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1.
Adv Mater ; : e2001367, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33225543

RESUMO

White light-emitting diodes (WLEDs) are promising next-generation solid-state light sources. However, the commercialization route for WLED production suffers from challenges in terms of insufficient color-rendering index (CRI), color instability, and incorporation of rare-earth elements. Herein, a new two-component strategy is developed by assembling two broadband emissive materials with self-trapped excitons (STEs) for high CRI and stable WLEDs. The strategy addresses effectively the challenging issues facing current WLEDs. Based on first-principles thermodynamic calculations, copper-based ternary halides composites, CsCu2 I3 @Cs3 Cu2 I5 , are synthesized by a facile one-step solution approach. The composites exhibit an ideal white-light emission with a cold/warm white-light tuning and a robust stability against heat, ultraviolet light, and environmental oxygen/moisture. A series of cold/warm tunable WLEDs is demonstrated with a maximum luminance of 145 cd m-2 and an external quantum efficiency of 0.15%, and a record high CRI of 91.6 is achieved, which is the highest value for lead-free WLEDs. Importantly, the fabricated device demonstrates an excellent operation stability in a continuous current mode, exhibiting a long half-lifetime of 238.5 min. The results promise the use of the hybrids of STEs-derived broadband emissive materials for high-performance WLEDs.

2.
Oncol Rep ; 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33200222

RESUMO

The long noncoding RNA cancer susceptibility candidate 9 (CASC9) has been revealed to be an oncogenic gene in several types of cancer, and high CASC9 expression is related to tumorigenesis and cancer progression. However, the role of CASC9 in bladder cancer (BC), particularly during epithelial­mesenchymal transition (EMT), has not been characterized. RT­qPCR, EdU, CCK­8, wound scratch, Transwell and flow cytometric assays were performed to detect CASC9 expression, miR­758­3p expression and their functions in BC. RNA FISH was used to detect CASC9 subcellular localization. Luciferase reporter assay, RT­qPCR assay and western blotting were used to explore the relationship of CASC9, miR­758­3p and TGF­ß2. In the present study, it was revealed that CASC9 regulated EMT in BC. CASC9 expression was significantly upregulated in BC cell lines and specimens compared to that in adjacent normal bladder tissues. Upregulated CASC9 was associated with increased invasion ability and poor prognosis of BC. CASC9 knockdown inhibited BC cell proliferation, migration and invasion. Furthermore, a bioinformatics study and luciferase reporter assays revealed that CASC9 functioned as a ceRNA for miR­758­3p. CASC9 inhibited microRNA (miR)­758­3p activity and resulted in the de­suppression of its target transforming growth factor (TGF)­ß2. TGF­ß signaling driven by TGF­ß2 was crucial for CASC9 to promote EMT in BC. Collectively, these results indicated that CASC9 sponged miR­758­3p to regulate the expression of TGF­ß2, which activated the TGF­ß signaling pathway and promoted proliferation and EMT in BC.

3.
J Am Chem Soc ; 142(44): 18741-18745, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33085460

RESUMO

Typical organic photovoltaic materials show high Urbach energies (ca. 25-50 meV), which is considerably higher than those of their inorganic counterparts and limits further improvement in the device efficiency of organic solar cells (OSCs). In this study, we introduce a facile method of selenium substitution to reduce the Urbach energy of organic photovoltaic materials to 20.4 meV (Y6Se), which is the lowest value reported for high-performance organic photovoltaic materials and very close to those (ca. 15 meV) of typical inorganic/hybrid semiconductors, such as crystalline silicon, gallium nitride, and lead-halide perovskite. Next, OSCs based on Y6Se showed 17.7% efficiency, which is among the best results for OSCs and the record efficiency of as-cast single junction OSCs to date.

