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1.
Breast J ; 27(2): 165-169, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33482684

RESUMO

We compared the clinicopathologic characteristics and prognosis of adenosquamous carcinoma (ASQ) of the breast with invasive ductal carcinoma (IDC), utilizing the National Cancer Database (NCDB) from 2004 to 2015. 1 932 688 female patients had invasive breast carcinoma; 1 421 250 had IDC (73.5%); and 453 had ASQ (0.0002%). When compared to IDC, ASQ patients were significantly (P < .05) older and had grade 1 tumors; negative lymph nodes; ER/PR/HER2-negative tumors; and worse 5-year overall survival (64.9% vs 74%, respectively). Our study, largest to date on ASQ, revealed an aggressive carcinoma with a significantly worse prognosis than IDC. "Personalized medicine" treatment approach for patients with this uncommon carcinoma is needed.


Assuntos
Neoplasias da Mama , Carcinoma Adenoescamoso , Carcinoma Ductal de Mama , Mama , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/terapia , Carcinoma Adenoescamoso/diagnóstico , Feminino , Humanos , Prognóstico
2.
Nano Lett ; 20(6): 4437-4444, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32368920

RESUMO

Structuring materials with atomic precision is the ultimate goal of nanotechnology and is becoming increasingly relevant as an enabling technology for quantum electronics/spintronics and quantum photonics. Here, we create atomic defects in monolayer MoS2 by helium ion (He-ion) beam lithography with a spatial fidelity approaching the single-atom limit in all three dimensions. Using low-temperature scanning tunneling microscopy (STM), we confirm the formation of individual point defects in MoS2 upon He-ion bombardment and show that defects are generated within 9 nm of the incident helium ions. Atom-specific sputtering yields are determined by analyzing the type and occurrence of defects observed in high-resolution STM images and compared with Monte Carlo simulations. Both theory and experiment indicate that the He-ion bombardment predominantly generates sulfur vacancies.

3.
J Pediatr Psychol ; 40(9): 992-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25678533

RESUMO

OBJECTIVE: To examine the feasibility and format of the Promoting Resilience in Stress Management (PRISM) intervention among two groups of adolescents and young adults (AYAs) at-risk for poor outcomes: those with Type 1 diabetes (T1D) or cancer. METHODS: PRISM consists of two long or four short skills-based modules. English-speaking patients 12-25 years old were eligible if they had T1D for >6 months or cancer for >2 weeks. Feasibility was defined as an 80% completion rate and high satisfaction. Ongoing monitoring shaped iterative refinement of disease-specific approach. RESULTS: 12 of 15 patients with T1D (80%) completed the two-session intervention. 3 of 15 patients with cancer declined to complete the two-session version, citing prohibitive length of individual sessions. 12 (80%) completed the four-session version. Patient-reported satisfaction was high across groups. CONCLUSIONS: The PRISM intervention is feasible and well-accepted by AYAs with cancer or T1D. Differences in patient populations warrant differences in approach.


Assuntos
Aconselhamento , Diabetes Mellitus Tipo 1/psicologia , Neoplasias/psicologia , Satisfação Pessoal , Resiliência Psicológica , Estresse Psicológico/psicologia , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Projetos Piloto , Estresse Psicológico/terapia , Adulto Jovem
4.
Qual Health Res ; 25(10): 1372-82, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25904674

RESUMO

Photovoice is a research method developed to help communities share images as a tool for discussion of key issues. Although this may be useful to promote healthy behavior, using Photovoice in adolescents has been logistically challenging. Given adolescents' engagement in social media, our study explored the feasibility of using a photo-sharing mobile phone application, Instagram, to accomplish the principles of Photovoice. Twenty adolescents 14 to 18 years old with type 1 diabetes were asked to use Instagram to post any diabetes-related photo for 3 weeks. Individual interviews and a focus group were also offered, and recruitment and retention statistics were tracked. Of those approached (n = 47), 43% agreed to participate. Twelve were actively engaged. Shared photos were most likely to fall into the categories of diabetes care, humor, or food. Engaged participants universally reported the project to be a positive experience; however, there were technological and personal factors to consider for widespread implementation.


