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TEM image of Au-In 2 O 3 -co-decorated WS2 NSs; Selectivity pattern of Au-IN 2 O 3 -co-decorated WS 2 gas sensor to various gases under fixed 6.2 V applied voltage to 50 ppm. [Display omitted] • Co-decoration of Au and In 2 O 3 NPs on WS 2 nanosheets. • CO gas sensing at different applied voltages in self-heating mode. • Co-decorated gas sensor showed a response of 3.24 to 50 ppm CO gas at 6.2 V. • Explanation of the underlying sensing mechanism. Two-dimensional materials such as WS 2 nanosheets (NSs) have unique merits such as high surface area, good conductivity at low temperatures and good chemo-physical stability. In this study, we co-decorated In 2 O 3 and Au NPs on WS 2 NSs for CO gas sensing studies. The fabricated sensors were used in self-heating mode of operation at 25 °C, which can significantly decrease the power consumption. It was found that co-decorated gas sensor not only operates at a lower applied voltage, but also exhibits a higher sensing performance (sensitivity and selectivity), relative to bare WS 2 NSs. On one hand, generation of In 2 O 3 -WS 2 heterojunctions acted as notable sources of the resistance modulation and on the other hand, Au with its catalytic effect, significantly enhanced the dissociation of oxygen molecules and also offers many favorable adsorption sites for CO molecules. Therefore, we believe that co-decoration of WS 2 is a reliable strategy to enhanced the sensing features in self-heating mode, which is highly demanded for devices with reduced power consumption. [ABSTRACT FROM AUTHOR]

Low-temperature operating chemiresistive gas sensors are attractive for a variety of real-time gas monitoring applications, with benefits such as low power consumption, profitability, and miniaturization of devices. In this regard, we developed a low-temperature operating H 2 gas sensor using solvothermal-processed novel amine-functionalized zinc-based metal-organic framework (Zn-BDC-NH 2) as a detection material. The Zn-BDC-NH 2 structure is consists of the Zn 4 O secondary building units and 2–aminoterephthalate acidic linker that form the 3D frame structure. Prior to sensing studies, various techniques were employed to confirm -NH 2 functionalization and to characterize structure, surface morphology, thermal stability, surface area, and surface chemistry of synthesized Zn-BDC-NH 2 materials. Benefitting from the simple synthesis process and larger surface area (880 m2g-1) with adequate porosity (~13 Å), Zn-BDC-NH 2 has proven to be an excellent chemiresistive sensor for the effective sensing of low concentrations of H 2 at 50 °C. Moreover, the sensor shown significant sensitivity to the detection of lower H 2 concentrations of 1–10 ppm, a response value of 2.93–10 ppm H 2 , and complete recovery characteristics at 50 °C. We discussed the mechanisms for attaining the excellent H 2 sensing. The utilized room temperature solvothermal approach opens up a perspective for synthesizing Zn-BDC-NH 2 material with suitable functionalities and their use in low temperature H 2 sensors. [Display omitted] • A highly effective H 2 gas sensor using a novel Zn-BDC-NH 2 as the detection material was developed. • Solvothermal-processed Zn-BDC-NH 2 features an ultra-high surface area of 880 m2g-1. • Zn-BDC-NH 2 was an excellent sensor for the selective detection of low-concentration H 2 at 50 °C. • Adding -NH 2 groups to Zn-BDC MOFs increased the binding energy for H 2 gas, ultimately improving H 2 adsorption. [ABSTRACT FROM AUTHOR]

• Aging treatments were performed for tailoring the precipitation behavior in the SLM-built Cu-Ni-Sn-P alloy. • Yield strength was significantly improved in the 2 h sample more than three times compared to that of as-homogenized sample. • Aged samples shows a higher thermal conductivities than as-homogenized sample. This study investigated ways to improve both the mechanical and thermal properties of a Cu-Ni-Sn-P alloy manufactured with selective laser melting (SLM) using aging treatment. Homogenization heat treatment was conducted to the alloy at 820 °C for 12 h, and aging heat treatment was applied at 400 °C for 0.25, 0.5, 1, 2 and 4 h. Initial microstructure analysis identified (Cu, Ni) 3 P phase precipitates of a few μm in size, and the size and fraction of precipitates increased as aging heat treatment time increased. Room temperature compressive tests on the homogenized sample identified a yield strength of 135.7 MPa. Meanwhile, the yield strength of the sample that underwent 2-hour aging treatment measured 454.5 MPa, indicating a three times greater improvement of the mechanical properties than the homogenized sample. This was confirmed to have been contributed by precipitation hardening from the increased precipitate size and fraction as a result of aging treatment. In addition, thermal conductivity also increased as aging treatment was performed. In particular, an aging time greater than 2 h achieved an approximately 30% increase in thermal conductivity compared to the homogenized sample. Through aging treatment, both the mechanical property and thermal conductivity of an SLM-built Cu-Ni-Sn-P alloy were improved. Based on these findings, this study also discussed the underlying mechanisms according to aging time with respect to microstructural changes. [ABSTRACT FROM AUTHOR]