4.
Medicine (Baltimore) ; 99(41): e22680, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33031337

RESUMO

Multiple factors, including increasing incidence, poor knowledge of stroke and lack of effective, noninvasive and convenient stroke risk prediction tools, make it more difficult for precautions against stroke in China. Effective prediction models for stroke may assist to establish better risk awareness and management, healthier lifestyle, and lower stroke incidence for people.The China Health and Retirement Longitudinal Survey was the development cohort. Logistic regression was applied to model's development, in which the candidate variables with statistically significant coefficient were included in the prediction model. The area under receiver operating characteristic curve (AUC) and 10-times cross-validation were used for internal validation. Cutoff point of high-risk group was measured by Youden index. The China Health and Nutrition Survey was the validation cohort.The development cohort and the validation cohort included 16557 and 5065 participants, and the incidence density was 358.207/100,000 person-year and 350.701/100,000 person-year, respectively. The model for 2-year new-onset stroke risk prediction included age, hypertension, diabetes, heart disease, and smoking. The AUC and cross-validation AUC were 0.707 (95% confidence interval[CI]: 0.664, 0.750) and the 0.710 (95% CI: 0.650, 0.736). The sensitivity, specificity and accuracy of the cutoff point were 0.774, 0.545, and 0.319. The AUC and cross-validation AUC were 0.800 (95% CI: 0.744, 0.856) and 0.811(95% CI:0.714, 0.847), and the sensitivity, specificity and accuracy of cutoff point being 0.857,0.569, and 0.426 in external validation.A simple prediction tool using 5 noninvasive and easily accessible factors can assist in 2-year new-onset stroke risk prediction in Chinese people over 45 years old, which is believed to be applicable in identifying high-risk individuals and health management in China.


Assuntos
Modelos Estatísticos , Acidente Vascular Cerebral/epidemiologia , Idoso , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco
5.
Neural Plast ; 2020: 8859251, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32908488

RESUMO

Mindfulness training has gained popularity in the scientific field and has been proposed as an efficient way for emotional regulation. Mindfulness-based cognitive therapy (MBCT) is designed especially for depressive people in reducing risk of depression relapse and is recommended in national guidelines as a treatment choice for relapse prevention in recurrent depression. The aim of the current study was to investigate the effects of mindfulness training on depressive symptoms of international students and probe into the mediating role of mindfulness in stressful events and depression. In addition, we introduced a new kind of mindfulness training, the breathing exercise-based mindfulness training, which is based on the integration of Buddhism and Daoism. Self-report questionnaires assessing the coping style, abnormal depressive behavior, and stressful live events were completed in 260 international students in China (mean age = 21.4 years). The results showed that (1) many international students showed depression symptoms, (2) stressful life events play a completely mediating role in the initiation of depression and anxiety, and (3) mindfulness training for 8 weeks significantly reduced the depressive symptoms, and it was also related to a positive coping style. This study has certain theoretical significance in exploring the mechanism of the occurrence and development of depression among international students and provides useful tools for this special group of international students. In addition, the international students can also learn Chinese culture through the training. These findings indicate that mindfulness training and positive coping style are interrelated with treating depressive symptoms for international students.

6.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(6): 786-792, 2020 Jun 30.
Artigo em Chinês | MEDLINE | ID: mdl-32895193

RESUMO

OBJECTIVE: To test the performance of CHA2DS2-VASc score in predicting stroke recurrence in first-ever ischemic stroke survivors without atrial fibrillation (AF). METHODS: A total of 768 patients were included in this study, including 475 male (61.85%) and 293 female patients (38.15%) with a mean age of 61.52±12.59 years (17-90 years). The baseline information of the patients was collected by face-to-face questionnaire survey and electronic medical record review, and their follow-up information was collected by telephone follow-up once every 3 months. Chi-square test and Wilcoxon rank sum test were used to compare the baseline characteristics between the patients regularly followed up and those withdrawn from the study. The area under the ROC curve (AUC), sensitivity, specificity, positive likelihood ratio and other indicators of CHA2DS2-VASc score were determined, and C-index based on Cox proportional hazards model was used to evaluate the performance of CHA2DS2- VASc score in predicting the risk of stroke recurrence in patients at different time points during the follow-up. RESULTS: The 1-year, 3-year, and 5-year recurrence rate of stroke was 10.59%, 20.45%, and 29.46% in these patients, respectively. The AUC value, Optimal Operating Point (OOP) and the corresponding positive likelihood ratios (LR+) for predicting stroke recurrence were 0.558 (95%CI: 0.492-0.624), 4.5, and 1.256 at 1 year; 0.574 (95%CI: 0.517-0.630), 4.5, and 1.397 at 3 years; and 0.604 (95%CI: 0.548-0.661), 4.5, and 1.655 at 5 years, respectively. Sensitivity analysis of congestive heart failure showed that the predictive effect of CHA2DS2-VASc score was basically unchanged. CONCLUSIONS: CHA2DS2-VASc score can be used to predict the 3-year and 5-year risk of stroke recurrence in first-ever ischemic stroke survivors without AF. The score has a better prediction ability for long-term stroke recurrence, but the prediction value remains low, suggesting the need to further improve the score or establish a new score for predicting stroke recurrence.


