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1.
Med. infant ; 30(4): 336-339, Diciembre 2023. ilus, tab
Article in Spanish | LILACS, UNISALUD, BINACIS | ID: biblio-1524212

ABSTRACT

La infección por Bartonella henselae (BH) adopta diversas formas de presentación clínica en pediatría. Según la bibliografía la forma de presentación más frecuente en pacientes inmunocompetentes es la linfadenopatía única asociada a fiebre. En el 85 % de los casos se compromete un solo ganglio siendo los axilares y los epitrocleares los más frecuentemente involucrados. Existen otras formas de presentación menos frecuentes que debemos tener en consideración, para poder realizar un diagnóstico precoz e indicar un tratamiento adecuado si así lo requiere. El diagnóstico requiere de la sospecha clínica del equipo de salud tratante, junto al antecedente epidemiológico, los hallazgos clínicos del examen físico y la realización de serologías que incluyan el dosaje de inmunoglobulina M y G. Los objetivos del presente trabajo fueron reconocer las manifestaciones clínicas típicas y atípicas de la EAG por Bartonella henselae, describir la epidemiología, características clínicas y evolución de esta enfermedad que se presentaron en nuestro hospital. Se estudiaron un total de 187 pacientes. La media de edad fue de 7.6 años (rango 1-14); siendo 53.5% de género masculino. Las formas de presentación más frecuentes en nuestro trabajo fueron la adenitis y la fiebre. La mayoría recibió diversos esquemas de tratamiento antibiótico, secundario al retraso en el diagnóstico. La tasa de hospitalización fue muy baja, remitió con tratamiento ambulatorio con antibióticos o sin ellos (AU)


Bartonella henselae infection has different clinical presentations in pediatrics. According to the literature, the most common form of presentation in immunocompetent patients is single lymphadenopathy associated with fever. In 85 % of the cases a single lymph node is involved, with the axillary and epitrochlear nodes being the most commonly involved. There are other, less frequent, forms of presentation that should be taken into consideration in order to make an early diagnosis and indicate appropriate treatment if required. Diagnosis relies on clinical suspicion by the treating healthcare team, together with the epidemiological history, clinical findings on physical examination, and serology including immunoglobulin M and G dosage. The objectives of this study were to identify both the typical and atypical clinical manifestations of Bartonella henselae cat scratch disease, to describe the epidemiology, clinical characteristics, and outcomes of cases presenting at our hospital. A total of 187 patients were studied. The mean age was 7.6 years (range 1-14); 53.5% were male. The most frequent forms of presentation in our study were adenitis and fever. Most of them received different antibiotic treatment regimens due to delayed diagnosis. The hospitalization rate was very low and the disease typically resolved with outpatient treatment, with or without antibiotics (AU)


Subject(s)
Humans , Infant , Child, Preschool , Child , Adolescent , Cats , Cat-Scratch Disease/diagnosis , Cat-Scratch Disease/drug therapy , Cat-Scratch Disease/epidemiology , Bartonella henselae/isolation & purification , Fever , Lymphadenopathy , Serologic Tests , Retrospective Studies , Anti-Bacterial Agents/therapeutic use
2.
Tech Coloproctol ; 27(12): 1227-1234, 2023 12.
Article in English | MEDLINE | ID: mdl-36973527

ABSTRACT

PURPOSE: In patients with chemotherapy, there is no consensus on the timing of ileostomy closure. Ileostomy reversal could improve the quality of life and minimise the long-term adverse events of delayed closure. In this study, we evaluated the impact of chemotherapy on ileostomy closure and searched for the predictive factors for complications. METHODS: We retrospectively analysed 212 patients with rectal cancer who underwent ileostomy closure surgery during and without chemotherapy and were consecutively enrolled between 2010 and 2016. As a result of the heterogeneity of the two groups, propensity score matching (PSM) was performed with a 1:1 PSM cohort. RESULTS: A total of 162 patients were included in the analysis. The overall stoma closure-related complications (12.4% vs. 11.1%, p = 1.00) and major complications (2.5% vs. 6.2%, p = 0.44) were not significantly different between the two groups. Multivariate analysis demonstrated that chronic kidney disease and bevacizumab use are risk factors for major complications. CONCLUSION: Patients with oral or intravenous chemotherapy can safely have ileostomy closure with an adequate time delay from chemotherapy. When patients use bevacizumab, major complications related to ileostomy closure should still be cautioned.