Assuntos
Diabetes Mellitus Tipo 1/psicologia , Fotografação/métodos , Projetos de Pesquisa , Rede Social , Adolescente , Comunicação , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino
5.
Nat Commun ; 12(1): 7287, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34911952

RESUMO

Atomic spin centers in 2D materials are a highly anticipated building block for quantum technologies. Here, we demonstrate the creation of an effective spin-1/2 system via the atomically controlled generation of magnetic carbon radical ions (CRIs) in synthetic two-dimensional transition metal dichalcogenides. Hydrogenated carbon impurities located at chalcogen sites introduced by chemical doping are activated with atomic precision by hydrogen depassivation using a scanning probe tip. In its anionic state, the carbon impurity is computed to have a magnetic moment of 1 µB resulting from an unpaired electron populating a spin-polarized in-gap orbital. We show that the CRI defect states couple to a small number of local vibrational modes. The vibronic coupling strength critically depends on the spin state and differs for monolayer and bilayer WS2. The carbon radical ion is a surface-bound atomic defect that can be selectively introduced, features a well-understood vibronic spectrum, and is charge state controlled.

6.
Nat Commun ; 12(1): 3822, 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34158488

RESUMO

For two-dimensional (2D) layered semiconductors, control over atomic defects and understanding of their electronic and optical functionality represent major challenges towards developing a mature semiconductor technology using such materials. Here, we correlate generation, optical spectroscopy, atomic resolution imaging, and ab initio theory of chalcogen vacancies in monolayer MoS2. Chalcogen vacancies are selectively generated by in-vacuo annealing, but also focused ion beam exposure. The defect generation rate, atomic imaging and the optical signatures support this claim. We discriminate the narrow linewidth photoluminescence signatures of vacancies, resulting predominantly from localized defect orbitals, from broad luminescence features in the same spectral range, resulting from adsorbates. Vacancies can be patterned with a precision below 10 nm by ion beams, show single photon emission, and open the possibility for advanced defect engineering of 2D semiconductors at the ultimate scale.

7.
BMJ Case Rep ; 13(1)2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31969412

RESUMO

Follicular lymphoma is the second most common subtype of non-Hodgkin's lymphoma affecting adults. Clinically, follicular lymphoma is generally indolent, most often presenting as a painless peripheral lymphadenopathy; however, a leucocytosis at presentation is exceedingly rare. We present the case of a 63-year-old woman with follicular lymphoma with a presenting hyperleucocytosis at diagnosis of 1 327 000/µL demonstrated on laboratory analysis work while hospitalised for progressive weakness. fluorescence in situ hybridization (FISH) panel was consistent with follicular lymphoma, which was positive for B-cell leukaemia/lymphoma 2 and negative for MYC Proto-Oncogene. Cytoreduction with rituximab-containing therapy was initiated, with the patient ultimately expiring. A leukaemic phase at presentation appears to be associated with poor outcome. The findings from our case, in addition to others, have potential implications in regard to prognostic utility. The current prognostic tool used to estimate overall survival for follicular lymphoma, Follicular Lymphoma International Prognostic Index, does not take leucocytosis into account.


Assuntos
Leucocitose/tratamento farmacológico , Leucocitose/etiologia , Linfoma Folicular/complicações , Linfoma Folicular/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica , Evolução Fatal , Feminino , Humanos , Pessoa de Meia-Idade , Proto-Oncogene Mas
8.
Sci Adv ; 6(38)2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32938664

RESUMO

Quantum dot-like single-photon sources in transition metal dichalcogenides (TMDs) exhibit appealing quantum optical properties but lack a well-defined atomic structure and are subject to large spectral variability. Here, we demonstrate electrically stimulated photon emission from individual atomic defects in monolayer WS2 and directly correlate the emission with the local atomic and electronic structure. Radiative transitions are locally excited by sequential inelastic electron tunneling from a metallic tip into selected discrete defect states in the WS2 bandgap. Coupling to the optical far field is mediated by tip plasmons, which transduce the excess energy into a single photon. The applied tip-sample voltage determines the transition energy. Atomically resolved emission maps of individual point defects closely resemble electronic defect orbitals, the final states of the optical transitions. Inelastic charge carrier injection into localized defect states of two-dimensional materials provides a powerful platform for electrically driven, broadly tunable, atomic-scale single-photon sources.

