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1.
Cureus ; 16(7): e63893, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39099937

RESUMO

Aim The aim of this study was to evaluate the effectiveness of 5% eutectic mixture of local anesthetics (EMLA) cream and 20% benzocaine gel in reduction of pain during rubber dam clamp placement in the treatment of non-carious cervical lesions (NCCLs). Methodology In this split-mouth single-blind randomized clinical trial, 50 adult participants were selected from the outpatient department. The test group was treated using 5% EMLA cream for three minutes, and visual analog scale (VAS) scores were recorded. The comparison group was treated using 20% benzocaine gel and procedure was repeated as that in the test group. After recording the VAS scores, NCCLs in both the groups were restored using composite restoration. Results In the included 50 participants, 70% were males, with an age group of 31-67 years. The mean VAS score at 3 minutes in EMLA group was significantly lower than that in benzocaine group. Conclusion Application of 5% EMLA cream for 3 minutes showed greater pain reduction during rubber dam clamp placement as compared to 20% benzocaine gel in adult patients with NCCLs.

2.
J Mater Chem B ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39110475

RESUMO

Two dimensional (2D) nanosheets of MoS2 were succesfully produced by an exfoliation process in aqueous media with the support from peptides and sonication. The exfoliation process assisted by uncapped MoSBP1 peptides was found to have enhanced efficiency in comparison to the capped counterpart. MoS2 nanosheets obtained using uncapped MoSBP1 have thinner structures containing one layer of MoS2, while in capped version of peptides, MoS2 nanosheets tend to form multilayer (up to 4) structures of exfoliated sheets. Molecular dynamics simulations indicate that inter-sheet gaps generated by sonication in MoS2 nanostacks cannot be maintained by water only; the gaps closed after ∼11 ns. Both capped CMoSBP1 and uncapped MoSBP1 were seen to spontaneously insert into the gap in nanostacks of MoS2 and they can ultimately maintain the inter-sheet gap for longer (≥20 ns). Potential of mean force profiles for the association of two MoS2 nanosheets decorated with CMoSBP1 and MoSBP1 versions of peptides revealed that uncapped MoSBP1 peptides provide good protection from MoS2 nanosheet re-unification. Such protection can prevent the nanosheets from reassociation and subsequent aggregation, whereas the capped CMoSBP1 peptides can offer protection, but over a shorter range. These simulation results could explain the experimental observation of greater efficiency of exfoliation in uncapped MoSBP1 peptides.

3.
J Conserv Dent Endod ; 27(6): 634-638, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38989487

RESUMO

Context: An unfavorable event that can hinder endodontic treatment and affect the outcome of root canal treatment is the separation of endodontic instruments. Endodontic instrument separation can occur due to clinical or metallurgical factors. Friction between the ultrasonic tip and the remaining dentin generates heat, which is subsequently transferred to the external root surface. Elevated temperatures exceeding 10°C above body temperature for more than a minute may result in injury to periodontal or bone tissue. Aim: The aim of this study was to evaluate and compare temperature rise on the external root surface of teeth during retrieval of broken NiTi instrument using two different ultrasonic tips and two power settings. Materials and Methods: In each group, a sample size of 8 was sufficient to attain a statistical power exceeding 90%, enabling the detection of a minimum mean difference of 0.9204 (delta) through a one-way ANOVA test at a 95% confidence level (alpha 0.05). After access opening and working length determination, samples were randomly distributed into two groups - Group 1 (A and B) - ProUltra tip at high and low power settings and Group 2 (A and B) - Cric Dental IR3 at high and low power settings. The temperature rise was measured using K-type thermocouple thermometer. The comparisons were analyzed using the Kruskal-Wallis test with pairwise comparisons using the Dunn's test. Results: Group 1A and Group 1B resulted in lower heat generation compared to Group 2A and 2B and its difference was statistically significant (P < 0.05). Minimum temperature rise is seen in the ProUltra group at lower power settings (Group 1A) at the apical level and maximum temperature rise is seen in the Cric Dental IR3 group at higher power settings (Group 2B) at the middle third level. Conclusion: It was found that there is a significant temperature rise seen when ultrasonic tips are used for the retrieval of separated files, especially at higher power settings. The ProUltra tip demonstrated the lowest temperature rise at lower power settings, particularly at the apical level, whereas the IR3 Cric Dental tip exhibited the highest temperature rise, notably at higher power settings and the middle third level.