Subject(s)
Ileostomy , Rectal Neoplasms , Humans , Ileostomy/adverse effects , Retrospective Studies , Bevacizumab/therapeutic use , Propensity Score , Quality of Life , Postoperative Complications/etiology , Rectal Neoplasms/drug therapy , Rectal Neoplasms/surgery , Rectal Neoplasms/complications , Treatment Outcome
3.
ACS Nano ; 15(2): 3359-3364, 2021 Feb 23.
Article in English | MEDLINE | ID: mdl-33570920

ABSTRACT

A van der Waals bonded moiré bilayer formed by sequential growth of TiSe2 and TiTe2 monolayers exhibits emergent electronic structure as evidenced by angle-resolved photoemission band mapping. The two monolayers adopt the same lattice orientation but incommensurate lattice constants. Despite the lack of translational symmetry, sharp dispersive bands are observed. The dispersion relations appear distinct from those for the component monolayers alone. Theoretical calculations illustrate the formation of composite bands by coherent electronic coupling despite the weak interlayer bonding, which leads to band renormalization and energy shifts.

4.
Sci Rep ; 10(1): 21758, 2020 12 10.
Article in English | MEDLINE | ID: mdl-33303895

ABSTRACT

This study aimed to develop biodegradable calcium alginate microcarriers with uniform particle size and spherical integrity for sustained-release targeting transarterial chemoembolization. To determine related parameters including the ratio of cross-linking volume (sodium alginate: CaCl2), concentrations of sodium alginate and CaCl2 solutions, collection distance, flow rate, stirring speed, syringe needle diameter and hardening time to fabricate the microcarriers, the Taguchi method was applied. Using different conditions, a total of 18 groups were prepared. The average size of microspheres from different groups was estimated as ~ 2 mm (range 1.1 to 1.6 mm). Signal-to-noise ratio analysis showed the optimal spherical integrity (F1) achieved when the above parameters were designed as 0.1, 2.5 wt%, 6 wt%, 8 cm, 30 mL/h, 150 rpm, 0.25 mm and 2 h, respectively. The best (F1), middle (F2) and worst (F3) groups were used for further experiments. Fourier-transform infrared spectroscopy spectrum showed that F1, F2 and F3 conformations were distinct from original sodium alginate. Drug-loaded calcium alginate microcarriers demonstrated rougher surfaces compared to microspheres without drug under transmission electron microscopy. Compared to pH 7.4, swelling rates in PBS were decreased at pH 6.5. Encapsulation and loaded efficiencies of the Dox-loaded microcarriers were estimated as ~ 40.617% and ~ 3.517%. In vitro experiments indicated that the F1 Dox-loaded microcarriers provide a well sustained-release efficacy for about two weeks at 37 °C in PBS. Treatments of calcium alginate microcarriers without the Dox in two distinct hepatocellular carcinoma-derived cell lines, Huh-7 and Hep-3B, indicated that these microcarriers were non-toxic. The Dox-loaded microcarriers displayed sustained-release capacity and reduced cell viabilities to ~ 30% in both cell lines on Day 12.


Subject(s)
Alginates , Capsules , Chemoembolization, Therapeutic/methods , Doxorubicin/administration & dosage , Drug Carriers , Microspheres , Alginates/pharmacology , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/therapy , Cell Line, Tumor , Cell Survival/drug effects , Delayed-Action Preparations , Doxorubicin/pharmacology , Drug Carriers/pharmacology , Humans , Liver Neoplasms/pathology , Liver Neoplasms/therapy , Particle Size
5.
Phys Rev Lett ; 125(17): 176405, 2020 Oct 23.
Article in English | MEDLINE | ID: mdl-33156647

ABSTRACT

Single layers of transition metal dichalcogenides are of interest for emergent properties; an often-neglected issue is substrate effects. Our experiments show that the charge density wave in a single-layer TiTe_{2} grown on PtTe_{2} films is strongly suppressed by increasing the PtTe_{2} substrate thickness. Given that the interfacial bonding remains of the weak incommensurate van der Waals type, the observed changes are correlated with a thickness-dependent metallicity transformation in the PtTe_{2} substrate. The results illustrate the crucial role of the substrate in single-layer physics.