9.
Adv Mater ; 32(50): e2005159, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33169451

RESUMO

Reliable, controlled doping of 2D transition metal dichalcogenides will enable the realization of next-generation electronic, logic-memory, and magnetic devices based on these materials. However, to date, accurate control over dopant concentration and scalability of the process remains a challenge. Here, a systematic study of scalable in situ doping of fully coalesced 2D WSe2 films with Re atoms via metal-organic chemical vapor deposition is reported. Dopant concentrations are uniformly distributed over the substrate surface, with precisely controlled concentrations down to <0.001% Re achieved by tuning the precursor partial pressure. Moreover, the impact of doping on morphological, chemical, optical, and electronic properties of WSe2 is elucidated with detailed experimental and theoretical examinations, confirming that the substitutional doping of Re at the W site leads to n-type behavior of WSe2 . Transport characteristics of fabricated back-gated field-effect-transistors are directly correlated to the dopant concentration, with degrading device performances for doping concentrations exceeding 1% of Re. The study demonstrates a viable approach to introducing true dopant-level impurities with high precision, which can be scaled up to batch production for applications beyond digital electronics.

10.
ACS Nano ; 13(9): 10520-10534, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31393700

RESUMO

Control of impurity concentrations in semiconducting materials is essential to device technology. Because of their intrinsic confinement, the properties of two-dimensional semiconductors such as transition metal dichalcogenides (TMDs) are more sensitive to defects than traditional bulk materials. The technological adoption of TMDs is dependent on the mitigation of deleterious defects and guided incorporation of functional foreign atoms. The first step toward impurity control is the identification of defects and assessment of their electronic properties. Here, we present a comprehensive study of point defects in monolayer tungsten disulfide (WS2) grown by chemical vapor deposition using scanning tunneling microscopy/spectroscopy, CO-tip noncontact atomic force microscopy, Kelvin probe force spectroscopy, density functional theory, and tight-binding calculations. We observe four different substitutional defects: chromium (CrW) and molybdenum (MoW) at a tungsten site, oxygen at sulfur sites in both top and bottom layers (OS top/bottom), and two negatively charged defects (CD type I and CD type II). Their electronic fingerprints unambiguously corroborate the defect assignment and reveal the presence or absence of in-gap defect states. CrW forms three deep unoccupied defect states, two of which arise from spin-orbit splitting. The formation of such localized trap states for CrW differs from the MoW case and can be explained by their different d shell energetics and local strain, which we directly measured. Utilizing a tight-binding model the electronic spectra of the isolectronic substitutions OS and CrW are mimicked in the limit of a zero hopping term and infinite on-site energy at a S and W site, respectively. The abundant CDs are negatively charged, which leads to a significant band bending around the defect and a local increase of the contact potential difference. In addition, CD-rich domains larger than 100 nm are observed, causing a work function increase of 1.1 V. While most defects are electronically isolated, we also observed hybrid states formed between CrW dimers. The important role of charge localization, spin-orbit coupling, and strain for the formation of deep defect states observed at substitutional defects in WS2 as reported here will guide future efforts of targeted defect engineering and doping of TMDs.

11.
ACS Nano ; 12(7): 6545-6553, 2018 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-29911862

RESUMO

Supramolecular chemistry protocols applied on surfaces offer compelling avenues for atomic-scale control over organic-inorganic interface structures. In this approach, adsorbate-surface interactions and two-dimensional confinement can lead to morphologies and properties that differ dramatically from those achieved via conventional synthetic approaches. Here, we describe the bottom-up, on-surface synthesis of one-dimensional coordination nanostructures based on an iron (Fe)-terpyridine (tpy) interaction borrowed from functional metal-organic complexes used in photovoltaic and catalytic applications. Thermally activated diffusion of sequentially deposited ligands and metal atoms and intraligand conformational changes lead to Fe-tpy coordination and formation of these nanochains. We used low-temperature scanning tunneling microscopy and density functional theory to elucidate the atomic-scale morphology of the system, suggesting a linear tri-Fe linkage between facing, coplanar tpy groups. Scanning tunneling spectroscopy reveals the highest occupied orbitals, with dominant contributions from states located at the Fe node, and ligand states that mostly contribute to the lowest unoccupied orbitals. This electronic structure yields potential for hosting photoinduced metal-to-ligand charge transfer in the visible/near-infrared. The formation of this unusual tpy/tri-Fe/tpy coordination motif has not been observed for wet chemistry synthetic methods and is mediated by the bottom-up on-surface approach used here, offering pathways to engineer the optoelectronic properties and reactivity of metal-organic nanostructures.

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