studies that met specific criteria. The random effects model was used to derive overall risk estimates for each pollutant. The meta-analysis estimated odds ratio (ORs) of risk for CKD were 1.42 (95% confidence interval [CI]: 1.31-1.54) for each 10 µg/m3 increase in PM2.5 ; 1.20 (95% CI: 1.14-1.26) for each 10 µg/m3 increase in PM10 ; 1.07 (95% CI: 1.05-1.09) for each 10 µg/m3 increase in NO2 ; 1.03 (95% CI: 1.02-1.03) for each 10 µg/m3 increase in NOX ; 1.07 (95% CI: 1.01-1.12) for each 1 ppb increase in SO2 ; 1.03 (95% CI: 1.00-1.05) for each 0.1 ppm increase in CO. Subgroup analysis showed that this effect varied by gender ratio, age, study design, exposure assessment method, and income level. Furthermore, PM2.5 , PM10 , and NO2 had negative effects on CKD even within the World Health Organization-recommended acceptable concentrations. Our results further confirmed the adverse effect of air pollution on the risk of CKD. These findings can contribute to enhance the awareness of the importance of reducing air pollution among public health officials and policymakers.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Insuficiência Renal Crônica , Humanos , Poluentes Atmosféricos/efeitos adversos , Material Particulado/efeitos adversos , Dióxido de Nitrogênio/análise , Exposição Ambiental/efeitos adversos , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/induzido quimicamente
5.
Clin Oral Implants Res ; 35(2): 220-229, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38033198

RESUMO

OBJECTIVE: Optimal implant planning and placement allows the prosthesis to be well designed to achieve a satisfactory aesthetic and functional outcome. We aimed to compare deviations between implant planning and placement with the assistance of dynamic computer-assisted implant surgery (d-CAIS) or autonomous robotic computer-assisted implant surgery (r-CAIS) methods in a clinical setting. METHODS: The retrospective analysis of medical records between 2021 July and 2022 December was conducted to compare the implantation accuracy of the d-CAIS and r-CAIS system in partially edentulous patients through cone-beam computed tomography. Patient-reported outcomes (PROs) were recorded using a visual analogue scale (VAS). The Kolmogorov-Smirnov test was used to check the data distribution. Student's t-test or Mann-Whitney U-test was used as appropriate, with a defined significant difference (p < .05). RESULTS: Seventy-seven patients were analysed (124 implants), with 38 patients (62 implants) in the d-CAIS group and 39 patients (62 implants) in the r-CAIS group. The differences between d-CAIS and r-CAIS were 4.09 ± 1.79° versus 1.37 ± 0.92° (p < .001) in angular deviation; 1.25 ± 0.54 versus 0.68 ± 0.36 mm (p < .001) in coronal global deviation; 1.39 ± 0.52 versus 0.69 ± 0.36 mm (p < .001) in apical global deviation; the results of the PROMs showed no statistical difference between the two groups. CONCLUSIONS: r-CAIS allows more accurate implant placement than the d-CAIS technology. And both groups achieved overall satisfactory outcomes via VAS (Chinese Clinical Trial Registry ChiCTR2300072004).


Assuntos
Implantes Dentários , Procedimentos Cirúrgicos Robóticos , Cirurgia Assistida por Computador , Humanos , Implantação Dentária Endóssea/métodos , Estudos Retrospectivos , Cirurgia Assistida por Computador/métodos , Computadores , Tomografia Computadorizada de Feixe Cônico , Desenho Assistido por Computador , Imageamento Tridimensional
6.
Nucleic Acids Res ; 50(8): 4414-4435, 2022 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-35390160

