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The paper investigates the effect of the property taxation reform introduced in Sweden from 2006 to 2008 on the market price of the affected properties (one-family houses). We make an extensive empirical analysis of the tax capitalization effect, given that prior research has detected only partial capitalization and that there has been an extensive debate regarding the extent to which the tax gets capitalized into property market prices. In particular, the tax capitalization effect for single-family house prices was investigated by looking into various sub-groups of properties and doing extensive statistical inquiries into the property transaction data. Despite a relatively broad time period in which the reform took place, a jump in the market values of the affected properties is detectable in the fourth quarter of 2006. Our findings emphasise the importance of creating a representative data sample in analyzing and assessing the outcomes and impacts of policy interventions such as a taxation reform.

The COVID-19 pandemic is an ongoing global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2020–2021. COVID-19 is becoming one of the most fatal pandemics in history and brings a huge challenge to the global healthcare system. Opportune detection, confinement, and early treatment of infected cases present the first step in combating COVID-19. Diagnosis via viral nucleic acid amplification tests (NAATs) is frequently employed and considered the standard procedure. However, with an increasing urge for point-of-care tests, rapid and cheaper immunoassays are widely utilized, such as lateral flow immunoassay (LFIA), which can be used for rapid, early, and large-scale detection of SARS-CoV-2 infection. In this narrative review, the principle and technique of LFIA applied in COVID-19 antigen and antibody detection are introduced. The diagnostic sensitivity and specificity of the commercial LFIA tests are outlined and compared. Generally, LFIA antigen tests for SARS-CoV-2 are less sensitive than viral NAATs, the “gold standard” for clinical COVID-19 diagnosis. However, antigen tests can be used for rapid and mass testing in high-risk congregate housing to quickly identify people with COVID-19, implementing infection prevention and control measures, thus preventing transmission. LFIA anti-SARS-CoV-2 antibody tests, IgM and/or IgG, known as serology tests, are used for identification if a person has previously been exposed to the virus or vaccine immunization. Notably, advanced techniques, such as LFT-based CRISPR-Cas9 and surface-enhanced Raman spectroscopy (SERS), have added new dimensions to the COVID-19 diagnosis and are also discussed in this review.

COVID‐19 has brought speculations on potential transmission routes of the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), the causal agent of the pandemic. It is reported that the main route of virus transmission to be person‐to‐person by respiratory droplets; however, people have raised concerns on the possible transmission of SARS‐CoV‐2 to humans via food and packaging and its potential effects on food safety. This review discusses food safety issues in the COVID‐19 pandemic and reveals its possible transmission in cold‐chain food. The first outbreak of COVID‐19 in late 2019 was associated with a seafood market in Wuhan, China, while the second outbreak of COVID‐19 in June 2020 was also related to a seafood market in Beijing, China. As of 2020, several frozen seafood products linked with SARS‐CoV‐2 have been reported in China. According to the current survey and scientific studies, the risk of infection by SARS‐CoV‐2 from cold‐chain food, food products, and food packaging is thought to be very low. However, studies on food cold chain contamination have shown that SARS‐CoV‐2 remained highly stable under refrigerated (4°C) and even in freezing conditions (−10 to −80°C). Since one mode of SARS‐CoV‐2 transmission appears to be touching contaminated surfaces, it is important to clean and sanitize food contact surfaces properly. Understanding food safety hazard risks is essential to avoid potential negative health effects and SARS‐CoV‐2 transmission in the food supply chain during the COVID‐19 pandemic., Probable route of transmission for SARS‐CoV‐2 through cold‐chain transportation in the frozen food industry.