4.
Interv Neuroradiol ; : 15910199241264328, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39051591

RESUMO

INTRODUCTION: Thrombectomy for medium vessel occlusion is a topic of great interest. We describe a single-center experience with the Penumbra 3-MAX aspiration catheter in stroke thrombectomy of medium vessel occlusion(MeVO). We investigated the use of 3-MAX as a de-novo first pass catheter and as a rescue aspiration device following attempted thrombectomy with other devices. This is the first description of the first pass effect and successful recanalization rate of the 3-MAX catheter in de-novo vs. rescue use of this catheter. METHODS: From January 2017 to January 2023, 84 patients underwent mechanical thrombectomy with use of a Penumbra 3MAX aspiration catheter at our comprehensive stroke center. Patient charts were retrospectively reviewed. Primary efficacy outcome was successful recanalization following mechanical thrombectomy. Primary safety outcome was intracerebral hemorrhage. RESULTS: A total of 84 patients underwent MT with the 3MAX device. It was used as a de novo catheter in 27(32.1%) and as a rescue catheter in 57(67.9%) patients. 35(41.6%) patients achieved angiographic TICI grade ≥ 2c. De novo 3MAX use led to 68.18% successful recanalization and rescue use led to 72.22% recanalization (p = 0.67) as measured by TICI score of 2c or better. Parenchymal intracerebral hemorrhages (PH) were present in 8 patients (9.5%). CONCLUSION: The Penumbra 3MAX catheter is safe and effective when used as a first pass or a rescue device in mechanical thrombectomy. We found similar rates of successful recanalization and minimal hemorrhagic risk when comparing the 3MAX as a rescue or de novo aspiration catheter.

5.
Indian J Thorac Cardiovasc Surg ; 40(3): 327-331, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38681723

RESUMO

Percutaneous transluminal mitral commissurotomy (PTMC) has become the standard of care for severe mitral stenosis with favorable anatomy. Although the complications have reduced over the years, the need for emergency surgical rescue persists. This study evaluates the outcomes of surgical rescue performed within 24 h of undergoing PTMC from 1 January 2013 to 31 December 2019. Out of 2259 PTMC patients, 22 patients (< 1%) required rescue mitral valve surgery. Out of 22 patients, 17 patients (77.27%) developed mitral regurgitation; five patients (22.7%) had cardiac tamponade. Mitral valve replacement was performed in 20 patients (90.9%), while two patients (9.1%) underwent mitral valve repair. Cardiac tamponade was secondary to injury of the left atrium (9.1%), left ventricle (4.5%), and right ventricle (9.1%). Concomitant tricuspid valve repair was done in three patients (13.6%). Intraoperatively, anterior mitral leaflet tear was seen in 68.2% while posterior mitral leaflet tear was noted in 9.1%. Postoperatively, three patients (13.6%) required prolonged ventilation, incidence of stroke was 4.5% (n = 1), and in-hospital mortality was 4.5% (n = 1). Intra-aortic balloon pump was used in three patients (13.6%), preoperatively. We conclude that post-PTMC complications are rare, but they require urgent surgical intervention.

