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1.
Clin Otolaryngol ; 2024 May 22.
Article in English | MEDLINE | ID: mdl-38773941

ABSTRACT

INTRODUCTION: Patients presenting with head and neck squamous cell carcinoma of unknown primary (HNSCCUP) remain challenging clinical scenarios as large variation exists in practices used to locate the primary. OBJECTIVE: The objective of this systematic review is to review of the literature and offer recommendations for oropharyngeal biopsies in HNSCCUP. METHOD: Pubmed, Medline and Embase were searched to identify studies from inception to October 2021. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were followed. RESULTS: A total of 483 articles were included and screened, 41 studies met the inclusion criteria, including over 3400 patients from the original articles (122 of these patients were reported on in two sequential articles by a single author - table 1) and 4 large metaanalyses including 1852 patients. The primary site identification rate following random biopsies or deep tissue biopsies is less than 5% in most studies. The mean detection rate following ipsilateral tonsillectomy is 34%; two pooled analyses indicate that the mean detection rate following tongue base mucosectomy is 64%, with this figure rising when the tonsils are negative. CONCLUSIONS: High level evidence is lacking, with heterogeneity in the reported studies. Published meta-analyses are based on retrospective data. There is little evidence supporting the practice of random/non-directed oropharyngeal biopsies. Available evidence supports palatine tonsillectomy and tongue base mucosectomy compared to deep tissue biopsies.

2.
ACS Nano ; 18(11): 8546-8554, 2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38456657

ABSTRACT

Monoclinic semiconducting ß-Ga2O3 has drawn attention, particularly because its thin film could be achieved via mechanical exfoliation from bulk crystals, which is analogous to van der Waals materials' behavior. For the transistor devices with exfoliated ß-Ga2O3, the channel direction becomes [010] for in-plane electron transport, which changes to vertical [100] near the source/drain (S/D) contact. Hence, anisotropic transport behavior is certainly worth to study but rarely reported. Here we achieve the vertical [100] direction electron mobility of 4.18 cm2/(V s) from Pt/ß-Ga2O3 Schottky diodes with various thickness via radio frequency-transmission line method (RF-TLM), which is recently developed. The specific contact resistivity (ρc) could also be estimated from RF-TLM, to be 4.72 × 10-5 Ω cm2, which is quite similar to the value (5.25 × 10-5 Ω cm2) from conventional TLM proving the validity of RF-TLM. We also fabricate metal-semiconductor field-effect transistors (MESFETs) to study anisotropic transport behavior and contact resistance (RC). RC-free [010] in-plane mobility appears as high as maximum ∼67 cm2/(V s), extracted from total resistance in MESFETs.

3.
Heliyon ; 9(10): e20416, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37822609

ABSTRACT

STEM education interrelates science, technology, engineering, and mathematics, ensuring that all interrelated contents are taught in coherence instead of in isolation. This promotes collaboration, critical thinking, and active engagement among students. The study ascertained the factors that compromise the implementation of STEM practices in the Bono East Region of Ghana to gain a moderately broad and deep understanding, allowing for a critical analysis of outcomes. It adopted a descriptive survey design to explore information concerning STEM education as it existed from May to October 2022. The study was carried out in Public Senior High and Vocational-Technical Schools in the Bono East Region of Ghana. The schools were split into STEM-related schools and non-STEM-related schools using a stratified sampling technique. Ten STEM-related schools were chosen using a purposive sampling method. 271 instructors from the departments of Science, Mathematics, and Information Communication Technology made up the study's population. A survey using a well-structured closed-ended questionnaire was administered online and the response obtained was transformed into frequencies and percentages in tabular forms using Microsoft Excel version 2016 (Microsoft, USA). Software Package for Social Sciences (SPSS) version 25 (IBM, USA) was used to perform a chi-square test to determine differences between responses obtained at the test significance of 5%. The study revealed that the general implementation of STEM practices throughout the studied Senior High Schools was below the mark. Inadequate STEM teaching-learning materials, limited certified STEM teachers, lack of STEM-dedicated infrastructure, inadequate professional development opportunities, absence of STEM documented standards and curriculum, limited access to technology, and limited time for teaching STEM-related subjects were some of the major factors contributing to the unsuccessful implementation of STEM practices in studied Public Senior High and Vocational-Technical Schools. Be that as it may, the study, therefore, recommended some measures including comprehensive STEM policies, adoptions of systematic STEM framework, and rigorous curriculum overhaul to be considered by the various stakeholders of education to realize the aspirations of inclusive STEM education.