Wen-Sheng Tzeng,1,2 Wei-Lin Teng,3 Pao-Hsien Huang,4 Tzu-Ching Lin,3 Feng-Lin Yen,2,5– 7 Yow-Ling Shiue2 1Department of Radiology, Pingtung Christian Hospital, Pingtung, Taiwan; 2Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung, Taiwan; 3Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan; 4School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan; 5Department of Fragrance and Cosmetic Science, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan; 6Drug Development and Value Creation Research Center, Kaohsiung Medical University, Kaohsiung, Taiwan; 7Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung, TaiwanCorrespondence: Feng-Lin YenDepartment of Fragrance and Cosmetic Science, College of Pharmacy, Kaohsiung Medical University, No.100, Shin-Chuan 1st Road, Sanmin Dist., Kaohsiung City, 80708, TaiwanTel +886 7 3121101 ext 2028Email flyen@cc.kmu.edu.twYow-Ling ShiueInstitute of Biomedical Sciences, National Sun Yat-Sen University, No 70 Lien-Hai Road., Kaohsiung City, 80424, TaiwanTel +886 7 5252000 ext 5818Email shirley@imst.nsysu.edu.twPurpose: Transcatheter arterial chemoembolization (TACE) is a common clinical treatment for hepatocellular carcinoma (HCC). However, hypoxia induction after treatment might trigger tumor invasiveness and metastasis. Although pterostilbene (PTS) has antitumor effects, its chemoprevention in HepG2 cells under hypoxia has not been investigated yet. In addition, the poor water solubility of raw PTS limits its clinical application. Here, we prepared nanoparticles of PTS (PSN) and compared their antihepatoma activities with those of raw PTS in HepG2 under hypoxic conditions.Materials and Methods: The PTS nanoparticle formulation was prepared by nanoprecipitation, using Eudragit® e100 (EE) and polyvinyl alcohol (PVA) as carriers. We analyzed the physicochemical properties of raw PTS and PSN, including yield, encapsulation efficiency, water-solubility, particle size, morphology, crystalline-to-amorphous transformation, and molecular interaction between PTS and carriers. We also evaluated their antihepatoma activities under hypoxia treatment in HepG2 cells, including cell viability, hypoxia, and apoptosis.Results: The yield and encapsulation efficiency of PSN were 86.33% and > 99%, respectively. The water solubility and drug release of PTS were effectively improved after nanoprecipitation corresponding to the reduction in particle size, amorphous transformation, and formation of hydrogen bonding with carriers. PSN had a better cytotoxic effect than raw PTS in HepG2 under pre- and post-hypoxia conditions. In addition, hypoxia- and apoptosis-related proteins in HepG2 cells under two different hypoxic conditions were significantly inhibited by PSN compared with the control group with hypoxia only, except for HIF-1α in the post-hypoxia group. PSN was also significantly better in inhibiting these proteins, except for Bcl2, under pre-hypoxic conditions.Conclusion: Our results suggested that PSN could improve the water solubility and drug release of PTS and enhance the efficacy of HCC treatment under hypoxic conditions.Keywords: hepatocellular carcinoma, hypoxia, transcatheter arterial chemoembolization

Resveratrol is a naturally occurring polyphenol compound which has been shown to possess antioxidant and anti-inflammatory properties. However, its pharmaceutical applications are limited by its poor water solubility. In this study, we used electrospinning technology to synthesize nanofibers of polyvinylpyrrolidone (PVP) and hydroxypropyl-&beta, cyclodextrin (HPBCD) loaded with resveratrol. We used X-ray diffractometry to analyze crystalline structure, Fourier transform infrared spectroscopy to determine intermolecular hydrogen bonding, antioxidant assays to measure antioxidant activity, and Franz diffusion cells to evaluate skin penetration. Our results showed that the aqueous solubility of resveratrol nanofibers was greatly improved (by more than 20,000-fold) compared to the pure compound. Analysis of physicochemical properties demonstrated that following nanofiber formation, resveratrol was converted from a crystalline to amorphous structure, and resveratrol formed new intermolecular bonds with PVP and HPBCD. Moreover, resveratrol nanofibers showed good antioxidant activity. In addition, the skin penetration ability of resveratrol in the nanofiber formulation was greater than that of pure resveratrol. Furthermore, resveratrol nanofibers suppressed particulate matter (PM)-induced expression of inflammatory proteins (COX-2 and MMP-9) in HaCaT keratinocytes. Therefore, resveratrol-loaded nanofibers can effectively improve the solubility and physicochemical properties of resveratrol, and may have potential applications as an antioxidant and anti-inflammatory formulation for topical skin application.