RESUMO

Mammalian early epiblasts at different phases are characterized by naïve, formative, and primed pluripotency states, involving extensive transcriptome changes. Here, we report that deadenylase Cnot8 of Ccr4-Not complex plays essential roles during the transition from naïve to formative state. Knock out (KO) Cnot8 resulted in early embryonic lethality in mice, but Cnot8 KO embryonic stem cells (ESCs) could be established. Compared with the cells differentiated from normal ESCs, Cnot8 KO cells highly expressed a great many genes during their differentiation into the formative state, including several hundred naïve-like genes enriched in lipid metabolic process and gene expression regulation that may form the naïve regulation networks. Knockdown expression of the selected genes of naïve regulation networks partially rescued the differentiation defects of Cnot8 KO ESCs. Cnot8 depletion led to the deadenylation defects of its targets, increasing their poly(A) tail lengths and half-life, eventually elevating their expression levels. We further found that Cnot8 was involved in the clearance of targets through its deadenylase activity and the binding of Ccr4-Not complex, as well as the interacting with Tob1 and Pabpc1. Our results suggest that Cnot8 eliminates naïve regulation networks through mRNA clearance, and is essential for naïve-to-formative pluripotency transition.


Assuntos
Células-Tronco Embrionárias , Regulação da Expressão Gênica , Fatores de Transcrição , Animais , Camundongos , Diferenciação Celular/genética , Células-Tronco Embrionárias/metabolismo , Mamíferos/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição/metabolismo , Transcriptoma
7.
Proc Natl Acad Sci U S A ; 118(32)2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34353912

RESUMO

Technology advancements in history have often been propelled by material innovations. In recent years, two-dimensional (2D) materials have attracted substantial interest as an ideal platform to construct atomic-level material architectures. In this work, we design a reaction pathway steered in a very different energy landscape, in contrast to typical thermal chemical vapor deposition method in high temperature, to enable room-temperature atomic-layer substitution (RT-ALS). First-principle calculations elucidate how the RT-ALS process is overall exothermic in energy and only has a small reaction barrier, facilitating the reaction to occur at room temperature. As a result, a variety of Janus monolayer transition metal dichalcogenides with vertical dipole could be universally realized. In particular, the RT-ALS strategy can be combined with lithography and flip-transfer to enable programmable in-plane multiheterostructures with different out-of-plane crystal symmetry and electric polarization. Various characterizations have confirmed the fidelity of the precise single atomic layer conversion. Our approach for designing an artificial 2D landscape at selective locations of a single layer of atoms can lead to unique electronic, photonic, and mechanical properties previously not found in nature. This opens a new paradigm for future material design, enabling structures and properties for unexplored territories.

8.
J Obstet Gynaecol Res ; 50(3): 485-493, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38097390

RESUMO

OBJECTIVE: This study aimed to evaluate the effect of vaginal dilation therapy on vaginal length, vaginal stenosis, vaginal elasticity, and sexual function of endometrial cancer patients treated with radiotherapy after surgery. METHODS: A total of 117 women were enrolled in this study. They received 6 months of vaginal dilation therapy. We evaluated their vaginal length, vaginal diameter, vaginal elasticity, and sexual function before radiotherapy, after radiotherapy, and after 6 months of vaginal dilation therapy. Their vaginal condition was assessed by customized vaginal dilating molds. Their sexual function was assessed by female sexual function index. The SPSS 25 software was used to analyze all the data. RESULTS: According to multivariate analysis, vaginal diameter (ß = 0.300, 95% CI [0.217-1.446], p = 0.010) and sexual intercourse frequency before diagnosis (ß = 0.424, 95% CI [0.164-0.733], p = 0.006) were significantly correlated with female sexual function after radiotherapy. Vaginal dilation therapy helped increase vaginal length, improve vaginal stenosis and sexual function (p < 0.05), though most of the figures at the end of the intervention did not fully return to those before radiotherapy. Noticeably, vaginal dilation therapy was ineffective in improving vaginal elasticity and the incidence rate of female sexual dysfunction (p > 0.05). Moreover, patients with medium or good vaginal elasticity benefited more from vaginal dilation therapy than patients with poor vaginal elasticity (p < 0.05). CONCLUSION: Vaginal dilation therapy should be carried out timely and preventatively in endometrial cancer patients treated with radiotherapy after surgery to improve their vaginal condition and sexual function.