6.
Ann Neurol ; 95(5): 858-865, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38481016

RESUMO

OBJECTIVE: There are limited data evaluating the optimum blood pressure (BP) goal post mechanical thrombectomy (MT) and its effect on outcomes of patients with large vessel occlusions (LVO). The objective of this study was to compare the efficacy and safety of intensive versus conventional BP control after reperfusion with MT via a systematic review and meta-analysis of randomized controlled trials (RCTs). METHODS: We searched PubMed and Embase to obtain articles related to BP control post MT through September 2023. The primary outcome was functional independence (modified Rankin Scale [mRS] 0-2) at 3 months, while secondary outcomes included excellent outcome (mRS 0-1), symptomatic intracranial hemorrhage (sICH), and mortality. RESULTS: Four RCTs with 1,566 patients (762 randomized into intensive BP control vs. 806 randomized into conventional BP control) were included. Analysis showed that there was a lower likelihood of functional independence (mRS 0-2: odds ratio [OR]: 0.68, 95% confidence interval [CI] 0.51-0.91, p = 0.009) in the more intensive treatment group compared with the conventional treatment group. There was no statistically significant difference in achieving excellent outcome (mRS0-1: OR: 0.82, 95% CI: 0.63-1.07; p = 0.15), risk of sICH or mortality. INTERPRETATION: This systematic review and meta- analysis Indicates that in patients who achieved successful MT for acute ischemic stroke with LVO, intensive BP control was associated with a lower likelihood of functional independence at 3 months without significant difference in likelihood of achieving excellent outcome, sICH risk, or mortality. ANN NEUROL 2024;95:858-865.


Assuntos
Pressão Sanguínea , Procedimentos Endovasculares , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Pressão Sanguínea/fisiologia , Procedimentos Endovasculares/métodos , AVC Isquêmico/terapia , AVC Isquêmico/cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Trombectomia/métodos , Resultado do Tratamento
7.
Cureus ; 16(2): e54534, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38516433

RESUMO

Schizencephaly is a rare congenital anomaly characterized by the formation of abnormal clefts in the brain. Despite the association of psychotic symptoms with various brain abnormalities or insults, their occurrence in individuals with schizencephaly is relatively infrequent. The association of bipolar disorder, with or without psychosis, with schizencephaly is rarer. A systematic search on PubMed using "Schizencephaly AND Bipolar Disorder" yielded only four case studies specifically addressing the connection between these two conditions. Here, we present a case of a 22-year-old male patient with a history of childhood seizures who developed first episode psychosis along with manic symptoms and was found to have closed-lip schizencephaly.

8.
J Mater Chem B ; 12(20): 4824-4832, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38410880

RESUMO

Liquid-phase exfoliation using biomolecules in aqueous solution is a promising approach to obtain high quality 2D nanosheets. For example, the well-studied graphene-binding peptide, P1 (sequence HSSYWYAFNNKT), has been previously investigated and shown to have a good ability to exfoliate graphene sheets in aqueous conditions under sonication, maintaining colloidal stability. Building on this, the biomolecular exfoliant and assembly motif (BEAM) peptide, that features a graphene-binding domain at one end and a hexagonal boron nitride (h-BN) binding domain at the other, separated by a 10-carbon fatty acid chain in the centre, is shown to exfoliate graphene sheets from bulk graphite in aqueous media. An in-depth examination of the ability of the BEAM to both facilitate sheet exfoliation under sonication conditions and also maintain colliodal stability is provided through molecular dynamics simulations. These findings open new possibilities for designing multi-functional molecules that can both exfoliate and organise 2D materials into heterostructures under ambient conditions in aqueous media.


Assuntos
Grafite , Simulação de Dinâmica Molecular , Peptídeos , Grafite/química , Peptídeos/química , Compostos de Boro/química , Tamanho da Partícula
9.
Nature ; 626(7999): 464-465, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38317001
10.
Front Neurol ; 15: 1352310, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38343711

RESUMO

Importance: Stroke-to-recanalization time is a strong predictor of outcomes in anterior circulation large-vessel occlusion (LVO). The authors aimed to evaluate functional outcomes in early (<6 h) vs. late (6-24 h) time windows for thrombectomy-treated basilar artery occlusions. Methods: Patients were derived from the Posterior Circulation Ischemic Stroke Evaluation: Analyzing Radiographic and Intra-procedural Predictors of Mechanical Thrombectomy (PC-SEARCH) Registry and retrospectively analyzed early and late basilar artery thrombectomy time windows cohorts. Patients were dichotomized based on the last known well and correlated to 90-day functional outcomes (mRS 0-3). A multiple logistic regression analysis was performed. Results: A total of 405 patients were included in this study: 216 and 189 patients in the early and late time windows, respectively. Baseline demographic, stroke, radiographic, and intraprocedural characteristics were similar between the groups. A total of 99 (46%) and 79 (42%) patients in the early and late time windows, respectively, achieved favorable functional outcomes at 90 days (p = 0.41), and multiple logistic regression analysis did not reveal differences between cohorts (OR: 0.74; 95% CI: 0.46-1.19; p = 0.22). Symptomatic hemorrhage (7% vs. 5%; p = 0.69) and neurological complications (8% vs. 9%; p = 0.83) were similar between the groups; however, hospital complications were more common in the early time window cohort (22% vs. 13%; p = 0.01). Conclusion: The early and late thrombectomy time windows can achieve similar rates of 90-day favorable functional outcomes. However, timely thrombectomy influences the likelihood of achieving excellent functional outcomes (mRS ≤ 2) within the early time window.

