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Abstract Functional traits reveal the adaptive strategies of species to their environment, and are relevant to the formation of communities, the function of ecosystems, and the mechanisms underlying biodiversity. However, trait databases have not been established for most biological taxa, especially for insects, which encompass a vast number of species. This study measured the morphological traits of 307 species of Heteroptera insects collected in 2019 from the “Xishuangbanna Priority Conservation Area” in Southwest China using sweep netting and light trapping methods. This study provides a dataset for 307 Heteroptera species, comprising 34 morphometric measurements and 17 morphological traits. The dataset contains information on species sex, abundance, and the average, maximum, and minimum values of traits. This dataset facilitates an enhanced understanding of the functional traits and ecological associations of Heteroptera insects and offers opportunities for exploring a more diverse range of research topics.

Abstract Background The pentose phosphate pathway (PPP) is an important mechanism by which tumour cells resist stressful environments and maintain malignant proliferation. However, the mechanism by which the PPP regulates these processes in colorectal cancer (CRC) remains elusive. Methods Closely related PPP genes were obtained from the TCGA and GEO databases. The effect of ATP13A2 on CRC cell proliferation was evaluated by performing in vitro assays. The connection between the PPP and ATP13A2 was explored by assessing proliferation and antioxidative stress. The molecular mechanism by which ATP13A2 regulates the PPP was investigated using chromatin immunoprecipitation and dual luciferase experiments. The clinical therapeutic potential of ATP13A2 was explored using patient‐derived xenograft (PDX), patient‐derived organoid (PDO) and AOM/DSS models. Findings We identified ATP13A2 as a novel PPP‐related gene. ATP13A2 deficiency inhibited CRC growth and PPP activity, as manifested by a decrease in the levels of PPP products and an increase in reactive oxygen species levels, whereas ATP13A2 overexpression induced the opposite effect. Mechanistically, ATP13A2 regulated the PPP mainly by affecting phosphogluconate dehydrogenase (PGD) mRNA expression. Subsequent studies showed that ATP13A2 overexpression promoted TFEB nuclear localization by inhibiting the phosphorylation of TFEB, thereby enhancing the transcription of PGD and ultimately affecting the activity of the PPP. Finally, ATP13A2 knockdown inhibited CRC growth in PDO and PDX models. ATP13A2−/− mice had a lower CRC growth capacity than ATP13A2+/+ in the AOM/DSS model.Our findings revealed that ATP13A2 overexpression‐driven dephosphorylation of TFEB promotes PPP activation by increasing PGD transcription, suggesting that ATP13A2 may serve as a potential target for CRC therapy.

Abstract The RNA binding protein PTBP3 was recently reported to play a critical role in multiple cancers, and the molecular mechanisms involved RNA splicing, 3′ end processing and translation. However, the role of PTBP3 in colorectal cancer (CRC) remains poorly explored. Herein, PTBP3 was upregulated in CRC and associated with a poor prognosis. PTBP3 knockdown in colorectal cancer cell lines restricted CRC proliferative capacities in vitro and in vivo. Mechanistically, PTBP3 regulated the expression of the E3 ubiquitin ligase UBE4A by binding the 3′ UTR of its mRNA, preventing its degradation. UBE4A participated in P53 degradation, and PTBP3 knockdown in colorectal cancer cell lines showed increased P53 expression. UBE4A overexpression rescued PTBP3 knockdown-induced inhibition of CRC cell proliferation and P53 expression. Our results demonstrated that PTBP3 plays an essential role in CRC cell proliferation by stabilizing UBE4A to regulate P53 expression and may serve as a new prognostic biomarker and effective therapeutic target for CRC.