Assuntos
Neoplasias do Endométrio , Transtornos Mentais , Humanos , Feminino , Constrição Patológica/terapia , Dilatação/efeitos adversos , Vagina/cirurgia , Neoplasias do Endométrio/radioterapia , Neoplasias do Endométrio/cirurgia
9.
J Obstet Gynaecol ; 44(1): 2317387, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38466132

RESUMO

BACKGROUND: Cervical cancer survivors can experience vaginal length shortening, vaginal stenosis, vaginal elasticity deterioration, sexual frequency reduction and sexual dysfunction. This prospective, uncontrolled, monocentric clinical interventional study aimed to evaluate the effect of vaginal dilation therapy on vaginal condition and sexual function of cervical cancer survivors who had not received timely vaginal dilation. METHODS: A total of 139 patients completed the study. They received 6 months of vaginal dilation therapy. We evaluated their vaginal elasticity, vaginal diameter, vaginal length and sexual function before and after vaginal dilation therapy. Their vaginal conditions were evaluated by customised vaginal moulds, and the sexual function was assessed by female sexual function index. The SPSS 25 software was used to analyse all the data. RESULTS: Age, vaginal diameter and sexual intercourse frequency before diagnosis were significantly associated with female sexual dysfunction of the patients after cancer treatment. Vaginal dilation therapy improved vaginal stenosis, vaginal length and sexual function in all the patients; however, the vaginal elasticity and incidence of sexual dysfunction did not improve significantly. Sexual intercourse frequency before diagnosis, vaginal elasticity, time interval from last treatment and treatment modalities were significantly associated with the change in female sexual function index score before and after vaginal dilation therapy. Patients with a time interval from the last treatment less than 24 months or those who had moderate or good vaginal elasticity, benefitted more from vaginal dilatation therapy. CONCLUSIONS: Cervical cancer survivors who had not received timely vaginal dilation still benefitted from vaginal dilation therapy, irrespective of the treatment methods they received. Moreover, vaginal dilation therapy should be performed as early as possible after cervical cancer treatment.


Cervical cancer survivors can experience vaginal condition deterioration and sexual dysfunction after treatment. Vaginal dilation can help improve vaginal stenosis, vaginal length and sexual function of these patients. However, some medical institutions in China do not provide timely vaginal dilation for this population. This study aimed to explore whether vaginal dilation was still effective for cervical cancer survivors who had not received timely vaginal dilation. The results showed that these patients still benefitted from vaginal dilation, irrespective of the treatment methods they received. Patients with a time interval from the last treatment less than 24 months or those who had moderate or good vaginal elasticity, benefitted more from vaginal dilation. The findings of the study is an indication to developing countries that more attention should be given to sexual issue of cervical cancer survivors in clinical practice, and vaginal dilation therapy should be performed promptly after treatment.


Assuntos
Sobreviventes de Câncer , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/terapia , Vagina , Constrição Patológica/etiologia , Constrição Patológica/terapia , Dilatação/efeitos adversos , Estudos Prospectivos , Elasticidade
10.
Stroke ; 54(7): 1920-1929, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37021568

RESUMO

Ischemic stroke profoundly influences the peripheral immune system, which responds quickly to brain ischemia and participates in the evolution of poststroke neuroinflammation, while a period of systemic immunosuppression ensues. Poststroke immunosuppression brings harmful consequences, including increased infection rates and escalated death. As the most abundant cell population in the fast-responding innate immune system, myeloid cells including neutrophils and monocytes play an indispensable role in systemic immunosuppression after stroke. The change in myeloid response after stroke can be regulated by circulating DAMPs (damage-associated molecular patterns) and neuromodulatory mechanisms, which contain sympathetic nervous system, hypothalamic-pituitary-adrenal, and parasympathetic nervous system. In this review, we summarize the emerging roles and newly identified mechanisms underlying myeloid cell response in poststroke immunosuppression. Deeper understanding of the above points may pave the way for future development of novel therapeutic strategies to treat poststroke immunosuppression.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Humanos , Terapia de Imunossupressão , Células Mieloides , Sistema Imunitário
11.
J Am Chem Soc ; 145(25): 13531-13536, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37314227