Abstract: Telematics service is a rapidly evolving mobile commerce service in the early stages of its diffusion. This study examines consumer preferences for transport telematics services over time in terms of service features and purchasing time by conjoint analysis and the rate of time preference (RTP) method. Our empirical results prove that an upgraded navigation-traffic information service and the vehicle relationship management (VRM) service are the most important factors for both current and potential consumers and that timing of these services has a negative impact on consumer preferences. [Copyright &y& Elsevier]

This work demonstrates the potential of a novel iron-based metal-organic framework (Fe-MOF or VNU-15) to effectively detect low-concentration volatile organic compounds (VOCs), particularly acetone (CH 3 COCH 3). A facile solvothermal strategy was used to synthesize Fe-MOFs, comprising Fe(II)/Fe(III) and two distinct linkers—BDC (benzene-1,4-dicarboxylate) and NDC (naphthalene-2,6-dicarboxylic acid). As a first step, Fe-MOFs were characterized to determine their pure phase formation and identify their structural and morphological characteristics. Fe-MOFs processed via the solvothermal method demonstrated high crystallinity, high thermal stability, polyhedral crystal-shaped surface morphology, and a surface area of 735 m2g−1, making them suitable for gas-sensing applications. Laboratory-scale gas-sensing devices were fabricated by printing Fe-MOF powder onto patterned interdigitated electrodes, with performance measurements conducted on these devices in response to exposure to various target gases at temperatures between 25 and 200 °C and gas concentrations between 1 and 10 ppm. Gas-sensing tests confirmed that the VNU-15 sensor selectivity detects CH 3 COCH 3 with a gas response of 1.68–10 ppm and a response time of 64 s, followed by a recovery time of 166 s at 50 °C. This study demonstrates the feasibility of using novel MOF-based sensing channels as low-temperature gas sensors, providing new insights into gas-sensing technology. • Facile low-temperature solvothermal synthesis approach of Fe-MOFs with ultra-high surface area of 735 m2g−1. • The use of Fe-MOFs as an active gas-sensing material has been demonstrated. • Fe-MOF has proven to be an excellent chemiresistive material for detecting low-level CH 3 COCH 3 at 50 °C. • Fe-MOF detects 1 ppm CH 3 COCH 3 , being lower than the breath value for people with diabetes. [ABSTRACT FROM AUTHOR]

This study proposes a solvothermal method for synthesizing sulfate-functionalized hafnium-organic frameworks (Hf-BTC-SO 4) for application in low-temperature NH 3 gas sensors. Prior to the gas-sensing studies, solvothermal-processed Hf-BTC-SO 4 is characterized using various techniques to obtain structural, elemental, morphological, and thermal stability information. Results of structural and thermal-stability analysis demonstrate that Hf-BTC-SO 4 exhibits good crystallinity and high thermal stability with the functionalization of SO 4 in the Hf-framework. Microstructural analysis reveals that nanoparticles aggregated to form compact clusters of Hf-BTC-SO 4. In addition, Hf-BTC-SO 4 has an ultra-high specific surface area of 1100 m2g−1 (with a pore size of 15 Å), suitable for gas detection owing to enhanced surface reactions. Gas-sensing studies confirm that the fabricated Hf-BTC-SO 4 sensor exhibits selective detection of NH 3 gas at a lower working temperature of 100 ºC. Notably, the Hf-BTC-SO 4 sensor detected up to 1 ppm of NH 3 (response = 1.41), with excellent response reversibility. The functionalized sulfate bonds and Hf-clusters within the framework form strong bonds with NH 3 , enhancing their interaction with the metal-organic frameworks. This study can motivate future research on the synthesis of functional organic frameworks for applications in low-temperature NH 3 detection devices. [Display omitted] • A novel sensing material based on Hf-BTC-SO 4 was synthesized and characterized as a chemiresistive gas sensor. • As-synthesized Hf-BTC-SO 4 features an ultra-high surface area of 1100 m2g−1. • Hf-BTC-SO 4 sensor showed a selective detection of NH 3 gas at a low temperature of 100 ºC. • Functionalized sulfate bonds and Hf-clusters enable NH 3 molecules to adsorb by strong host-guest interactions to realize low-level NH 3 detection. [ABSTRACT FROM AUTHOR]