Abstract Colorectal cancer (CRC) is a common hereditary tumor that is often fatal. Its pathogenesis involves multiple genes, including circular RNAs (circRNAs). Notably, circRNAs constitute a new class of noncoding RNAs (ncRNAs) with a covalently closed loop structure and have been characterized as stable, conserved molecules that are abundantly expressed in tissue/development-specific patterns in eukaryotes. Based on accumulating evidence, circRNAs are aberrantly expressed in CRC tissues, cells, exosomes, and blood from patients with CRC. Moreover, numerous circRNAs have been identified as either oncogenes or tumor suppressors that mediate tumorigenesis, metastasis and chemoradiation resistance in CRC. Although the regulatory mechanisms of circRNA biogenesis and functions remain fairly elusive, interesting results have been obtained in studies investigating CRC. In particular, the expression of circRNAs in CRC is comprehensively modulated by multiple factors, such as splicing factors, transcription factors, specific enzymes and cis-acting elements. More importantly, circRNAs exert pivotal effects on CRC through various mechanisms, including acting as miRNA sponges or decoys, interacting with RNA binding proteins, and even translating functional peptides. Finally, circRNAs may serve as promising diagnostic and prognostic biomarkers and potential therapeutic targets in the clinical practice of CRC. In this review, we discuss the dysregulation, functions and clinical significance of circRNAs in CRC and further discuss the molecular mechanisms by which circRNAs exert their functions and how their expression is regulated. Based on this review, we hope to reveal the functions of circRNAs in the initiation and progression of cancer and highlight the future perspectives on strategies targeting circRNAs in cancer research.

Abstract Background The double lumen endotracheal tube (DLT) is the most widely-used device for single lung ventilation in current thoracic anesthesia practice. In recent years, the routine application of the videolaryngoscope for single lumen endotracheal intubation has increased; nevertheless there are few studies of the use of the videolaryngoscope for DLT. We wondered whether there were benefits to using the videolaryngoscope for DLT placement in patients with predicted normal airways. Therefore, this study was designed to compare the performances of the GlideScope®, the C-MAC®(D) videolaryngoscope and the Macintosh laryngoscope in DLT intubation. Methods This was a randomized, controlled, prospective study. We randomly allocated 90 adult patients with predicted normal airways into three groups. All patients underwent routine anesthesia using different laryngoscopes according to group allocation. We compared DLT insertion times, first-pass success rates, numerical rating scales (NRS) of DLT delivery and DLT insertion, Cormack-Lehane degrees (C/L), hemodynamic changes and incidences of intubation complications. All outcomes were analyzed using SPSS13.0. Results Compared with the GlideScope, the Macintosh gave shorter times for DLT insertion (median: 96 (IQR: 51 [min–max: 62–376] s vs 73 (26 [48–419] s, p = 0.003); however, there was no difference between the Macintosh and C-MAC(D) (p = 0.610). The Macintosh had a significantly higher successful first attempt rate than did the GlideScope or C-MAC(D) (p = 0.001, p = 0.028, respectively). NRS of DLT delivery and insertion were significantly lower in the Macintosh than in the others (p 0.05). There were no significant differences in DLT misplacement, fiberoptic time or hemodynamic changes among the groups. Conclusions Compared with the Macintosh laryngoscope, the GlideScope® and C-MAC®(D) videolaryngoscopes may not be recommended as the first choice for routine DLT intubation in patients with predicted normal airways. Trial registration The study was prospectively registered at the Chinese Clinical Trial Registry (no. ChiCTR1900025718 ); principal investigator: Z.L.H.; date of registration: September 6, 2019.

Due to the rapid advances of Information and Communication Technologies (ICT), especially 5G and Artificial Intelligence (AI), the Internet of Everything is gradually becoming a reality, and human beings living environments are becoming smarter and smarter. Every day there will be generated large amounts of data in Humans-Machines-Things hybrid space, which is also called Cyber-Physical-Social Systems (CPSSs). Today, the city we live in has become a data-driven society. However, how to effectively mine valuable information from these massive data to provide proactive and personalized services for human beings is a challenging problem. Thus, top-k search remains an important topic of ongoing research. In this paper, we focus on a basic problem of geo-tagged data: find the top-k frequent terms among the geo-tagged data in a specific region from the cloud. We first construct a Region Tree Index (RTI) for geo-tagged data. Then the list storage structure is proposed to Store Sorted Terms and Weights (SSTW) in RTI. And then an efficient kTermsSearch algorithm is presented to compute top-k frequent terms in a given region. Finally, extensive experiments verify the validity of the proposed scheme.