RESUMO

Molecular Sierpinski triangles (STs), a family of elegant and well-known fractals, can be prepared on surfaces with atomic precision. Up to date, several kinds of intermolecular interactions such as hydrogen bond, halogen bond, coordination, and even covalent bond have been employed to construct molecular STs on metal surfaces. Herein a series of defect-free molecular STs have been fabricated via electrostatic attraction between potassium cations and electronically polarized chlorine atoms in 4,4″-dichloro-1,1':3',1″-terphenyl (DCTP) molecules on Cu(111) and Ag(111). The electrostatic interaction is confirmed both experimentally by scanning tunneling microscopy and theoretically by density functional theory calculations. These findings illustrate that electrostatic interaction can serve as an efficient driving force to construct molecular fractals, which enriches our toolbox for the bottom-up fabrication of complex functional supramolecular nanostructures.

12.
BMC Med ; 21(1): 405, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37880716

RESUMO

BACKGROUND: Most of superficial soft-tissue masses are benign tumors, and very few are malignant tumors. However, persistent growth, of both benign and malignant tumors, can be painful and even life-threatening. It is necessary to improve the differential diagnosis performance for superficial soft-tissue masses by using deep learning models. This study aimed to propose a new ultrasonic deep learning model (DLM) system for the differential diagnosis of superficial soft-tissue masses. METHODS: Between January 2015 and December 2022, data for 1615 patients with superficial soft-tissue masses were retrospectively collected. Two experienced radiologists (radiologists 1 and 2 with 8 and 30 years' experience, respectively) analyzed the ultrasound images of each superficial soft-tissue mass and made a diagnosis of malignant mass or one of the five most common benign masses. After referring to the DLM results, they re-evaluated the diagnoses. The diagnostic performance and concerns of the radiologists were analyzed before and after referring to the results of the DLM results. RESULTS: In the validation cohort, DLM-1 was trained to distinguish between benign and malignant masses, with an AUC of 0.992 (95% CI: 0.980, 1.0) and an ACC of 0.987 (95% CI: 0.968, 1.0). DLM-2 was trained to classify the five most common benign masses (lipomyoma, hemangioma, neurinoma, epidermal cyst, and calcifying epithelioma) with AUCs of 0.986, 0.993, 0.944, 0.973, and 0.903, respectively. In addition, under the condition of the DLM-assisted diagnosis, the radiologists greatly improved their accuracy of differential diagnosis between benign and malignant tumors. CONCLUSIONS: The proposed DLM system has high clinical application value in the differential diagnosis of superficial soft-tissue masses.


Assuntos
Aprendizado Profundo , Neoplasias de Tecidos Moles , Humanos , Estudos Retrospectivos , Diagnóstico Diferencial , Neoplasias de Tecidos Moles/diagnóstico por imagem , Neoplasias de Tecidos Moles/patologia , Ultrassonografia , Sensibilidade e Especificidade
13.
Small ; 19(15): e2207342, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36605002