4.
J Clin Med ; 12(13)2023 Jun 22.
Article in English | MEDLINE | ID: mdl-37445244

ABSTRACT

The base of the tongue (BOT) is the second most common site for squamous cell carcinoma (SCC) in the oropharynx. There are currently no clear guidelines for the management of BOT SCC. Our main objective was to compare the oncological outcomes of two minimally invasive approaches, transoral laser microsurgery (TLM) and transoral robot-assisted surgery (TORS). This was a retrospective French GETTEC (Groupe d'Études des Tumeurs de la Tête et du Cou) multicenter study of patients with BOT SCC removed surgically either by TLM or TORS between 2005 and 2021. The study group included 16 patients treated by TLM and 38 by TORS, with median follow-up times of 14.4 and 37.2 months, respectively. The overall survival (OS) rates at 2 and 3 years were 67% in the TLM group and 90% at 2 years and 86% at 3 years in the TORS group (p = 0.42, p = 0.20). There was no significant difference in recurrence-free survival (RFS) between the two techniques after 2 and 3 years. The tumors removed by TORS were significantly larger. Operative times were significantly shorter in the TLM group. There were no differences in feeding resumption; none of the patients in the TLM group required a tracheotomy. Postoperative hemorrhagic complication rates were similar in the two groups (12% for TLM and 13% for TORS). Both TORS and TLM showed encouraging oncological, functional, and safety results in BOT SCC even in recurrence or second primary cancer patients, without a technique being found superior in terms of OS or RFS. Tumors removed by TORS were larger without an increase in postoperative bleeding, extending the possibilities of transoral treatment.

5.
J Voice ; 2023 Mar 25.
Article in English | MEDLINE | ID: mdl-36973130

ABSTRACT

OBJECTIVES: This study presents an efficient, safe, effective, and novel technique of reconstructive transoral laser microsurgery (R-TLM) for the treatment of unilateral vocal fold paralysis (UVFP) with airway obstruction. It is based on the augmentation of the immobile and potentially flaccid and atrophic side while lateralizing the arytenoid and posterior part of the vocal fold, thus improving breathing without sacrificing phonation and commonly improving it. STUDY DESIGN: Retrospective cohort study through data from medical records and operative notes. METHODS: Patients with UVFP with exertional dyspnea with or without dysphonia were included in this report. The vocal fold is augmented by harvesting the aryepiglottic fold soft tissues and the upper part of the arytenoid and placing them into the paraglottic space as a pedicled microflap, thus augmenting the anterior two thirds of the vocal fold while lateralizing the remaining arytenoid and posterior third of the vocal fold by an internal traction suture to improve airway. Postoperative breathing, phonation and swallowing were assessed. RESULTS: Twenty two cases are reported in the study. Follow-up evaluations ranged from 6 to 12 months. All cases showed successful and durable improvement of breathing and phonation. None required tracheostomy or gastrostomy pre- or postoperatively. CONCLUSIONS: Augmentation-lateralization is a novel, safe, and effective minimally invasive technique that allows airway improvement with good results on phonation in patients with challenging UVFP with airway obstruction.

6.
Micromachines (Basel) ; 14(2)2023 Feb 12.
Article in English | MEDLINE | ID: mdl-36838139

ABSTRACT

We present a fully analytical model and physical investigation on the source resistance (RS) in InxGa1-xAs quantum-well high-electron mobility transistors based on a three-layer TLM system. The RS model in this work was derived by solving the coupled quadratic differential equations for each current component with appropriate boundary conditions, requiring only six physical and geometrical parameters, including ohmic contact resistivity (ρc), barrier tunneling resistivity (ρbarrier), sheet resistances of the cap and channel regions (Rsh_cap and Rsh_ch), side-recessed length (Lside) and gate-to-source length (Lgs). To extract each model parameter, we fabricated two different TLM structures, such as cap-TLM and recessed-TLM. The developed RS model in this work was in excellent agreement with the RS values measured from the two TLM devices and previously reported short-Lg HEMT devices. The findings in this work revealed that barrier tunneling resistivity already played a critical role in reducing the value of RS in state-of-the-art HEMTs. Unless the barrier tunneling resistivity is reduced considerably, innovative engineering on the ohmic contact characteristics and gate-to-source spacing would only marginally improve the device performance.