11.
Sci Rep ; 14(1): 3071, 2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321149

RESUMO

Low HDL levels are associated with an increased stroke incidence and worsened long-term outcomes. The aim of this study was to assess the relationship between HDL levels and long-term stroke outcomes in the Arab population. Patients admitted to the Qatar Stroke Database between 2014 and 2022 were included in the study and stratified into sex-specific HDL quartiles. Long-term outcomes included 90-Day modified Rankin Score (mRS), stroke recurrence, and post-stroke cardiovascular complications within 1 year of discharge. Multivariate binary logistic regression analyses were performed to identify the independent effect of HDL levels on short- and long-term outcomes. On multivariate binary logistic regression analyses, 1-year stroke recurrence was 2.24 times higher (p = 0.034) and MACE was 1.99 times higher (p = 0.009) in the low-HDL compared to the high-HDL group. Mortality at 1 year was 2.27-fold in the low-normal HDL group compared to the reference group (p = 0.049). Lower sex-specific HDL levels were independently associated with higher adjusted odds of 1-year post-stroke mortality, stroke recurrence, and MACE (p < 0.05). In patients who suffer a stroke, low HDL levels are associated with a higher risk of subsequent vascular complication.


Assuntos
Árabes , Acidente Vascular Cerebral , Masculino , Feminino , Humanos , HDL-Colesterol , Acidente Vascular Cerebral/epidemiologia , Catar , Fatores de Risco
12.
Neurohospitalist ; 14(1): 95-98, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38235021

RESUMO

We present a case report of a previously healthy 29 year old woman who developed thromboembolic events in rapid fashion after a recent orthopedic surgery. This case highlights the importance of understanding risk factors for clot formation even in those who had no prior events, the efficacy of novel aspiration techniques to remove emboli, and how rapid triaging of acute symptoms can lead to the best outcomes. She presented to the emergency department with shortness of breath and was found to have a large bilateral pulmonary embolus. She was given intravenous thrombolysis. Shortly after, she developed aphasia and right-sided weakness and was taken emergently for mechanical thrombectomy of a left middle cerebral artery occlusion. She was later found to have a patent foramen ovale and a highly mobile right atrial thrombus which was aspirated. Further evaluation revealed right lower extremity peroneal and popliteal deep venous thrombi. She was placed on anticoagulation, made a full clinical recovery, and was discharged home. Prompt recognition of symptoms, efficient in-hospital work flow, and a multidisciplinary approach led to an outstanding outcome in this young patient.

13.
J Chem Phys ; 159(22)2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38084812

RESUMO

Two-dimensional ferroic materials exhibit a variety of functional properties that can be tuned by temperature and pressure. CuInP2S6 is a layered material that is ferrielectric at room temperature and whose properties are a result of the unique structural arrangement of ordered Cu+ and In3+ cations within a (P2S6)4- anion backbone. Here, we investigate the effect of hydrostatic pressure on the structure of CuInP2S6 single crystals through a detailed Raman spectroscopy study. Analysis of the peak frequencies, intensities, and widths reveals four high pressure regimes. At 5 GPa, the material undergoes a monoclinic-trigonal phase transition. At higher pressures (5-12 GPa), we see Raman peak sharpening, indicative of a change in the electronic structure, followed by an incommensurate phase between 12 and 17 GPa. Above 17 GPa, we see evidence for bandgap reduction in material. The original state of the material is fully recovered upon decompression, showing that hydrostatic pressure could be used to tune the electronic and ferrielectric properties of CuInP2S6.