RESUMO

Hydrogen, a clean and flexible energy carrier, can be efficiently produced by electrocatalytic water splitting. To accelerate the sluggish hydrogen evolution reaction and oxygen evolution reaction kinetics in the splitting process, highly active electrocatalysts are essential for lowering the energy barriers, thereby improving the efficiency of overall water splitting. Combining the distinctive advantages of metal-organic frameworks (MOFs) with the physicochemical properties of 2D materials such as large surface area, tunable structure, accessible active sites, and enhanced conductivity, 2D MOFs have attracted intensive attention in the field of electrocatalysis. Different strategies, such as improving the conductivities of MOFs, reducing the thicknesses of MOF nanosheets, and integrating MOFs with conductive particles or substrates, are developed to promote the catalytic performances of pristine MOFs. This review summarizes the recent advances of pristine 2D MOF-based electrocatalysts for water electrolysis. In particular, their intrinsic electrocatalytic properties are detailly analyzed to reveal important roles of inherent MOF active centers, or other in situ generated active phases from MOFs responsible for the catalytic reactions. Finally, the challenges and development prospects of pristine 2D MOFs for the future applications in overall water splitting are discussed.

14.
Small ; 19(52): e2305201, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37635110

RESUMO

Multifunctional electrocatalysts are crucial to cost-effective electrochemical energy conversion and storage systems requiring mutual enhancement of disparate reactions. Embedding noble metal nanoparticles in 2D metal-organic frameworks (MOFs) are proposed as an effective strategy, however, the hybrids usually suffer from poor electrochemical performance and electrical conductivity in operating conditions. Herein, ultrafine Pt nanoparticles strongly anchored on thiophenedicarboxylate acid based 2D Fe-MOF nanobelt arrays (Pt@Fe-MOF) are fabricated, allowing sufficient exposure of active sites with superior trifunctional electrocatalytic activity for hydrogen evolution, oxygen evolution, and oxygen reduction reactions. The interfacial Fe─O─Pt bonds can induce the charge redistribution of metal centers, leading to the optimization of adsorption energy for reaction intermediates, while the dispersibility of ultrafine Pt nanoparticles contributes to the high mass activity. When Pt@Fe-MOF is used as bifunctional catalysts for water-splitting, a low voltage of 1.65 V is required at 100 mA cm-2 with long-term stability for 20 h at temperatures (65 °C) relevant for industrial applications, outperforming commercial benchmarks. Furthermore, liquid Zn-air batteries with Pt@Fe-MOF in cathodes deliver high open-circuit voltages (1.397 V) and decent cycling stability, which motivates the fabrication of flexible quasisolid-state rechargeable Zn-air batteries with remarkable performance.

15.
Phys Chem Chem Phys ; 25(2): 1006-1013, 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36533548

RESUMO

A molecular investigation of Cu-elimination and subsequent C-C coupling of DCTP (4,4''-dichloro-1,1':3',1''-terphenyl)-Cu organometallic (OM) polymers on Cu(111) is conducted by scanning tunneling microscopy and spectroscopy, revealing that the Cu adatoms embedded in the DCTP-Cu chains are located at the hollow and bridge sites on the Cu(111) surface. The difference in the catalytic activities of these surface sites leads to stepwise elimination of Cu adatoms in the OM chains. Moreover, the interchain interaction plays an important role in the Cu-elimination process of the DCTP-Cu chains as well. The interchain steric hindrance, on the one hand, induces the formation of Cu-eliminated intermediates that are scarcely observed in other Ullmann coupling systems, and on the other hand, promotes the cooperative Cu-elimination and C-C coupling of the OM segments in neighboring chains. These findings demonstrate the key role of the molecule-substrate and intermolecular interactions in mediating the reaction processes of the extended molecular systems on the surface.

16.
Sensors (Basel) ; 23(6)2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36991784

RESUMO

Given progress in water-quality analytical technology and the emergence of the Internet of Things (IoT) in recent years, compact and durable automated water-quality monitoring devices have substantial market potential. Due to susceptibility to the influence of interfering substances, which lowers measurement accuracy, existing automated online monitoring devices for turbidity, a key indicator of a natural water body, feature a single light source and are thus insufficient for more complicated water-quality measurement. The newly developed modularized water-quality monitoring device boasts dual light sources (VIS/NIR), capable of measuring the intensity of scattering, transmission, and reference light at the same time. Coupled with a water-quality prediction model, it can attain a good estimate for continuing monitoring of tap water (<2 NTU, error < 0.16 NTU, relative error < 19.6%) and environmental water samples (<400 NTU, error < 3.86 NTU, relative error < 2.3%). This indicates the optical module can both monitor water quality in low turbidity and provide water-treatment information alerts in high turbidity, thereby materializing automated water-quality monitoring.