7.
Head Neck ; 45(4): 972-982, 2023 04.
Article in English | MEDLINE | ID: mdl-36825894

ABSTRACT

BACKGROUND: There are several options for primary surgical treatment of early-stage supraglottic squamous cell carcinoma (SCC), including transoral robotic surgery (TORS). The purpose of this study was to compare outcomes of TORS to open partial laryngectomy and transoral laser microsurgery (TLM). METHODS: Patients with clinical classification T1-2 supraglottic SCC diagnosed 2010-2019, treated with TORS, open partial laryngectomy, or TLM in the National Cancer Database were selected. RESULTS: One thousand six hundred three patients were included: 17% TORS, 26.5% TLM, 56.5% open. TORS patients had the lowest rates of adjuvant treatment (28.4% vs. TLM: 45.0%, open: 38.5%, p < 0.001), and lower positive margin rates than TLM (16.9% vs. 30.5%, p < 0.001). Thirty-day and ninety-day post-operative mortality did not differ between the approaches. Five-year survival was higher following TORS compared to open surgery (77.8% vs. 66.1%, p = 0.01); this difference persisted following matched-pair analysis. CONCLUSIONS: TORS may be a safe and effective surgical approach for early-stage supraglottic SCC in appropriate patients.


Subject(s)
Carcinoma, Squamous Cell , Head and Neck Neoplasms , Laryngeal Neoplasms , Larynx , Laser Therapy , Robotic Surgical Procedures , Humans , Laryngeal Neoplasms/pathology , Carcinoma, Squamous Cell/pathology , Treatment Outcome , Larynx/surgery , Squamous Cell Carcinoma of Head and Neck/surgery , Laryngectomy , Microsurgery , Head and Neck Neoplasms/surgery
8.
Ear Nose Throat J ; 102(6): NP294-NP297, 2023 Jun.
Article in English | MEDLINE | ID: mdl-33848206

ABSTRACT

Second primary cancer (SPC) is a term used to describe a new primary cancer occurring in patients who had formerly been diagnosed with tumor. Even though SPCs appear to be related to primary cancers, they are actually entities that have arisen independently and not as a result of recurrence. This report is of the first case in literature of a patient hospitalized for the surgical treatment of 3 synchronous Head and Neck Cancers. A 66-year-old male was admitted to our hospital (Ospedale Degli Infermi-Biella, Italy) complaining about pharyngodynia. Three different lesions were identified through endoscopic examination and narrow band imaging: the first one on left tonsil, the second one on epiglottis, and the third one on right aryepiglottic fold. The case was subject to a multidisciplinary team analysis due to its complexity, then the surgery consisted in (1) CO2 laser left tonsillectomy, associated with (2) CO2 laser excision of the lesion on epiglottis free edge, and (3) CO2 laser excision of right aryepiglottic fold lesion. Synchronous tumors are among the most defiant challenges for surgeons since no international guideline specifies differentiated strategies to be adopted in patients affected by synchronous Head and Neck Cancers, therefore surgical planning must be tailored differently from patient to patient, and many unsolved questions still concern clinical treatments to be adopted.


Subject(s)
Carbon Dioxide , Head and Neck Neoplasms , Male , Humans , Aged , Head and Neck Neoplasms/surgery , Endoscopy , Epiglottis/surgery , Italy
9.
Ann Otol Rhinol Laryngol ; 132(4): 361-370, 2023 Apr.
Article in English | MEDLINE | ID: mdl-35686520

ABSTRACT

OBJECTIVES: This study aims to demonstrate the benefit of reconstructive transoral laser microsurgery (R-TLM) in decannulation of tracheostomy-dependent patients with airway obstruction. METHODS: A consecutive series of tracheostomy-dependent patients who underwent R-TLM using multiple techniques described in our previous works, were reviewed for outcomes especially for decannulation. Full airway examination was essential to determine the anatomical and functional sites of obstruction to establish the surgical plan including R-TLM techniques needed to improve airway prior to permanent decannulation. RESULTS: Twenty-two patients were treated. Eighteen subjects were successfully decannulated. Single or multiple R-TLM surgical technique(s) was/were performed during the same surgery to treat upper airway stenosis at the level of the hypopharynx, larynx, and trachea. The mean number of surgeries per patient was 2.1. Patients were followed up for at least 12 months. CONCLUSION: R-TLM combines different surgical techniques which can be used individually or combined in a stepwise surgical plan for permanent decannulation of tracheostomy-dependent patients with a previous history of decannulation failure secondary to airway obstruction. Accurate preoperative examination gives valuable information about airway and allows establishing a stepwise surgical plan that may need multiple surgeries for full permanent decannulation of these patients.