14.
BJPsych Bull ; : 1-6, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37947128

RESUMO

Liaison psychiatrists have identified that conducting capacity assessments in general hospital patients with alcohol-related brain damage (ARBD) can be challenging. This educational article uses the fictitious case of a man with ARBD, alcohol dependence and significant self-neglect, focusing on assessment of his capacity to decide about moving into a care home on discharge. We provide an overview of clinical, legal and ethical literature relevant to decision-making and capacity assessment in individuals with ARBD, with the aim of guiding clinicians approaching complex capacity assessments.

15.
J Conserv Dent Endod ; 26(4): 366-376, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37705554

RESUMO

Context: Adjuvant use of platelet-rich fibrin (PRF) in many areas of dentistry is well documented. However, its role in periapical surgery remains contested which requires further clarification by a higher level of evidence. Aim: The objective of this systematic review was to evaluate the effect of PRF on periapical surgery using meta-analysis. Materials and Methods: A comprehensive literature search was conducted in PUBMED, Cochrane Central Register of Controlled Trials, SCIENCE DIRECT, and GOOGLE SCHOLAR for randomized controlled trials (RCT) published until May 2021. Meta-analysis was performed for comparisons of baseline (pretreatment) versus posttreatment values for different measurement parameters (postoperative pain, peri apical healing both qualitatively and quantitatively). The risk of bias in all the included trials was assessed after the recommendations of the Cochrane Handbook for Systematic Reviews of Interventions. Results: Among the 356 eligible articles found in the initial search, 10 RCTs from 2011 through 2021 were included. Qualitative analysis of all the included studies showed that PRF may play a positive role in bone healing, reduction in periapical lesions, and enhancing quality of life using different imaging modalities. The results of the meta-analysis indicated a significant reduction in postoperative pain when PRF was used (standard mean difference [SMD] = 0.515; 95% confidence interval [CI] = 0.061- 0.969;P = 0.026; I 2 = 0%). However, there was no statistically significant association observed while evaluating peri apical bone healing both qualitatively (odds ratio [OR] = 1.427; 95% CI = 0.309-6.584; P = 0.648) and quantitatively measured by Cone beam computed tomography (SMD = -0.264; 95% CI = -0.974-0.447;P = 0.454) between PRF and control group. Conclusions: Considering the notable benefits demonstrated by use of PRF, it may be considered as a valuable adjunct in periapical surgery. However, more high-quality trials are necessary to assess the exact role of PRF.

16.
Nanomaterials (Basel) ; 13(15)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37570495

RESUMO

The first observation of ultraviolet surface-enhanced Raman scattering (UV-SERS) was 20 years ago, yet the field has seen a slower development pace than its visible and near-infrared counterparts. UV excitation for SERS offers many potential advantages. These advantages include increased scattering intensity, higher spatial resolution, resonance Raman enhancement from organic, biological, and semiconductor analytes, probing UV photoluminescence, and mitigating visible photoluminescence from analytes or substrates. One of the main challenges is the lack of readily accessible, effective, and reproducible UV-SERS substrates, with few commercial sources available. In this review, we evaluate the reported UV-SERS substrates in terms of their elemental composition, substrate morphology, and performance. We assess the best-performing substrates with regard to their enhancement factors and limits of detection in both the ultraviolet and deep ultraviolet regions. Even though aluminum nanostructures were the most reported and best-performing substrates, we also highlighted some unique UV-SERS composition and morphology substrate combinations. We address the challenges and potential opportunities in the field of UV-SERS, especially in relation to the development of commercially available, cost-effective substrates. Lastly, we discuss potential application areas for UV-SERS, including cost-effective detection of environmentally and militarily relevant analytes, in situ and operando experimentation, defect engineering, development of materials for extreme environments, and biosensing.