17.
Sensors (Basel) ; 23(20)2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37896601

RESUMO

Anomaly detection tasks involving time-series signal processing have been important research topics for decades. In many real-world anomaly detection applications, no specific distributions fit the data, and the characteristics of anomalies are different. Under these circumstances, the detection algorithm requires excellent learning ability of the data features. Transformers, which apply the self-attention mechanism, have shown outstanding performances in modelling long-range dependencies. Although Transformer based models have good prediction performance, they may be influenced by noise and ignore some unusual details, which are significant for anomaly detection. In this paper, a novel temporal context fusion framework: Temporal Context Fusion Transformer (TCF-Trans), is proposed for anomaly detection tasks with applications to time series. The original feature transmitting structure in the decoder of Informer is replaced with the proposed feature fusion decoder to fully utilise the features extracted from shallow and deep decoder layers. This strategy prevents the decoder from missing unusual anomaly details while maintaining robustness from noises inside the data. Besides, we propose the temporal context fusion module to adaptively fuse the generated auxiliary predictions. Extensive experiments on public and collected transportation datasets validate that the proposed framework is effective for anomaly detection in time series. Additionally, the ablation study and a series of parameter sensitivity experiments show that the proposed method maintains high performance under various experimental settings.

18.
J Prosthet Dent ; 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36932022

RESUMO

A digital technique for transferring the maxillomandibular relationship using photogrammetry, an intraoral scanner, and a computer-aided design software program is described in a treatment involving immediate loading in a patient with mandibular edentulism. The edentulous mandible was located preoperatively in a centric occlusal relationship with a denture, and preoperative and postoperative cone beam computed tomography (CBCT) data were aligned and merged based on bone markers. This technique, which allows the transfer of the presurgical maxillomandibular relationship during the immediate loading procedure, is more objective, more straightforward, and faster than the conventional method.

19.
J Prosthet Dent ; 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36922296

RESUMO

This technical report describes a fully digital workflow for the design and fabrication of removable complete dentures in a single day. This technique integrates facial and intraoral scans, uses a computer-aided design software program to modify the orientation of the maxillary occlusal plane in the sagittal and frontal planes and evaluate the esthetics and finally produces complete dentures with a clinically acceptable design, simplifying the clinical workflow.

20.
Small ; 18(31): e2202301, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35713270

RESUMO

The electronic, optical, and magnetic properties of graphene nanoribbons (GNRs) can be engineered by controlling their edge structure and width with atomic precision through bottom-up fabrication based on molecular precursors. This approach offers a unique platform for all-carbon electronic devices but requires careful optimization of the growth conditions to match structural requirements for successful device integration, with GNR length being the most critical parameter. In this work, the growth, characterization, and device integration of 5-atom wide armchair GNRs (5-AGNRs) are studied, which are expected to have an optimal bandgap as active material in switching devices. 5-AGNRs are obtained via on-surface synthesis under ultrahigh vacuum conditions from Br- and I-substituted precursors. It is shown that the use of I-substituted precursors and the optimization of the initial precursor coverage quintupled the average 5-AGNR length. This significant length increase allowed the integration of 5-AGNRs into devices and the realization of the first field-effect transistor based on narrow bandgap AGNRs that shows switching behavior at room temperature. The study highlights that the optimized growth protocols can successfully bridge between the sub-nanometer scale, where atomic precision is needed to control the electronic properties, and the scale of tens of nanometers relevant for successful device integration of GNRs.

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