Subject(s)
Airway Obstruction , Laser Therapy , Humans , Tracheostomy/methods , Microsurgery/methods , Retrospective Studies , Laser Therapy/methods , Airway Obstruction/surgery , Trachea/surgery , Lasers
10.
Auris Nasus Larynx ; 50(3): 415-422, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36163067

ABSTRACT

OBJECTIVE: Anterior commissure (AC) involvement is an unfavorable factor for transoral laser microsurgery (TLM) treatment of early glottic carcinoma (EGC). This study aimed to evaluate the therapeutic efficacy of TLM treatment for EGC with AC involvement. METHODS: From 2008 to 2017, 177 patients with T1-T2 EGC with AC involvement were retrospectively included and divided into the TLM group (n=115) receiving CO2 laser TLM and the control group undergoing open surgery (n=62). The survival outcomes, postoperative complications, laryngeal preservation rate, recurrence and the phonological results were compared between groups. RESULT: The TLM group had significantly reduced hospital stay, hospitalization costs, and intraoperative blood loss as compared with the control group. The tracheotomy rate was significantly higher in the control group (96.8% vs. 0%). The 5-year overall survival (OS) was 89.6% and 85.5% in the TLM group and control group, respectively. Log-rank test showed no difference in survival rate between the two groups. There was no significant difference in laryngeal preservation rate and overall recurrence rate between groups. In postoperative vocal function evaluation, there were significant differences in the overall grade (G), the roughness (R), the breathiness (B), Voice Handicap Index-10 (VHI-10), Jitter, Shimmer, noise/harmonic ratio (NHR), maximum phonation time (MPT), phonation threshold pressure (PTP) between the two groups. CONCLUSION: For EGC with AC involvement, TLM has similar survival outcomes with the open surgery, but has better postoperative voice outcomes. Meanwhile, TLM can effectively reduce intraoperative blood loss, hospitalization time, hospitalization costs and postoperative complications.


Subject(s)
Carcinoma , Laryngeal Neoplasms , Laser Therapy , Lasers, Gas , Humans , Microsurgery/methods , Carbon Dioxide , Treatment Outcome , Retrospective Studies , Blood Loss, Surgical , Glottis/surgery , Glottis/pathology , Laryngeal Neoplasms/pathology , Laser Therapy/methods , Lasers, Gas/therapeutic use , Carcinoma/pathology
11.
Front Genet ; 13: 1033113, 2022.
Article in English | MEDLINE | ID: mdl-36406126

ABSTRACT

The natural ends of the linear eukaryotic chromosomes are protected by telomeres, which also play an important role in aging and cancer development. Telomere length varies between species, but it is strictly controlled in all organisms. The process of Telomere Length Maintenance (TLM) involves many pathways, protein complexes and interactions that were first discovered in budding and fission yeast model organisms (Saccharomyces cerevisiae, Schizosaccharomyces pombe). In particular, large-scale systematic genetic screens in budding yeast uncovered a network of ≈ 500 genes that, when mutated, cause telomeres to lengthen or to shorten. In contrast, the TLM network in fission yeast remains largely unknown and systematic data is still lacking. In this work we try to close this gap and develop a unified interpretable machine learning framework for TLM gene discovery and phenotype prediction in both species. We demonstrate the utility of our framework in pinpointing the pathways by which TLM homeostasis is maintained and predicting novel TLM genes in fission yeast. The results of this study could be used for better understanding of telomere biology and serve as a step towards the adaptation of computational methods based on telomeric data for human prognosis.