The emerging literature suggests that mega-sporting events have the potential to negatively impact local ecosystems by causing pollution and waste accumulation. This has raised the issue of “green sports,” which is a critical one. This study attempts to contribute a model to the design process to identify factors that attract spectators to sports, provide insights into the dynamics of mega-sporting events, and present a set of sustainable products that could interest sports-goers. A baseball game was selected as an example of a mega-sporting event. The study employed a combined model of the design process for product innovation, which included two in-depth qualitative interview methods: the evaluation grid method and a user journey map. A set of products designated as the “HOMERUN” set were designed based on the findings of the combined model. The result illustrated the possibility of transforming product features to meet users’ needs at different stages of the mega-sporting experience. The model applied in this study has implications for transforming product design thinking from a focus on specific points in problem solving to a linear pattern that focuses on a broader picture.

The electrochromic, photodegradation, and photoinduced hydrophilicity properties of the WO3/TiO2 core–shell nanostructure as a smart building material for energy-saving are investigated. The core–shell nanostructure exhibits a highly reduced ion intercalation capacity with good reversible electrochemical cycling of intercalation–deintercalation, and shows a higher coloration efficiency (110.8 cm2 C−1), faster switching speed (0.7 s and 2.9 s) and better cycling performance than as-deposited WO3 nanowires (NWs). The TiO2 shell layer greatly enhanced the photocatalytic oxidation activity of WO3 NWs, increasing the photoinduced hydrophilic conversion. The enhanced photocatalytic reaction by the core–shell structure was attributed to the multi-electron reduction in the interlayer, caused by the electrons injected from the conduction band of the WO3 NWs. These results suggest that the WO3/TiO2 core–shell nanostructure enhances the electrochromic, photodegradation, and photoinduced hydrophilicity properties due to the increased density of charge separated electron–hole pairs aided by the TiO2 and WO3 interlayer. The WO3/TiO2 core–shell structure was found to possess superior properties giving it good potential for use in energy-saving smart windows.

In this paper, we employ a series of metal-assisted chemical etching processes to fabricate low-cost silicon nanohole (SiNH) and silicon nanowire (SiNW) arrays for hybrid solar cells. The SiNH arrays and SiNW arrays are obtained by a two-step etching and one-step etching technique, respectively. Length and depth of SiNWs and SiNHs can be controlled by etching time. The SiNH arrays demonstrate higher optical trapping effect than SiNW arrays, resulting in leading performance power conversion efficiency of 11.25% in the hybrid organic–inorganic solar cells. SiNH arrays have a high surface area, compared to SiNW arrays, so they can give rise to more junction area in the organic–inorganic heterojunction structures. In addition, these SiNH arrays possess additional advantages of robust structures and higher density with low air-filling fraction as compared to SiNW arrays. Furthermore, the SiNH arrays show superior efficiency to SiNW arrays experimentally. In particular, the fabricated SiNH arrays with high density can suppress the optical reflection well below 5% over a broad wavelength range from 300 to 1100 nm in a short nanohole depth. The very low reflectance and excellent light trapping property are attributed to the sub-wavelength dimension of the SiNH structure. These SiNH arrays not only facilitate the optical trapping, but also provide efficient broadband and omnidirectional photon harvests for cost-effective future nanostructured photovoltaics.

A grass-like carbon nanotube/nickel (CNT/Ni) sensor treated by microwave (MW) technique to enhance hydrogen (H 2 ) gas-sensing response was used. A leaf-like CNT/Ni nanostructure was changed into a grass-like CNT/Ni nanostructure through the MW treatment technique in order to enhance the H 2 sensor response. The H 2 gas sensing characteristics of grass-like CNT/Ni were found to have a much higher sensor response of ∼11% at 1000 ppm H 2 gas, approximately 33 times greater than that of leaf-like CNT/Ni (∼0.33%) without MW treatment. The MW technique is simple, energy-efficient at low temperature (58 °C), and effectively enhances the sensing response of CNT/Ni sensors.