BackgroundFerroptosis is a newly defined form of programmed cell death that plays an important role in many cancers. However, ferroptosis-related lncRNAs (FRLs) involved in the regulation of colon cancer are not thoroughly understood. This study aimed to identify a prognostic FRL signature in colon cancer and explore its potential molecular function.MethodsRNA-seq data and relevant clinical information were obtained from The Cancer Genome Atlas (TCGA) database, and a list of ferroptosis-related genes was extracted from the FerrDb website. Analysis of differentially expressed FRLs was performed using the ‘limma’ package in R software. By implementing coexpression analysis and univariate Cox analysis, we then identified prognostic FRLs. Using Cox regression analysis with the least absolute shrinkage and selection operator (LASSO) algorithm, we constructed a prognostic model based on 4 FRLs. We evaluated the prognostic power of this model using Kaplan–Meier (K-M) survival curve analysis and receiver operating characteristic (ROC) curve analysis. Moreover, the relationships between the signature and immune landscape, somatic mutation and drug sensitivity were explored. Finally, in vitro experiments were conducted to validate the functions of AP003555.1 and AC000584.1.ResultsA 4-FRL signature was constructed. Two risk groups were classified based on the risk score calculated by this signature. The signature-based risk score exhibited a more powerful capacity for survival prediction than traditional clinicopathological features in colon patients. Additionally, we observed a significant difference in immune cells, such as CD4+ and CD8+ T cells and macrophages, between the two groups. Moreover, the high-risk group exhibited lower IC50 values for certain chemotherapy drugs, such as cisplatin, docetaxel, bleomycin or axitinib. Finally, the in vitro experiments showed that ferroptosis processes were suppressed after AP003555.1 and AC000584.1 knockdown.ConclusionThe proposed 4-FRL signature is a promising biomarker to predict clinical outcomes and therapeutic responses in colon cancer patients.

Abstract Two‐dimensional (2D) anisotropic rhenium diselenide (ReSe2) has attracted lots of attention due to its promising applications in electronics and optoelectronics. However, controlled synthesis of high quality ultrathin ReSe2 remains as a challenge. Here we developed an approach for synthesizing high quality 2D ReSe2 flakes with a thickness down to monolayer by chemical vapor transport (CVT) through carefully tuning the growth kinetics. The atomic structures and anisotropy of the obtained ReSe2 flakes were intensively characterized with scanning transmission electron microscope and angle‐resolved polarized Raman spectroscopy. Field‐effect transistors fabricated on the CVT‐grown ReSe2 flakes showed n‐type semiconducting behavior with an on/off current ratio of 105 and a mobility up to ∼5 cm2 V−1 s−1, which is comparable to mechanically exfoliated flakes and is obvious higher than the samples synthesized with other approaches. This study not only make high quality 2D ReSe2 easily accessible for both fundamental and application explorations but also sheds new lights on the chemical synthesis of other anisotropic 2D materials.

Identifying the crystallographic orientations of 2D materials is important, but methods to do so are typically destructive. Here, the authors show that the orientational dependency of self-assembled nanoribbons of oleamide molecules can be used to non-invasively probe the lattice orientations of various 2D substrates.

The original version of this Article omitted the following from the Acknowledgements: ‘Beijing Municipal Science & Technology Commission (No Z161100002116030)’ This has now been corrected in both the PDF and HTML versions of the Article.

This study investigated the effects of ant attendance on the parasitoid community and parasitism of lac insect Kerria yunnanensis aggregations in Yunnan province, China. We manipulated ant attendance to establish three treatments: (1) ant exclusion; (2) low ant attendance by several ant species; and (3) high ant attendance by Crematogaster macaoensis. Five parasitoid species were collected, with two species contributing 82.7 and 13.2% of total abundance respectively. Total parasitoid abundance was lowest in the February sample when K. yunnanensis was in its younger life stage, being significantly lower in the ant exclusion treatment. In April, all three treatments had significantly different parasitoid abundances, being highest in the ant exclusion treatment and the lowest in the high ant attendance treatment. When ants were present, there were strong negative relationships between total parasitoid abundance and ant abundance, with the relationships being dependent upon the ant species composition and abundance. The patterns of total parasitoid abundance were driven by the two most abundant parasitoid species. Parasitoid species richness did not differ among treatments or between sample times, however, multivariate analysis confirmed that overall parasitoid community structure differed significantly among treatments and between sample times, with the high ant attendance treatment differing most from the other two treatments. Interestingly the absence of ants did not result in increased parasitism from four of the five parasitoids. Ants in lac insect farming systems have a clear role for agricultural pest management. A full understanding of the asymmetric abilities of ants to influence parasitoid communities, and affect parasitism of hosts will require further experimental manipulation to assess the relative roles of 1) the abundance of each individual ant species on parasitoid access to hosts, 2) competition among parasitoids, and 3) the interaction between the first two factors.