12.
Ann Transl Med ; 10(14): 799, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35965819

ABSTRACT

Background: Although lymph node metastasis is a critical prognostic factor, the indications for neck dissection in recurrent glottic cancer after transoral laser microsurgery (TLM) are unclear. At present, there is no clear standard for simultaneous cervical lymph node dissection at home and abroad. Methods: We summarize the pattern of regional recurrence in glottic cancer after initial TLM and to evaluate the risk factors for neck metastasis. Seventy-five cases with recurrent glottic cancer after TLM between December 2004 and June 2014 were retrospectively analyzed. Survival, regional control rate, and neck metastasis were analyzed. The Kaplan-Meier method was used for survival analysis. Univariate analysis was performed with the log-rank test and multivariate analysis was completed using Cox regression. Results: The 5-year overall survival (OS), disease-specific survival (DSS), and regional control rate after the first TLM were 73.6%, 89.1%, and 69.7%, respectively. A total of 22 (29.3%) patients developed cervical metastases during long-term follow-up and showed a significant decline in OS and DSS rates. Multivariate analysis indicated that histological grading and type of TLM were both risk factors for neck metastasis. Patients treated with type Vc cordectomy were more likely to develop regional recurrence than patients treated with type III cordectomy [hazard ratio (HR) =14.737, 95% confidence interval (CI): 2.117-102.610, P=0.007]. No significant correlation was present between rT stage and neck metastasis. Conclusions: Multivariate analysis indicated that histological grading and type of TLM were both risk factors for neck metastasis. Patients with recurrence after type V cordectomy may have an increased risk of developing cervical lymph node metastasis, especially those with supraglottic spread or high-grade tumors.

13.
Biosensors (Basel) ; 12(2)2022 Jan 24.
Article in English | MEDLINE | ID: mdl-35200322

ABSTRACT

Love wave (L-SAW) sensors have been used to probe cell monolayers, but their application to detect changes beyond the focal adhesion points on cell monolayers, as viscosity changes on the cytoskeleton, has not been explored. In this work we present for the first time a Love wave sensor with tuned penetration depth and sensitivity to potentially detect mechanical changes beyond focal adhesion points of cell monolayers. We designed and fabricated a Love wave sensor operating at 30 MHz with sensitivity to detect viscous changes between 0.89 and 3.3 cP. The Love wave sensor was modeled using an acoustic transmission line model, whereas the response of interdigital transducers (IDTs) was modeled with the Campbell's cross-field circuit model. Our design uses a substrate with a high electromechanical coupling coefficient (LiNbO3 36Y-X), and an 8-µm polymeric guiding layer (SU-8). The design aims to overcome the high insertion losses of viscous liquid environments, and the loss of sensitivity due to the low frequency. The fabricated sensor was tested in a fluidic chamber glued directly to the SU-8 guiding layer. Our experiments with liquids of viscosity similar to those expected in cell monolayers showed a measurable sensor response. In addition, experimentation with SaOs-2 cells within a culture medium showed measurable responses. These results can be of interest for the development of novel cell-based biosensors, and novel characterization tools for cell monolayers.


Subject(s)
Acoustics , Biosensing Techniques , Biosensing Techniques/methods , Cell Adhesion/physiology , Transducers , Viscosity
14.
Otolaryngol Head Neck Surg ; 167(5): 839-845, 2022 11.
Article in English | MEDLINE | ID: mdl-35167384

ABSTRACT

OBJECTIVE: Transoral laser microsurgery and radiotherapy provide high and comparable cure rates for the treatment of early glottic cancer. However, the voice outcomes after treatment remain controversial. A modified type III cordectomy technique was proposed in 2006, and preliminary results showed it to be an oncologically safe method with satisfactory voice outcomes. This study aimed to evaluate oncologic and voice outcomes after long-term follow-up of these patients. STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary care academic center. METHODS: Between 2006 and 2018, 42 patients with glottic cancer underwent a modified type III cordectomy. This technique resected the tumor and upper part of the vocal folds and preserved the lower part of the vocalis muscle as a scaffold to improve glottis closure. The oncologic results and voice outcomes were evaluated at a median follow-up of 68 months. RESULTS: The primary tumor stages included 13 T1 (31%), 26 T2 (64%), and 3 T3 (7%). Eight patients (19%) had local recurrence, and 6 underwent successful salvage with transoral laser microsurgery with or without postoperative radiotherapy with laryngeal preservation. The 5-year rate of local control was 80%; laryngeal preservation, 95%; overall survival, 89%; and disease-specific survival, 97%. The final laryngeal preservation rate was 95% (40/42). The voice outcomes were satisfactory and comparable to those of patients who underwent type I and II cordectomies. CONCLUSION: The modified type III cordectomy has been proven to be an oncologically safe method with satisfactory voice outcomes after long-term follow-up in selected cases of early glottic cancer.