A facile approach is developed to easily fabricate field emission (FE) cathodes based on TiO 2 nanotubes with different geometrical structures at low temperature. Planar TiO 2 nanotubes (P-TNTs) are first synthesized using the electrochemical anodization process with applied voltages of 20–50 V for 1 h at room temperature followed by thermal oxidation at 280 °C for 2 h under atmosphere ambient. P-TNTs can be transformed into aggregated TiO 2 nanotubes (A-TNTs) after H 2 O 2 post-treatment for 1 h at room temperature. FESEM, XRD, and Raman spectroscopy were used to analyze the surface morphology, crystallinity, and chemical binding, respectively. The A-TNTs fabricated with the applied voltages of 30–50 V cathodes possess higher levels of FE properties (lower turn-on electric field and higher current density) than the other cathodes due to their greater number of emission sites and decrement of the screening effect. The A-TNT with an applied voltage of 40 V cathode exhibits the lowest turn-on electric field (4.87 V/μm, 1 μA/cm 2 ) and the highest enhancement factor β (1486). These superior properties indicate that the A-TNTs are promising field cathodes for future FE applications.

Tungsten oxide is an n-type semiconductor with interesting physical and chemical properties that make it suitable for various technological applications. Tungsten oxide nanowires were synthesized not only at low temperature but also without the use of any catalysts. The tungsten oxide nanowires were synthesized at 550 °C with tungsten layers onto the ITO glass using thermal chemical vapor deposition (T-CVD). The SEM image shows that the tungsten oxide nanowires are effectively grown with the 200 nm tungsten film. The Raman spectra shoulder at ~690 cm-1 proves the synthesized of tungsten oxide nanowires.

A hybrid structure of graphene sheets (GSs)/ZnO nanorods (ZNRs) is developed on glass substrates for applications in field emission (FE) cathodes. ZNRs are grown on glass substrates by a combination of sputtering and hydrothermal processes. Graphene films are synthesized on the Cu foils by the thermal chemical vapor deposition technique, and are transferred onto the ZNRs with various cycles (one, two, and three times) to form GS/ZNR hybrids with different morphology. FESEM, XRD, and Raman spectroscopy are used to analyze the surface morphology, crystallinity, and chemical composition, respectively. It is found that the FE properties of all GS/ZNR cathodes possess a lower turn-on electric field and higher current density than pristine ZNR cathode owing to the presence of the GS. The GSs/ZNRs with two transferred cycle exhibit the lowest turn-on electric field (3.7 V/μm, 1 μA/cm 2 ) and highest enhancement factor β (8723). These superior properties indicate that the GS/ZNR hybrids are promising field cathodes in FE applications.

Zinc oxide/zinc tungstate (ZnO/ZnWO 4 ) nanorods were synthesized as composite nanostructure on the tungsten/glass substrates by thermal oxidation technique for field emission cathodes. The ZnWO 4 wolframite structure in the ZnO film formed the ZnO/ZnWO 4 composite nanostructure, as indicated by the XRD patterns and Raman spectrum. An ohmic contact was transformed to a Schottky contact between a silver electrode and the ZnO/ZnWO 4 composite nanorods from I–V measurement given that the work function of the ZnO/ZnWO 4 composite nanorods was lower than that of ZnO nanorods. The field emission properties of the ZnO/ZnWO 4 composite nanorods includes a turn-on electric field (E on ) of 2.1 V/μm and a threshold electric field (E th ) of 2.9 V/μm, both much lower than that found in ZnO nanorods without ZnWO 4 nanostructures. The novel ZnO/ZnWO 4 composite nanorod shows excellent potential for application in field emission cathodes and related devices.

We have developed a free lithography technique for hydrogen sensors using a cracked carbon nanotube/nickel (CNT/Ni) film with horizontally aligned CNT (HA-CNT). Cracks were induced on CNT/Ni film by simple hydrogen absorption and desorption processes to enhance sensor response using heat treatment. Gas sensing measurements taken with various concentrations (200–16,000 ppm) of hydrogen at room temperature revealed that the sensors based on cracks in CNT/Ni film exhibit promising results for response, response time, and recovery time. Compared to CNT/Ni sensors fabricated without heat treatment, the hydrogen sensors fabricated at 350 °C on cracked CNT/Ni film with HA-CNT exhibited a much more response (14.1% vs. 0.6%) and a faster response time (422 s vs. 1095 s) at 200 ppm H2 gas. The heat treatment method used to form cracks in the HA-CNT is relatively simple and effectively improved the response of CNT/Ni hydrogen sensors.