6.
Int J Tuberc Lung Dis ; 24(9): 922-927, 2020 09 01.
Article in English | MEDLINE | ID: mdl-33156759

ABSTRACT

BACKGROUND: Disseminated Mycobacterium avium complex infection (DMAC) has symptoms and microscopic findings similar to those of TB in HIV patients. To inform a clinical algorithm-based differential diagnosis, we aimed to characterise the clinical features of DMAC.METHODS: This was a retrospective cohort study of 192 HIV-positive patients with culture-confirmed mycobacterial infections hospitalised during 1996-2016 at a major HIV/AIDS treatment centre in Taiwan.RESULTS: HIV patients with DMAC (n = 58) had a three times higher 1-year mortality than those with TB (n = 98) (48.3% vs. 16.3%, P < 0.001). DMAC and TB were not distinguishable by the WHO TB screening criteria (fever, cough, night sweats or weight loss). Nevertheless, DMAC was characterised by a lower median CD4 count (5.0 cells/µL vs. 38.5 cells/µL, P < 0.001), lower median body mass index (BMI) (17.7 kg/m² vs. 19.7 kg/m², P = 0.002) and the absence of chest radiographic findings (P < 0.001). Simultaneous presence of CD4 <20 cells/µl, BMI <18.5 kg/m² and negative chest radiographic finding had a 98% specificity for diagnosing DMAC against TB or other types of mycobacterial infections.CONCLUSION: DMAC is an important differential diagnosis of TB in HIV patients. A simple rule based on CD4, BMI and chest radiography may inform the decision to start anti-DMAC treatment in patients with mycobacterial infection.


Subject(s)
HIV Infections , Mycobacterium avium-intracellulare Infection , Mycobacterium tuberculosis , Tuberculosis , Diagnosis, Differential , HIV Infections/complications , Humans , Mycobacterium avium Complex , Mycobacterium avium-intracellulare Infection/diagnosis , Retrospective Studies , Taiwan/epidemiology , Tuberculosis/diagnosis
7.
Phys Rev Lett ; 124(23): 236402, 2020 Jun 12.
Article in English | MEDLINE | ID: mdl-32603150

ABSTRACT

Interfacing bulk conducting topological Bi_{2}Se_{3} films with s-wave superconductors initiates strong superconducting order in the nontrivial surface states. However, bulk insulating topological (Bi_{1-x}Sb_{x})_{2}Te_{3} films on bulk Nb instead exhibit a giant attenuation of surface superconductivity, even for films only two layers thick. This massive suppression of proximity pairing is evidenced by ultrahigh-resolution band mappings and by contrasting quantified superconducting gaps with those of heavily n-doped topological Bi_{2}Se_{3}/Nb. The results underscore the limitations of using superconducting proximity effects to realize topological superconductivity in nearly intrinsic systems.

8.
Sci Adv ; 6(12): eaaz5015, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32219169

ABSTRACT

The emergence of quantization at the nanoscale, the quantum size effect (QSE), allows flexible control of matter and is a rich source of advanced functionalities. A QSE-induced transition into an insulating phase in semimetallic nanofilms was predicted for bismuth a half-century ago and has regained new interest with regard to its surface states exhibiting nontrivial electronic topology. Here, we reveal an unexpected mechanism of the transition by high-resolution angle-resolved photoelectron spectroscopy combined with theoretical calculations. Anomalous evolution and degeneracy of quantized energy levels indicate that increased Coulomb repulsion from the surface states deforms a quantum confinement potential with decreasing thickness. The potential deformation strongly modulates spatial distributions of quantized wave functions, which leads to acceleration of the transition beyond the original QSE picture. This discovery establishes a complete picture of the long-discussed transition and highlights a new class of size effects dominating nanoscale transport in systems with metallic surface states.

9.
Phys Rev Lett ; 124(3): 036402, 2020 Jan 24.
Article in English | MEDLINE | ID: mdl-32031832

ABSTRACT

Platinum ditelluride (PtTe_{2}), a type-II Dirac semimetal, remains semimetallic in ultrathin films down to just two triatomic layers (TLs) with a negative gap of -0.36 eV. Further reduction of the film thickness to a single TL induces a Lifshitz electronic transition to a semiconductor with a large positive gap of +0.79 eV. This transition is evidenced by experimental band structure mapping of films prepared by layer-resolved molecular beam epitaxy, and by comparing the data to first-principles calculations using a hybrid functional. The results demonstrate a novel electronic transition at the two-dimensional limit through film thickness control.