Subject(s)
Laryngeal Neoplasms , Laser Therapy , Tongue Neoplasms , Humans , Glottis/surgery , Laryngeal Neoplasms/surgery , Retrospective Studies , Voice Quality , Treatment Outcome , Tongue Neoplasms/pathology , Laser Therapy/methods , Microsurgery/methods
15.
Ann Biol Clin (Paris) ; 79(6): 535-549, 2021 12 01.
Article in French | MEDLINE | ID: mdl-34961737

ABSTRACT

During the first wave of Covid-19 in France, in spring 2020, healthcare institution's laboratory had to adapt itself quickly to the growing demand for emergency biology, in particular by reorganizing their POCT analyzers: redeployment of analyzers and/or new installations. In order to analyze this management, a subgroup of 15 hospital biologists from the SFBC Working Group "Biochemical markers of Covid-19" sent, in fall 2020, an on-line survey to French hospital laboratories using POCT. Answers analysis (n = 86) shows a territorial disparity related to the severity of the first wave: increased activity essentially in red zones, management of unexpected situations, training of additional nursing staff for 40 % of the laboratories... The survey also showed simplification of aspects related to accreditation those periods of health crisis. An additional survey, carried out in the spring of 2021, showed good overall satisfaction of the healthcare services (n = 139) concerning the services provided by biology in the POCT sector. Because of their great adaptation capacity, the laboratories and their POCT-teams have played a key role in the management of the first wave of Covid-19 in France. However, the success of these organizations requires an essential collaboration between laboratories and healthcare services. The results of this survey are fundamental in the context of the prolongation of the pandemia throughout the world with a POCT sector appearing to be growing.


Subject(s)
COVID-19 , Laboratories, Hospital , Accreditation , France , Humans , SARS-CoV-2
16.
Materials (Basel) ; 14(19)2021 Sep 26.
Article in English | MEDLINE | ID: mdl-34639986

ABSTRACT

This work presents a comparison of values of the contact resistivity of silicon solar cells obtained using the following methods: the transmission line model method (TLM) and the potential difference method (PD). Investigations were performed with two independent scientific units. The samples were manufactured with silver front electrodes. The co-firing process was performed in an infrared belt furnace in a temperature range of 840 to 960 °C. The electrical properties of a batch of solar cells fabricated in two cycles were investigated. This work focuses on the different metallisation temperatures of co-firing solar cells and measurements were carried out using the methods mentioned. In the TLM and PD methods, the same calculation formulae were used. Moreover, solar cell parameters measured with these methods had the same, similar, or sometimes different but strongly correlated values. Based on an analysis of the selected databases, this article diagnoses the recent and current state of knowledge regarding the employment of the TLM and PD methods and the available hardware base. These methods are of interest to various research centres, groups of specialists dealing with the optimisation of the electrical properties of silicon photovoltaic cells, and designers of measuring instruments.

18.
Sensors (Basel) ; 21(16)2021 Aug 04.
Article in English | MEDLINE | ID: mdl-34450719

ABSTRACT

Narrow band-gap semiconductors, namely ternary InAsSb alloys, find substantial technological importance for mid-infrared application as photodetectors in medical diagnostics or environmental monitoring. Thus, it is crucial to develop electrical contacts for these materials because they are the fundamental blocks of all semiconductor devices. This study demonstrates that electroplated gold contacts can be considered as a simple and reliable metallization technology for the electrical-response examination of a test structure. Unalloyed electroplated Au contacts to InAsSb exhibit specific contact resistivity even lower than vacuum-deposited standard Ti-Au. Moreover, temperature-dependent transport properties, such as Hall carrier concentration and mobility, show similar trends, with a minor shift in the transition temperature. It can be associated with a difference in metallization technology, mainly the presence of a Ti interlayer in vacuum-deposited contacts. Such a transition may give insight into not only the gentle balance changes between conductivity channels but also an impression of changing the dominance of carrier type from p- to n-type. The magnetotransport experiments assisted with mobility spectrum analysis clearly show that such an interpretation is incorrect. InAsSb layers are strongly p-type dominant, with a clear contribution from valence band carriers observed at the whole analyzed temperature range. Furthermore, the presence of thermally activated band electrons is detected at temperatures higher than 220 K.