Topic recommendation control aims to suggest relevant topics to users based on their preferences and regional trends. However, existing methods often lack effective measures to evaluate topic-user relevancy and require comparing large amounts of regional information, leading to low accuracy and efficiency. Therefore, we propose a Topic Recommendation Control method based on topic Relevancy and R-tree index (named as TRCRR) to address these limitations. TRCRR introduces a novel personalized topic relevancy metric that quantifies the relevancy between topics and user preferences. To improve efficiency, an R-tree topic index is constructed to organize topics across different regions hierarchically. Experiments on a real-world dataset show that TRCRR achieves better recommendation accuracy and efficiency compared to several baseline methods. The proposed approach offers a promising solution for personalized and region-aware topic recommendation. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) transition metal dichalcogenides (TMDCs) showed great potentials in 2D nanoelectronic devices due to their abundant and unique properties. The performance stability of the 2D TMDCs devices turns into one of the keys for their practical applications but has been rarely explored. Here, we investigated stability of MoS2 devices in ambient condition and contributed the device performance degradation to the surface oxidation of the contact metals with low work function, which increased the contact barrier and hindered the electron injection. We developed a new approach to recover the performance of the aged devices through the selective doping of contacts with organolithium, which prolonged the lifetime of MoS2 devices. Our work not only provides important insights into the stability of 2D TMDCs devices, but also opens up a new avenue for optimizing the performance of 2D MoS2 devices. [ABSTRACT FROM AUTHOR]

Solar radiation plays a pivotal role in urban microclimate, significantly, impacting building energy consumption and renewable energy utilization. Utilizing a comprehensive three- and-a- half-year dataset of high-precision urban microclimate, this study proposes a three-step approach to solar radiation prediction: 1) Data Preprocessing and Characterization: The microclimate data are meticulously preprocessed and categorized, with solar radiation values categorized into three resolutions: total daily solar radiation, hourly solar radiation, and 30-min solar radiation. 2) Feature Selection: Various climatic parameters are carefully selected for solar radiation prediction at different resolutions. 3) Machine Learning Models: Three machine learning models, namely Long Short-Term Memory (LSTM), Random Forest (RF) and Support Vector Regression (SVR), are employed for solar radiation prediction. The results show that all three models exhibit prediction accuracy with closely matched errors. Particularly noteworthy findings include SVR’s superior performance in predicting total daily solar radiation with a minimal error rate of about 6.0% and an impressive coefficient of determination of 0.9789. LSTM exhibits adaptability, achieving R2 values of 0.9906 and 0.9956 for hourly and 30-min radiation predictions, respectively. This study offers valuable insights into solar radiation and its implications for building energy research. It underscores that large datasets enable accurate solar radiation predictions, even when excluding certain parameters like daily maximum temperature and relative humidity.

As the first and second largest greenhouse gases (GHG) emissions industries, the sustainable development of construction and transportation industry determines the future of human society. The current carbon emission calculation standard does not cater to electrical transportation, as well as the characteristics of prefabricated components comparing with raw materials. This study focused on the transportation process of prefabricated components, exploring the characteristics of battery electric vehicles (BEV) in carbon emissions. Through the real-world experimental research, the true carbon emissions performance of components’ transportation was obtained under different external parameters. After preliminary screening of variables through correlation analysis, several variables were determined as compensation coefficient for multiple linear regression. The quantitative relationship between the three parameters of Load Ratio, Average Speed and Atmospheric Temperature on carbon emissions factor was revealed, and the R2 value of the fitting formula reached 0.7079(AC off). Results shows that BEV can reduce GHG emissions by 36.18%–54.69%. As well as promote the low-carbon innovation of the fabricated construction industry.

Several analytical models are employed to explain the nanomechanics of the graphene membranes, which are adhered to their substrates by the different van der Waals forces. The various equilibrium configurations and deformation regimes observed in these compounds are also analyzed.