[Display omitted] • Enhancement of the humidity resistance of the semiconductor metal oxide gas sensors. • Coating of SnO 2 nanowires (NWs) with a humidity resistant nanomembrane. • Molecular layer deposition (MLD) was used for the synthesis of the nanomembrane. • The membrane coated SnO 2 NWs gas sensors shows a remarkable gas response under humid conditions. • The sensor showed stability and repeatability in humid conditions like relative humidity (RH %) 30 and 90 %. We report a novel route for enhancing the humidity resistance of SnO 2 nanowires (NWs; widely used metal oxide semiconductor gas sensors) based on their coating with a humidity-resistant nanomembrane. A conformal thin film was deposited by Molecular Layer Deposition (MLD) on the SnO 2 NWs using trimethylaluminum and ethylene glycol as precursors (100 MLD cycles), followed by oxidation in air at 400 °C. In conditions of increasing relative humidity, the SnO 2 NW gas sensor coated with a microporous, 10-nm thick nanomembrane layer of converted alucone obtained by MLD and calcination showed a remarkable gas response compared with the pristine SnO 2 NW gas sensor. This sensor was stable and displayed good recovery times in humid conditions (30 and 90 % of relative humidity). This work shows the benefits and the practical application of MLD-prepared nanomaterials. This original strategy applied to NW-based gas sensors paves the way for other complex 3D designs and different applications that require gas or ion selectivity, such as photocatalysts and biosensors, in humid atmosphere. [ABSTRACT FROM AUTHOR]

With the rising adoption of BIM in the AECO (Architecture, Engineering, Construction and Owner-operator) industry, BIM content is increasingly more complete and valuable. Unfortunately, the data is largely locked inside the respective BIM authoring tool with limited facility for users to perform queries beyond simple queries on objects and their properties. Even with the use of open data exchange format such as IFC (Industry Foundation Classes), getting the data out of BIM is still not an easy task. This research focuses on defining a schema and transformation rules to bring BIM data into a form that is easily queried. The schema is defined using popular relational database structure following an established star schema model that is well-defined within the data warehouse domain. The primary aim of the concept is to allow flexible and efficient queries into the BIM data using standard SQL that removes restrictions on predefined queries, effectively transforming BIM data into an open and queryable database. Another major contribution of this research is the significant potential for supporting spatial queries. This is a critical feature often neglected in the current approach to BIM-based databases. This paper presents the integration of spatial operations into standardized SQL queries making the BIM data accessible for wide ranges of query capabilities. Such feature will allow much better visibility into BIM data for better decision-making processes. [ABSTRACT FROM AUTHOR]

Background Colorectal cancer (CRC) has been known to complicate Crohn’s disease (CD). Several reports in Western population revealed that CRC in CD were characterized by much younger onset and equal distribution of tumors along the entire colon. However, clinicopathologic features of CD-associated CRC in Korean population have not been well documented yet. Methods Among 2968 Korean CD patients, 16 patients (0.54%) were found to develop CRC during follow up. We reviewed clinicopathologic features of the 16 CRC patients. Results The mean age at the time of CRC diagnosis was 39.3 years (range 18–59 years) and 14 of the 16 CRCs (87.5%) occurred in anorectal region. Mucinous adenocarcinoma was strikingly frequent (9/16, 56.3%) and eight cases (8/9) of the mucinous adenocarcinoma cases were located at anorectal area. The other cases consisted of 4 tubular adenocarcinomas, 2 signet ring cell carcinomas and 1 neuroendocrine tumor. Thirteen patients (81.3%) had a history of perianal fistula and 8 of them had a histological association between the CRC and the perianal fistula. Conclusions CD-associated CRC was characterized by young age at diagnosis, mucinous histology and association with perianal fistula in Korean patients. [ABSTRACT FROM AUTHOR]