17.
Indian J Thorac Cardiovasc Surg ; : 1-9, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37359507

RESUMO

Background: Patient prosthetic mismatch is a serious but avoidable complication of surgical aortic valve replacement (SAVR) complicated by a small aortic annulus. This study aims to compare early and midterm outcomes following aortic valve replacement (AVR) with a mono-leaflet (ML) valve and a bi-leaflet (BL) valve in a small aortic root. Methods and selection: From January 1st, 2017 to December 31st, 2019, 98 patients diagnosed with small aortic root underwent isolated aortic valve replacement with either TTK Chitra valve (Mono-leaflet/ ML group) or St. Jude medical valve (Bi-leaflet/ BL group) of size 17/ 19 mm. Echocardiography was analyzed from medical records and telephonic follow-up. Results: Baseline parameters were comparable. The ML group had 42 patients and the BL group had 56 patients. Aortic cross-clamp time, the incidence of severe patient prosthetic mismatch (p = 0.002) and mean, peak pressure gradients were high in the ML group. Duration of ventilation, intensive care unit (ICU) stay, the incidence of stroke, need for intra-aortic balloon pump, permanent pacemaker, dialysis, and left ventricular mass index in echocardiography were comparable between the two groups postoperatively. There was no early mortality in both group. Survival at the end of 5 years was 57 ± 14.4% in the ML group; 91.8 ± 4% in the BL group (p = 0.005). Univariate and multivariate analysis revealed elderly age as a risk factor for mortality. Conclusion: We conclude that aortic valve replacement without any root widening procedure, using a small-sized mechanical valve provides acceptable early outcomes. Bi-leaflet mechanical valves provide better hemodynamics and survival percentage.

19.
ACS Omega ; 8(1): 1597-1605, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36643551

RESUMO

Printing technologies offer an attractive means for producing low-cost surface-enhanced Raman spectroscopy (SERS) substrates with high-throughput methods. The development of these substrates is especially important for field-deployable detection of environmental contaminants. Toward this end, we demonstrate SERS-based substrates fabricated through aerosol jet printing of silver nanoparticles and graphene inks on Kapton films. Our printed arrays exhibited measurable intensities for fluorescein and rhodamine dyes down to concentrations of 10-7 M, with the highest SERS intensities obtained for four print passes of Ag nanoparticles. The substrates also exhibited an excellent shelf life, with little reduction in fluorescein intensities after 9 months of shelf storage. We also demonstrated the capability of our substrates to sense perfluoroalkyl substances (PFAS), the so-called forever chemicals that resist degradation due to their strong C-F bonds and persist in the environment. Interestingly, the addition of graphene to the Ag nanoparticles greatly enhanced the SERS intensity of the perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) molecules under basic conditions (pH ∼ 9) compared to that of fluorescein and rhodamine. We were able to successfully detect SERS spectra from nano- and picomolar (∼0.4 ppt) concentrations of PFOA and PFOS, respectively, demonstrating the viability of deploying our SERS sensors in the environment for the ultrasensitive detection of contaminants.

20.
ACS Nano ; 17(3): 2958-2967, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36689725

RESUMO

Layered Transition Metal Dichalcogenides (TMDs) are an important class of materials that exhibit a wide variety of optoelectronic properties. The ability to spatially tailor their expansive property-space (e.g., conduction behavior, optical emission, surface interactions) is of special interest for applications including, but not limited to, sensing, bioelectronics, and spintronics/valleytronics. Current methods of property modulation focus on the modification of the basal surfaces and edge sites of the TMDs by the introduction of defects, functionalization with organic or inorganic moieties, alloying, heterostructure formation, and phase engineering. A majority of these methods lack the resolution for the development of next-generation nanoscale devices or are limited in the types of functionalities useful for efficient TMD property modification. In this study, we utilize electron-beam patterning on monolayer TMDs (MoSe2, WSe2 and MoS2) in the presence of a pressure-controlled atmosphere of water vapor within an environmental scanning electron microscope (ESEM). A series of parametric studies show local optical and electronic property modification depending on acceleration voltage, beam current, pressure, and electron dose. The ultimate pattern resolution achieved is 67 ± 9 nm. Raman and photoluminescence spectroscopies coupled with Kelvin Probe Force Microscopy reveal electron dose-dependent p-doping in the patterned regions, which we attribute to functionalization from the products of water vapor radiolysis (oxygen and hydroxyl groups). The modulation of the work function through patterning matches well with Density Functional Theory modeling. Finally, post-functionalization of the patterned areas with an organic fluorophore demonstrates a robust method to achieve nanoscale functionalization with high fidelity.

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