CO2 foam injection has been shown to be effective under reservoir conditions for enhanced oil recovery. However, its application requires a certain stability and surfactant absorbability on rock surface, and it is also associated with borehole corrosion in the presence of water. Adding surfactants to CO2 can enhance the interaction between CO2 and crude oil and control the CO2 mobility, thereby improving the performance of CO2 flooding. This paper presents a review of the research of CO2-soluble surfactants and their applications. Molecular dynamics simulation is introduced as a tool for analyzing the behavior of the surfactants in supercritical CO2 (scCO2). The applications of CO2-soluble surfactants, including CO2 thickening, reducing miscibility pressure, and generating supercritical CO2 foam, are discussed in detail. Moreover, some opportunities for the research and development of CO2-soluble surfactants are proposed.

The mechanical robustness of atomic layer deposited alumina and the molecular layer deposited aluminum alkoxide (alucone) films are characterized by using mechanical tensile tests along with a fluorescent tag to visualize channel cracks in the transparent films. The modeling method is used for studying the increase in the toughness and elastic modulus of the space layer required to provide improved critical strain at fracture.

In this study, the period-n steady regions of McMullen family M sets are discussed. The calculation methods of the numbers of period-n steady regions are presented and the center points and boundaries of period-1 are studied by complex dynamical system theory. In addition, the problem about the free critical points is discussed. The experimental results show that the free critical points do not influence the distributions of period-n steady regions when m = d, which is proved theoretically. [ABSTRACT FROM AUTHOR]

Honeydew is a key resource for ants and a driver of ant community dynamics, yet we know very little about how the quantity of honeydew generates these patterns. This study investigated the effects of an ant-lac insect facultative association on ant community dynamics in a guild of ants attending Kerria yunnanensis (Hermiptera: Kerriidae) on its host plant Dalbergia obtusifolia in Yunnan Province, China. This was done by manipulating the access of ants to K. yunnanensis and the numbers of K. yunnanensis available. Regardless of the proportion of lac insect infestation (the ratio of the branch length infested by lac insects to the total branch length), there were more ant species and individuals under the ant-lac insect facultative association, and ant community composition was significantly different from that without this association. The level of branch infestation by the lac insect had a significant influence on the mean frequency of occurrence of ants; a low level of branch infestation by the lac insect led to low ant attendance. Honeydew secreted by the lac insect had a key role in structuring the ant community. There were more co-occurrences of ants under the ant-lac insect facultative association, and co-occurrence of more than three ant species only occurred on trees with lac insect infestation. The significant difference in frequency of month-by-month ant replacement was only observed in the treatment without lac insect hosting, which indicated the positive role of ant-lac insect association in stabilizing ant community. We suggest that the facultative association between ants and lac insects has conservation benefits for ant assemblages and provides a structuring mechanism for the ant community in the lac agroecosystem studied. [ABSTRACT FROM AUTHOR]

A courtyard is an essential space for natural lighting and natural convective ventilation of residential buildings in hot-humid climates. This study focuses on the internal courtyard configuration on the thermal performance of long strip houses (LSH) in the hot-climate area of Hainan Island, China. The aim is to identify the best design parameters for the courtyard to improve thermal comfort in modern LSH design. Appropriate strategies, including Mahoney table, field investigation, and CFD simulation, are used to determine thermal performance. As a result, the design guidelines of the courtyard are proposed to optimize the thermal comfort towards energy saving. The study reveals the spatial characteristics and climate regulation of internal courtyards in traditional LSH. In addition, the simulation results show that the enclosure with a shaded cover and a high ratio of H/D is conducive to thermal environment and ventilation, and the section of contracted shape from bottom to top is a preferred option in the internal courtyard configuration. This study should, therefore, be of value in designing practical projects with an interior courtyard for architects.

Porous alumina was prepared via a sacrificial template method using alumina as the matrix and starch and carbon fibers as the pore-forming agents. After sintering, no residual pore-forming agents were present. The density, porosity, and pore structure of the samples were measured using the Archimedes’ method and mercury intrusion porosimetry (MIP). The results showed that the pore size distribution of porous alumina was double-peak when the content of the pore-forming agent was 20, 30, or 50 vol.%, but was single-peak when the content was 40 vol.%. A fractal model based on the measured MIP data was used to calculate and evaluate the fractal dimension (Ds) of porous alumina. The Ds values decreased with an increase in the pore-forming agent content. Furthermore, Ds was negatively correlated with porosity, most probable pore size, and median pore diameter and positively correlated with the bending strength of porous alumina. Since porous alumina has obvious fractal characteristics, the fractal theory can be used to quantitatively describe its complex distribution.