Western-style diet (WD) and dysbiosis are known to be associated with colonic inflammation, which contributes to carcinogenesis. Metformin (Met) exerts anti-inflammatory effects to induce AMP-activated protein kinase (AMPK), resulting in suppressed protein synthesis and reduced cell proliferation. Probiotic VSL#3 (V) modifies microbial composition. We investigated the chemopreventive mechanisms of Met and V in WD-induced colitis-associated colon carcinogenesis. Male BALB/c mice were randomly divided into five groups: a control diet (CD) group, WD group, WD+ Met (250 mg/kg/day) group, WD+V (1.3 million bacteria/day) group, and WD+Met+V group. All mice were exposed to azoxymethane (10 mg/kg) followed by 2% dextran sodium sulfate (DSS) for 7 days. Using HCT-116 human colon cancer cell line, expression of AMPK, extracellular signal-regulated kinase ( ERK), cyclin D1, and Bcl-2 was investigated and cell cycle arrest was assessed. WD enhanced the severity of colitis and tumor growth compared with CD. The combination of Met and V significantly ameliorated colitis and tumor growth by inhibiting macrophage infiltration and maintaining epithelial integrity. In vitro assays showed that the combination therapy promoted late apoptosis by inhibiting cyclin D1 and Bcl-2 and activating pro-apoptotic ERK. A combination therapy with Met and V attenuates tumor growth in a mouse model of WD-induced colitic cancer, suggesting that this strategy could be useful for the chemoprevention of colon cancer. [ABSTRACT FROM AUTHOR]

The effect of shell thickness and noble metal decoration on the gas-sensing characteristics of two-dimensional (2D) materials has not been reported yet. Herein, we synthesized 2D pristine and Au-decorated WS 2 -SnO 2 core-shell nanosheets (Au NSs). SnO 2 shells with various thicknesses (up to 60 nm) were deposited on the WS 2 NSs. Subsequently, Au was deposited on the synthesized WS 2 -SnO 2 core-shell NSs (WS 2 -SnO 2 NSs) under UV irradiation. Flexible polyamide substrates were used to fabricate gas sensors, which operated in self-heating mode upon applying different voltages for CO detection. Bare and Au-decorated gas sensors with shell thicknesses of 15 and 30 nm revealed the highest CO sensing performance at a low voltage of 3.4 V. The flexibility of the gas sensors was demonstrated by the negligible degradation of the sensing performance after 10,000 bending cycles. We also evaluated the sensing characteristics under humid conditions. The developed gas sensors with very low applied voltage and high performance for CO gas sensing are very promising for commercial applications. • We synthesized Au-decorated WS 2 -SnO 2 core-shell nanosheets on flexible polyamide substrates. • Sensors were operated in self-heating mode upon applying different voltages for CO detection. • Au-decorated gas sensors with shell thicknesses of 30 nm indicated the highest response to CO gas at 3.4 V. • Formation of heterojunctions and the promising effect of Au NPs led to enhanced sensing. [ABSTRACT FROM AUTHOR]

The effect of shell thickness and noble metal decoration on the gas-sensing characteristics of two-dimensional (2D) materials has not been reported yet. Herein, we synthesized 2D pristine and Au-decorated WS 2 -SnO 2 core-shell nanosheets (Au NSs). SnO 2 shells with various thicknesses (up to 60 nm) were deposited on the WS 2 NSs. Subsequently, Au was deposited on the synthesized WS 2 -SnO 2 core-shell NSs (WS 2 -SnO 2 NSs) under UV irradiation. Flexible polyamide substrates were used to fabricate gas sensors, which operated in self-heating mode upon applying different voltages for CO detection. Bare and Au-decorated gas sensors with shell thicknesses of 15 and 30 nm revealed the highest CO sensing performance at a low voltage of 3.4 V. The flexibility of the gas sensors was demonstrated by the negligible degradation of the sensing performance after 10,000 bending cycles. We also evaluated the sensing characteristics under humid conditions. The developed gas sensors with very low applied voltage and high performance for CO gas sensing are very promising for commercial applications. • We synthesized Au-decorated WS 2 -SnO 2 core-shell nanosheets on flexible polyamide substrates. • Sensors were operated in self-heating mode upon applying different voltages for CO detection. • Au-decorated gas sensors with shell thicknesses of 30 nm indicated the highest response to CO gas at 3.4 V. • Formation of heterojunctions and the promising effect of Au NPs led to enhanced sensing. [ABSTRACT FROM AUTHOR]