Assuntos
Fibrilação Atrial , Isquemia Encefálica , Acidente Vascular Cerebral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Medição de Risco , Fatores de Risco , Sobreviventes , Adulto Jovem
7.
J Int Med Res ; 48(9): 300060520945141, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32924683

RESUMO

Artificial intelligence (AI)-aided decision support has developed rapidly to meet the needs for effective analysis of substantial data sets from electronic medical records and medical images generated daily, and computer-assisted intelligent drug design. In clinical practice, paediatricians make medical decisions after obtaining a large amount of information about symptoms, physical examinations, laboratory test indicators, special examinations and treatments. This information is used in combination with paediatricians' knowledge and experience to form the basis of clinical decisions. This diagnosis and therapeutic strategy development based on large amounts of information storage can be applied to both large clinical databases and data for individual patients. To date, AI applications have been of great value in intelligent diagnosis and treatment, intelligent image recognition, research and development of intelligent drugs and intelligent health management. This review aims to summarize recent advances in the research and clinical use of AI in paediatrics.

8.
Artigo em Inglês | MEDLINE | ID: mdl-32812275

RESUMO

One of the main challenges in targeted alpha therapy is assuring delivery of the α-particle dose to the targeted cells. Thus, it is critical to identify ligands for α-emitting radiometals that will form complexes that are very stable, both in vitro and in vivo. In this investigation, thorium-227 (t1/2 = 18.70 days) chelation of ligands containing hydroxypyridinonate (HOPO) or picolinic acid (pa) moieties and the stability of the resultant complexes were studied. Chelation reactions were followed by reversed-phased HPLC and gamma spectroscopy. Studies revealed that high 227 Th chelation yields could be obtained within 2.5 h or less with ligands containing four Me-3,2-HOPO moieties, 1 (83%) and 2 (65%), and also with ligands containing pa moieties, H4 octapa 3 (65%) and H4 py4pa 6 (87%). No reaction occurred with H4 neunpa-p-Bn-NO2 4, and the chelation reaction with another pa ligand H4 pypa 5 gave inconsistent yields with a very broad radio-HPLC peak. The ligands spermine-(Me-3,2-HOPO)4 1, H4 octapa 3, and H4 py4pa 6 had high stability (i.e., 87% of 227 Th still bound to the ligand) in phosphate-buffered saline at room temperature over a 6-day period. Preliminary studies with ligand 6 demonstrated efficient chelation of thorium-226 (t1/2 = 30.57 min) when heated to 80°C for 5 min.