19.
Laryngoscope ; 131(12): 2766-2772, 2021 12.
Article in English | MEDLINE | ID: mdl-34296772

ABSTRACT

OBJECTIVES: Transoral laser microsurgery (TLM) is commonly utilized for early glottic cancer and offers favorable oncologic and functional outcomes. However, the survival implications of salvage therapy for recurrent or persistent disease have not been definitively characterized. STUDY DESIGN: Retrospective, national database cohort study. METHODS: Data were extracted from Veterans Health Affairs (VHA) Informatics and Computing Infrastructure (VINCI) concerning the TLM-based management of T1-T2 glottic squamous cell carcinoma patients between 2000 and 2017. Patients were characterized as either requiring TLM-only, or in cases of persistent or recurrent local disease, TLM plus change in treatment modality (radiotherapy, chemoradiotherapy, or open surgery). Predictors of overall survival (OS), cancer-specific survival (CSS), and salvage-free survival were evaluated via Cox and Fine-Gray models. RESULTS: About 553 patients (70.9% T1a, 13.4% T1b, 15.7% T2) were included, with a median follow-up time of 74.5 months. The need for non-TLM salvage increased along with more advanced disease (11.7% T1a, 29.7% T1b, 32.2% T2). Compared to patients with T1a disease, those with T1b and T2 tumors initially treated with TLM had a significantly higher probability of receiving non-TLM salvage (T1b: HR 2.70, 95% CI: 1.61-4.54; T2: HR 3.02, 95% CI: 1.88-4.84). In a multivariable model, receipt of non-TLM salvage was not a significant predictor of either OS (HR = 0.91, 95% CI: 0.62-1.33, P = .624) or CSS (HR 1.21 95% CI 0.51-2.86, P = .667). CONCLUSION: The majority of patients with early glottic cancer that are managed with TLM do not require additional salvage therapy. When non-TLM salvage was required, there was no decrement in OS or CSS. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:2766-2772, 2021.


Subject(s)
Laryngeal Neoplasms/surgery , Natural Orifice Endoscopic Surgery/adverse effects , Neoplasm Recurrence, Local/therapy , Salvage Therapy/statistics & numerical data , Squamous Cell Carcinoma of Head and Neck/surgery , Aged , Aged, 80 and over , Chemoradiotherapy, Adjuvant/statistics & numerical data , Databases, Factual/statistics & numerical data , Female , Glottis/pathology , Humans , Laryngeal Neoplasms/diagnosis , Laryngeal Neoplasms/mortality , Male , Microsurgery/adverse effects , Microsurgery/methods , Middle Aged , Natural Orifice Endoscopic Surgery/methods , Neoplasm Recurrence, Local/epidemiology , Neoplasm Staging , Radiotherapy, Adjuvant/statistics & numerical data , Retrospective Studies , Salvage Therapy/methods , Squamous Cell Carcinoma of Head and Neck/diagnosis , Squamous Cell Carcinoma of Head and Neck/mortality , United States/epidemiology , United States Department of Veterans Affairs/statistics & numerical data
20.
Nano Lett ; 21(8): 3503-3510, 2021 Apr 28.
Article in English | MEDLINE | ID: mdl-33856222

ABSTRACT

Molybdenum disulfide (MoS2) has been regarded as one of the most important n-type two-dimensional (2D) transition metal dichalcogenide semiconductors for nanoscale electron devices. Relatively high contact resistance (RC) remains as an issue in the 2D-devices yet to be resolved. Reliable technique is very compelling to practically produce low RC values in device electronics, although scientific approaches have been made to obtain a record-low RC. To resolve this practical issue, we here use thermal-evaporated ultrathin LiF between channel and source/drain metal to fabricate 2D-like MoS2 field effect transistors (FETs) with minimum RC. Under 4-bar FET method, RC less than ∼600 Ω·µm is achieved from the LiF/Au contact MoS2 FET. Our normal 2-bar FET with LiF thus shows the same mobility as that of 4-bar FET that should have no RC in principle. On the basis of these results, ultrathin LiF is also applied for transparent conducting oxide contact, successfully enabling transparent MoS2 FETs.

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