US Sec of State James A. Baker's recent trip to the Middle East was aimed at promoting the peace process in the region. Baker's itinerary took him to Israel, Egypt, Jordan, Syria, Lebanon and Saudi Arabia. Talks were held with top officials of these countries. Baker also met with representatives of the the Palestinians in the Israeli-occupied territories and successfully arrange a new set of talks between Israeli and Arab leaders. The new set of talks is expected to focus on the right of Palestinians to limited self-rule in the occupied territories.

This study employed the bottom-up life cycle assessment method, examining the life cycle carbon emissions of three dwellings constructed at different times with different techniques in Yinchuan City, China, i.e. traditional earth brick dwelling (Case 1), brick–straw bale dwelling (Case 2), wood–straw solar energy dwelling (Case 3). The study aimed to find the methods of reducing carbon emissions, so as to slow down the global warming. The results showed that (1) with excellent thermal insulation properties, straw bale was remarkably effective in reducing carbon emissions from heating at the use stage; (2) 15 kWp solar photovoltaic panels contributed to offsetting the carbon emission of the dwelling; (3) straw bales and logs could store the carbon in building envelope, which partly offset the carbon emissions. The findings of this study have proved that ecological building materials and solar photovoltaic system have great potential in reducing carbon emissions of buildings, and can provide a basis for the design and material selection of future dwellings in order to promote the development of green dwellings.

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Thermal performance is considered to be a key measure in building sustainability. One of the technologies used in the current building sustainable design is the high thermal mass techniques. The application of this type of technology is widely used in traditional architecture. The paper aims at studying the effect of both high thermal insulation and high thermal mass techniques in buildings dynamic behaviour in Dry-Hot and Dry-Cold Climate. The two techniques can lead to conflicting requirements when considering winter and summer conditions. Therefore, it is necessary to identify insulation measures that conserve the mass dynamic behavior. Experimental investigations were carried out on a single - family house to characterize the behavior of one room with high thermal mass in different seasons. Thermal simulations made it possible to explore different retrofit configurations. Different thermal mass and thermal insulation were compared on internal surface temperature. The analysis shows that the most suitable intervention is both high thermal insulation and high thermal mass techniques, and the decrease of the absorption coefficient of the outer surface is beneficial to improve the overall level of solar radiation.

In this work, the vertical electrical transport behavior of bilayer MoS2 under the coupling of force and light was explored by the use of conductive atomic force microscopy. We found that the current–voltage behavior across the tip–MoS2–Pt junction is a tunneling current that can be well fitted by a Simmons approximation. The transport behavior is direct tunneling at low bias and Fowler–Nordheim tunneling at high bias, and the transition voltage and tunnel barrier height are extracted. The effect of force and light on the effective band gap of the junction is investigated. Furthermore, the source–drain current drops surprisingly when we continually increase the force, and the dropping point is altered by the provided light. This mechanism is responsible for the tuning of tunneling barrier height and width by force and light. These results provide a new way to design devices that take advantage of ultrathin two-dimensional materials. Ultrashort channel length electronic components that possess tunneling current are important for establishing high-efficiency electronic and optoelectronic systems. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) transition metal dichalcogenides (TMDCs) with layered structures provide a unique platform for exploring the effect of number of layers on their fundamental properties. However, the thickness scaling effect on the chemical properties of these materials remains unexplored. Here, we explored the chemically induced phase transition of 2D molybdenum disulfide (MoS2) from both experimental and theoretical aspects and observed that the critical electron injection concentration and the duration required for the phase transition of 2D MoS2 increased with decreasing number of layers. We further revealed that the observed dependence originated from the layer-dependent density of states of 2H-MoS2, which results in decreasing phase stability for 2H-MoS2 with increasing number of layers upon electron doping. Also, the much larger energy barrier for the phase transition of monolayer MoS2 induces the longer reaction time required for monolayer MoS2 as compared to multilayer MoS2. The layer-dependent phase transition of 2D MoS2 allows for the chemical construction of semiconducting-metallic heterophase junctions and, subsequently, the fabrications of rectifying diodes and all 2D field effect transistors and thus opens a new avenue for building ultrathin electronic devices. In addition, these new findings elucidate how electronic structures affect the chemical properties of 2D TMDCs and, therefore, shed new light on the controllable chemical modulations of these emerging materials. [ABSTRACT FROM AUTHOR]