9.
Ann Pharmacother ; : 1060028020950726, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32815400

RESUMO

OBJECTIVE: To describe telehealth interventions and determine their effect on medication adherence for patients with type 2 diabetes, hypertension, and/or dyslipidemia. DATA SOURCES: PubMed/MEDLINE, EMBASE, Cochrane, CINAHL Plus, PsycINFO, Academic Search Ultimate, International Pharmaceutical Abstracts, Scopus, Web of Science, WHO Global Index Medicus, association websites, and gray literature were searched from January 1, 1998, to December 31, 2019. STUDY SELECTION AND DATA EXTRACTION: Eligible studies reported eHealth, mobile health, and telehealth interventions for adult patients prescribed medications for chronic condition management (eg, type 2 diabetes, hypertension, and/or dyslipidemia). Studies were required to evaluate medication adherence outcomes (eg, medication possession ratio [MPR], proportion of days covered (PDC)]. Randomized controlled trials, cohort studies, and controlled before-and-after studies were included. Multiple reviewers independently extracted data and evaluated risk of bias. DATA SYNTHESIS: Of 8693 studies identified, 13 reported either an MPR or PDC and were included in the systematic review. The systematic review demonstrated that electronic health (eHealth) and telehealth interventions were successful at improving medication adherence, whereas mobile health interventions did not improve medication adherence. RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE: This systematic review highlighted the available research and findings of studies assessing interventions to improve medication nonadherence among patients with type 2 diabetes, hypertension, and/or dyslipidemia. The evaluated findings lend support to the need for targeted medication adherence interventions based on patient population and practice settings. CONCLUSIONS: Telehealth modalities include telephonic outreach and specialized tools designed to increase health literacy. eHealth and telehealth medication adherence interventions were associated with improved MPR and/or PDC rates.

10.
Dalton Trans ; 49(24): 8051-8055, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32530004

RESUMO

A tetraphenylethene-based Pd2L4 metallacage was self-assembled from four TPE-pyridine ligands with two Pd2+ ions. This metallacage with D4 symmetry exhibited a classical aggregation-induced emission property in different solvents and reversible stimuli-responsive behaviour with chloride ions and silver ions, successively.

11.
Nucl Med Biol ; 2020 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-32409263

RESUMO

INTRODUCTION: The use of lysine-urea-glutamate (LuG) for targeting the PSMA antigen on prostate cancer (PCa) is a promising method for delivering the alpha particle-emitting radionuclide astatine-211 (211At) to metastatic PCa. High kidney localization has been a problem with radiolabeled LuG derivatives, but has been adequately addressed in radiometal-labeled DOTA-LuG derivatives by linker optimization. Herein, we report an investigation of an alternate approach to diminishing the kidney concentrations of radiolabeled LuG-containing compounds. METHODS: Our approach involves PEGylated LuG moieties and closo-decaborate (2-) moieties conjugated to streptavidin (SAv) or human serum albumin (HSA). After preparing the LuG conjugates, SAv and HSA conjugates were succinylated to decrease their kidney localization and radioiodinated for evaluation in athymic mice bearing C4-2B osseous PCa tumor xenografts. RESULTS: Covalently attaching LuG to succinylated SAv and HSA significantly reduced kidney localization, but unfortunately succinylation resulted in decreased tumor concentrations. In contrast, a potential metabolite [131I]16b, an unconjugated LuG derivative containing a dPEG4® linker, provided tumor concentrations of ~15% ID/g at 4 h pi. A second unconjugated LuG derivative with a similar structure, but containing a dPEG12® linker, [131I]16a had tumor concentrations of ~4%ID/g at 4 h pi. Those results suggest that long PEG linkers also affect tumor localization in a negative manner. CONCLUSION: Conjugation of PEGylated LuG derivatives to proteins can be an effective approach to diminishing kidney localization of radiolabeled LuG reagents, but the protein, linker and the method of linkage need to be further studied. Additionally, modification of the unconjugated 16b to decrease kidney localization may provide PCa targeting agents for use with radiohalogens, including 211At. Advances in knowledge and implications for patient care: This study is the first to evaluate PEGylated LuG and closo-decaborate (2-) moieties conjugated to proteins as potential methods for diminishing the kidney concentrations of radiolabeled LuG-containing compounds.

12.
Cell Rep ; 30(13): 4518-4527.e3, 2020 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-32234484

RESUMO

The small conductance mechanosensitive ion channel (MscS)-like (MSL) proteins in plants are evolutionarily conserved homologs of the bacterial small conductance mechanosensitive ion channels. As the sole member of the Arabidopsis MSL family localized in the mitochondrial inner membrane, MSL1 is essential to maintain the normal membrane potential of mitochondria. Here, we report a cryoelectron microscopy (cryo-EM) structure of Arabidopsis thaliana MSL1 (AtMSL1) at 3.3 Å. The overall architecture of AtMSL1 is similar to MscS. However, the transmembrane domain of AtMSL1 is larger. Structural differences are observed in both the transmembrane and the matrix domain of AtMSL1. The carboxyl-terminus of AtMSL1 is more flexible and the ß-barrel structure observed in MscS is absent. The side portals in AtMSL1 are significantly smaller, and enlarging the size of the portal by mutagenesis can increase the channel conductance. Our study provides a framework for eukaryotic MscS-like mechanosensitive ion channels and the gating mechanism of the MscS family.