11.
Phys Rev Lett ; 121(19): 196402, 2018 Nov 09.
Article in English | MEDLINE | ID: mdl-30468619

ABSTRACT

Single layers of transition metal dichalcogenides (TMDCs) are excellent candidates for electronic applications beyond the graphene platform; many of them exhibit novel properties including charge density waves (CDWs) and magnetic ordering. CDWs in these single layers are generally a planar projection of the corresponding bulk CDWs because of the quasi-two-dimensional nature of TMDCs; a different CDW symmetry is unexpected. We report herein the successful creation of pristine single-layer VSe_{2}, which shows a (sqrt[7]×sqrt[3]) CDW in contrast to the (4×4) CDW for the layers in bulk VSe_{2}. Angle-resolved photoemission spectroscopy from the single layer shows a sizable (sqrt[7]×sqrt[3]) CDW gap of ∼100 meV at the zone boundary, a 220 K CDW transition temperature twice the bulk value, and no ferromagnetic exchange splitting as predicted by theory. This robust CDW with an exotic broken symmetry as the ground state is explained via a first-principles analysis. The results illustrate a unique CDW phenomenon in the two-dimensional limit.

12.
Transplant Proc ; 50(9): 2738-2741, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30401387

ABSTRACT

BACKGROUND: Ensuring careful selection of heart transplant recipients with pretransplant malignancies (PTM) has been suggested in several retrospective studies. However, cancer survival rates continue to increase and we still lack outcomes data on PTM patients who have undergone heart transplantation (HT) within the Asian region. Herein we report pretransplant characteristics and outcomes among PTM patients with HT. METHODS: A total of 354 patients underwent HT from January 2004 to January 2016. Eight of these patients had a history malignancy that was being treated before transplantation. Posttransplant outcomes and clinical characteristics were collected and possible prognostic factors analyzed. RESULTS: The median age of the patients with a preexisting malignancy was 60 years. The PTM group included 5 males and 3 females, with a median duration of follow-up of 43 months. In this group there were 2 patients with lymphoma after chemotherapy, 1 with colon cancer postoperatively, and 1 was on chemotherapy. In the other 4 patients, nasopharyngeal cancer, thyroid cancer, breast cancer, and endometrial cancer were identified, and each had undergone treatment. Only 1 premalignancy patient, with nasopharyngeal cancer, had disease recurrence. The 5-year overall survival of these patients was 50.0 ± 17.7%, but 5-year survival for those without PTM was 68.7 ± 2.0%. CONCLUSION: PTM was 2.3% in our cohort. PTM is associated with an increased risk of all-cause mortality. Thus, our findings suggest careful consideration when selecting PTM patients for HT.


Subject(s)
Heart Transplantation/mortality , Neoplasms/complications , Neoplasms/mortality , Adult , Aged , Child , Cohort Studies , Comorbidity , Female , Humans , Male , Middle Aged , Retrospective Studies , Risk Factors , Survival Rate
13.
Transplant Proc ; 50(9): 2756-2758, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30401391

ABSTRACT

Everolimus (EVR) can be used with calcineurin inhibitors to reduce the risk of renal dysfunction, with similar immunosuppressive effect. In this study, we compared renal function after heart transplantation (HT) under EVR with cyclosporine (CSA) or tacrolimus (TAC). Between 2004 and 2014, EVR with CSA or TAC was used in 117 HT at the National Taiwan University Hospital. After HT, all patients received corticosteroid, EVR (C0 target 3-8 ng/mL) and CSA (C0 blood level 100-200 ng/mL), or TAC (Co blood level 5-10 ng/mL). Renal function was evaluated before HT, every month after HT for up to 1 year, and then every 3 months for up to 2 years. Blood-drug levels of EVR, CSA, and TAC were also monitored simultaneously with renal function. The estimated mean glomerular filtration rate (eGFR) was 76.5 mL/min/1.73 m2 before HT. After HT, the eGFR was 64 mL/min/1.73 m2 at the third month, and 64 mL/min/1.73 m2 at the end of first year. The difference was significant between pre-HT and post-HT (P = .00) during the first year. No significant differences were noted between the CSA and TAC groups. Careful monitoring of blood-drug level and renal function is crucial after heart transplantation. It is concluded that under close monitoring blood-drug level and renal function, it is possible to reach acceptable postoperative renal function with no difference of renal function between EVR plus CSA and EVR plus TAC.