13.
ACS Appl Mater Interfaces ; 12(20): 22630-22639, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32330383

RESUMO

Supramolecular coordination is an efficient strategy to construct supramolecular coordination frameworks with predesigned structures, assembled shapes, and specific function. In this work, we report the synthesis, structural characterization, and photophysical property of two tetraphenylethene-based supramolecular coordination frameworks 1a and 1b formed from 1,1,2,2-tetrakis(4-(pyridin-4-yl)phenyl)ethene (2a) or 1,1,2,2-tetrakis(4-((E)-2-(pyridin-4-yl)vinyl)phenyl)ethene (2b) and a linear difunctional platinum(II) ligand (3a) via coordination-driven self-assembly. Controlled by the specific angularity and geometry of tetraphenylethene (with 60° and 120°) and difunctional Pt(II) linker (with 180°), these supramolecular coordination frameworks possess a well-defined and two-dimensional (2D) rhombic network-type topology with good periodicity and porosity. Given the aggregation-induced emission (AIE) property of tetraphenylethene units and the porosity of frameworks, 1a and 1b have been successfully used as fluorescent platforms and energy donors to fabricate efficient artificial light-harvesting materials with two fluorescent acceptors (Nile Red and Sulforhodamine 101) via noncovalent interactions in aqueous solution. Furthermore, these light-harvesting materials have been applied for promoting cancer cell imaging with a full shift of imaging channels from blue/green channels to the red channel. Thus, this study provides an effective approach to fabricate functional frameworks as fluorescent platforms for developing more fluorescent materials.

14.
Inorg Chem ; 59(9): 6137-6146, 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32302134

RESUMO

Increasing access to the short-lived α-emitting radionuclide astatine-211 (211At) has the potential to advance targeted α-therapeutic treatment of disease and to solve challenges facing the medical community. For example, there are numerous technical needs associated with advancing the use of 211At in targeted α-therapy, e.g., improving 211At chelates, developing more effective 211At targeting, and characterizing in vivo 211At behavior. There is an insufficient understanding of astatine chemistry to support these efforts. The chemistry of astatine is one of the least developed of all elements on the periodic table, owing to its limited supply and short half-life. Increasing access to 211At could help address these issues and advance understanding of 211At chemistry in general. We contribute here an extraction chromatographic processing method that simplifies 211At production in terms of purification. It utilizes the commercially available Pre-Filter resin to rapidly (<1.5 h) isolate 211At from irradiated bismuth targets (Bi decontamination factors ≥876 000), in reasonable yield (68-55%) and in a form that is compatible for subsequent in vivo study. We are excited about the potential of this procedure to address 211At supply and processing/purification problems.

15.
Inorg Chem ; 59(8): 5713-5720, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32271009

RESUMO

Tunable luminescent materials have attracted considerable interest for their wide applications in electronic optical devices, biological probes and sensors, tunable displays, and security technologies. Herein, we describe a strategy of coordination-driven self-assembly in order to prepare discrete tetraphenylethene-based platinum(II) bis-triangular dicycles 1 and 2 with aggregation-induced emission properties. The X-ray structure confirms that they possess two triangular cavities in which free rotation of the central TPE unit is restricted. As a kind of fluorescent material, the AIE-active dicycles have good emissions with wide tunability based on their aggregate states by changing different solvents, adjusting the temperature, or combining them with other dyes (e.g., perylene) via a co-assembly process.