Subject(s)
Cyclosporine/adverse effects , Everolimus/adverse effects , Heart Transplantation/methods , Immunosuppressive Agents/adverse effects , Renal Insufficiency/chemically induced , Tacrolimus/adverse effects , Adult , Calcineurin Inhibitors/adverse effects , Drug Therapy, Combination , Female , Glomerular Filtration Rate/drug effects , Humans , Male , Middle Aged , Renal Insufficiency/epidemiology , Taiwan
14.
Hong Kong Med J ; 24(4): 378-383, 2018 08.
Article in English | MEDLINE | ID: mdl-30065125

ABSTRACT

INTRODUCTION: In Hong Kong, persons in custody receive primary medical care within the institutions of the Correctional Services Department (CSD). However, for psychiatric care, persons in custody must attend specialist out-patient clinics (SOPCs), which may cause embarrassment and stigmatisation. The aim of this interventional pilot study was to compare teleconsultations with face-to-face consultations for a group of stable Chinese psychiatric out-patients in custody. METHODS: A total of 86 stable Chinese male out-patients in custody were recruited for psychiatric teleconsultations. They were compared with 249 age-matched Chinese male out-patients in custody attending standard face-to-face psychiatric consultations at other SOPCs. The two groups had comparable baseline characteristics including age, education level, and 12-item Chinese General Health Questionnaire (C-GHQ-12) score. A satisfaction survey of patients towards the teleconsultation was also carried out. RESULTS: Compared with the face-to-face consultation group, the teleconsultation group showed a significantly better result in the difference in C-GHQ-12 scores before and after consultations (P=0.023). The correlation between the first and second teleconsultations also showed a moderate positive relationship (r=0.309). The satisfaction survey showed a favourable response to teleconsultations. No significant adverse events were identified for the teleconsultation group. CONCLUSIONS: The results suggest that teleconsultations are a sustainable and safe alternative to face-to-face consultations for stable Chinese psychiatric out-patients in custody.


Subject(s)
Mental Disorders/therapy , Outpatients/psychology , Prisoners/psychology , Remote Consultation/methods , Adult , Hong Kong , Humans , Male , Middle Aged , Pilot Projects , Surveys and Questionnaires
15.
Nat Commun ; 9(1): 2003, 2018 05 21.
Article in English | MEDLINE | ID: mdl-29784909

ABSTRACT

Two-dimensional (2D) topological insulators (TIs) are promising platforms for low-dissipation spintronic devices based on the quantum-spin-Hall (QSH) effect, but experimental realization of such systems with a large band gap suitable for room-temperature applications has proven difficult. Here, we report the successful growth on bilayer graphene of a quasi-freestanding WSe2 single layer with the 1T' structure that does not exist in the bulk form of WSe2. Using angle-resolved photoemission spectroscopy (ARPES) and scanning tunneling microscopy/spectroscopy (STM/STS), we observe a gap of 129 meV in the 1T' layer and an in-gap edge state located near the layer boundary. The system's 2D TI characters are confirmed by first-principles calculations. The observed gap diminishes with doping by Rb adsorption, ultimately leading to an insulator-semimetal transition. The discovery of this large-gap 2D TI with a tunable band gap opens up opportunities for developing advanced nanoscale systems and quantum devices.

16.
Nat Commun ; 8(1): 516, 2017 09 11.
Article in English | MEDLINE | ID: mdl-28894137

ABSTRACT

Two-dimensional materials constitute a promising platform for developing nanoscale devices and systems. Their physical properties can be very different from those of the corresponding three-dimensional materials because of extreme quantum confinement and dimensional reduction. Here we report a study of TiTe2 from the single-layer to the bulk limit. Using angle-resolved photoemission spectroscopy and scanning tunneling microscopy and spectroscopy, we observed the emergence of a (2 × 2) charge density wave order in single-layer TiTe2 with a transition temperature of 92 ± 3 K. Also observed was a pseudogap of about 28 meV at the Fermi level at 4.2 K. Surprisingly, no charge density wave transitions were observed in two-layer and multi-layer TiTe2, despite the quasi-two-dimensional nature of the material in the bulk. The unique charge density wave phenomenon in the single layer raises intriguing questions that challenge the prevailing thinking about the mechanisms of charge density wave formation.Due to reduced dimensionality, the properties of 2D materials are often different from their 3D counterparts. Here, the authors identify the emergence of a unique charge density wave (CDW) order in monolayer TiTe2 that challenges the current understanding of CDW formation.

17.
Nanotechnology ; 28(39): 395706, 2017 Sep 27.
Article in English | MEDLINE | ID: mdl-28745615

ABSTRACT

Two-dimensional topological insulators show great promise for spintronic applications. Much attention has been placed on single atomic or molecular layers, such as bismuthene. The selections of such materials are, however, limited. To broaden the base of candidate materials with desirable properties for applications, we report herein an exploration of the physics of double layers of bismuthene and antimonene. The electronic structure of a film depends on the number of layers, and it can be modified by epitaxial strain, by changing the effective spin-orbit coupling strength, and by the manner in which the layers are geometrically stacked. First-principles calculations for the double layers reveal a number of phases, including topological insulators, topological semimetals, Dirac semimetals, trivial semimetals, and trivial insulators. Their phase boundaries and the stability of the phases are investigated. The results illustrate a rich pattern of phases that can be realized by tuning lattice strain and effective spin-orbit coupling.

18.
Phys Rev Lett ; 118(16): 164802, 2017 Apr 21.
Article in English | MEDLINE | ID: mdl-28474903

ABSTRACT

The generation of intense electron beams with low emittance is key to both the production of coherent x rays from free electron lasers, and electron pulses with large transverse coherence length used in ultrafast electron diffraction. These beams are generated today by photoemission from disordered polycrystalline surfaces. We show that the use of single crystal surfaces with appropriate electronic structures allows us to effectively utilize the physics of photoemission to generate highly directed electron emission, thus reducing the emittance of the electron beam being generated.

19.
East Asian Arch Psychiatry ; 27(1): 3-10, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28387207

ABSTRACT

This study aimed to assess the psychometric properties of the Chinese version of the Revised Clinical Interview Schedule (C-CIS-R), and explore its applicability as a diagnostic instrument for common mental disorders (CMDs) in Hong Kong. Its psychometric properties were evaluated among 140 patients and 161 healthy controls. In comparison to the diagnoses made by the Structured Clinical Interview for the DSM-IV, the C-CIS-R showed good criterion validity in diagnosing CMDs. The correlation of the total score of C-CIS-R with the 12-item General Health Questionnaire and Hospital Anxiety and Depression Scale was satisfactory, indicating favourable convergent validity as well. The inter-rater and test-retest reliability were also satisfactory. Receiver operating characteristic analyses suggested an optimal cut-off point of 11/12 for detecting diagnosable CMDs (sensitivity: 0.69; specificity: 0.93) and 17/18 for identifying a need for treatment (sensitivity: 0.70; specificity: 0.95). In conclusion, C-CIS-R is a valid diagnostic instrument for CMDs in a Chinese community. Its cut-off points for clinically significant symptoms and treatment needs among Chinese are identical to those adopted in the original English version.


Subject(s)
Asian People/psychology , Mental Disorders/diagnosis , Psychiatric Status Rating Scales/standards , Adolescent , Adult , Aged , Case-Control Studies , Diagnostic and Statistical Manual of Mental Disorders , Female , Hong Kong , Humans , Male , Middle Aged , Psychometrics , Young Adult
20.
Phys Rev Lett ; 117(23): 236402, 2016 Dec 02.
Article in English | MEDLINE | ID: mdl-27982650

ABSTRACT

The topology of pure Bi is controversial because of its very small (∼10 meV) band gap. Here we perform high-resolution angle-resolved photoelectron spectroscopy measurements systematically on 14-202 bilayer Bi films. Using high-quality films, we succeed in observing quantized bulk bands with energy separations down to ∼10 meV. Detailed analyses on the phase shift of the confined wave functions precisely determine the surface and bulk electronic structures, which unambiguously show nontrivial topology. The present results not only prove the fundamental property of Bi but also introduce a capability of the quantum-confinement approach.

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