16.
J Nanosci Nanotechnol ; 20(8): 4824-4831, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32126661

RESUMO

Cold mix asphalt mixture has a low strength and poor water stability, hence to solve this challenge, a cold mix asphaltic liquid was prepared in this study based on microscopic properties. LB-10 gradation was adopted and basalt fiber was selected as a reinforcing agent. The optimum asphaltaggregate ratio was determined by the Marshall test, and mix proportion was also designed. The laboratory tests were used to systematically evaluate road performance of the cold mix asphalt mixture. From the test results, it was shown that the initial strength, molding strength, immersion Marshall strength, residual stability, freeze-thaw splitting ratio, residual rate and dynamic stability of self-made cold mix asphalt mixture were 2.42 kN, 4.87 kN, 6.79 kN, 92.8%, 82.05%, 99.5% and 632 times/mm respectively. The initial strength, molding strength and residual stability of mixture became 90.9%, 88.7%, and 96.2%, respectively of their former values after one-month storage, showing good workability. By analyzing its research data and comparing with its existing products, the developed cold mix asphalt mixture can not only meet the requirements for road performances of the cold mix asphalt mixture in terms of strength, workability and high temperature stability, but greatly improves the water stability, storage stability and cohesive performance of the mixture.

17.
Chem Commun (Camb) ; 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32068210

RESUMO

Two tetraphenylethene-based tetracationic dicyclophanes 1 and 2 were synthesized via a one-step SN2 reaction. Based on the central TPE unit and the slight difference of the outer linkers, 1 and 2 exhibited a classic aggregation-induced emission but contrasting mechanochromic luminescence under grinding, vaporing, or hydrostatic pressure in the solid state, and photochemical reactions with various emitting colours induced by photoirradiation in the solution state.

19.
Ann Behav Med ; 54(7): 510-517, 2020 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31926014

RESUMO

BACKGROUND: Obesity is a cardiovascular disease risk factor and affects approximately 13.7 million U.S. children and adolescents between the ages 2 and 19 years old in 2015-2016. PURPOSE: To determine the relationship between children's average long-term exposure to maternal depressive symptoms age 1 month to Grade 6 and adolescents' body mass index (BMI) z-score at age 15 mediated by the adolescents' depressive symptom experience. METHODS: A total of 1,364 infants and their families from the Eunice Kennedy Shriver National Institute of Child Health and Human Development Study of Early Child Care and Youth Development were recruited. RESULTS: Mediation analyses revealed a significant relationship between children's average long-term exposure to maternal depressive symptoms from age 1 month to Grade 6 and adolescents' BMI z-score at age 15 (total effect = 0.015, p = .013, 95% confidence interval (CI): 0.0032, 0.027). The adolescents' experience of depressive symptoms significantly mediated this relationship (indirect effect = 0.0021, bias-corrected bootstrapped 95% CI: 0.0004, 0.0044), with this mediated relationship more pronounced in girls. CONCLUSIONS: Findings indicate the possible existence of a mediating role of adolescents' depressive symptoms experience in the pathway from average long-term exposure to maternal depressive symptoms during children's early life to adolescents' elevated BMI.

20.
Phys Chem Chem Phys ; 22(4): 2122-2129, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31907508

RESUMO

The two-dimensional (2D) atomically thin layered materials have attracted significant attention for constructing next-generation integrated electronic and optoelectronic devices. A special class of 2D materials composed of quasi one-dimensional (1D) atomic chains that show intriguing properties are less studied. Here, two Se-containing 2D layered materials α-Se and Sb2Se3 that have quasi-1D atomic chains are investigated via first-principles electronic structure calculations. Results shows that the electronic properties of n-monolayers (n-MLs) stacked α-Se and Sb2Se3 exhibit distinct layer-dependence electronic properties. The band gap of 2D α-Se remarkably decreases with increasing thickness, whereas the band gap of 2D Sb2Se3 show negligible change with thickness. The evolution of lattice phonon frequencies with thickness also show similar distinction. The underpinnings of the diverse electronic properties are attributed to the different electronic coupling among the layers of α-Se and Sb2Se3 that results in different van der Waals interactions among chains/layers. Our study demonstrates the rich diversity in the properties of 2D layered materials composed of lower-dimensional structural motifs.

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