A horizontally-aligned carbon nanotube (HACNT) field emission cathode was coated with a metallic glass thin film (MGTF) to improve the stability of the field emission properties. HACNT field emission cathodes have previously been fabricated on glass substrates using composite plating and crack-formation techniques. A carbon nanotubes/nickel (CNTs/Ni) composite film is deposited onto a glass substrate at 80 °C by the composite plating technique alone. Cracks are then formed in the CNT/Ni composite film during 30 min heating at 300 °C, and HACNTs are exposed in the cracks. The field emission properties of the HACNT field emission cathode show a low turn-on electric field Eon of about 2.3 V/μm, a low threshold electric field Eth of about 4.7 V/μm at an emission current density of 1 mA/cm2, and a stability time of 78 h. The degradation of the HACNT field emission cathode is prevented by using a MGTF-coating technique and superior long-term stability (i.e. >125 h, with 5 nm MGTF; >270 h, with 10 nm MGTF) for the MGTF/HACNT field emission cathode is achieved.

A new PSG doping process was developed using a sol-gel method with phosphorus pentoxide (P2O5) powder combined with a screen-printing technique for the fabrication of electrodes. This process was applied in silicon nanowire (SiNW) arrays based solar cells. The PSG-doped SiNW arrays were used as both the anti-reflectance layer and the n+ emitter for the solar cells. The morphology and photoelectric characteristics of the SiNW array solar cells were measured by a scanning electron microscope (SEM), a UV/VIS/NIR spectrophotometer, a quantum efficiency measurement system and a solar cell simulator. It was found that the reflectivity (Rλ), internal quantum efficiency (IQE), series resistance (Rs) and power conversion efficiency (PCE) were influenced by the aspect ratio and the density of the PSG-doped SiNW arrays. Results indicate that there is a competition phenomenon between the aspect ratio and the density. It was observed that certain aspect ratio (∼5.15) with appropriate density (∼34.5%) of PSG-doped straight-aligned SiNW arrays possessed better solar cell (∼10.15%) performance. The SiNW array solar cells showed potential for low cost and mass-production in commercial solar cells applications.

A leaf-like carbon nanotube/nickel (CNT/Ni) composite film modified with palladium nanoparticles (Pd NPs) was developed for hydrogen (H 2 ) gas sensing applications. A leaf-like CNT/Ni composite film was fabricated on glass by nanocomposite plating. A Pd/CNT/Ni film, which was treated by the sensitization and activation process, was then formed to improve the hydrogen sensing properties. The H 2 gas sensing properties of the Pd/CNT/Ni were found to have a much higher response (7.3%) and faster response time (312 s) at 200 ppm H 2 gas than those prepared without Pd NPs modified (0.7%, 1092 s). The modified Pd/CNT/Ni composite film sensor possessed good sensing properties and has potential for mass production in flexible sensing devices.

A simple method using a combination of nanocomposite plating and firing techniques for the production of horizontally aligned carbon nanotube (HACNT)-based hydrogen gas sensors is presented. This low temperature (100 °C) firing process generates cracks in which HACNTs are formed. Hydrogen sensing characteristics are measured in various gas concentrations from 200 ppm to 16,000 ppm at room temperature. The HACNT-based hydrogen gas sensor performs with low noise, short response time, and fast recovery time. It is found that the HACNT-based sensors have a much better sensitivity response (approximately 5 times) than the original CNT/Ni film sensors which use a nanocomposite plating technique only. The Raman spectra of the HACNT-based sensors show that more defects and oxidation were generated on the HACNTs after the firing process. The firing process decreases the oxygen vacancies of CNTs to enhance the sensitivity response of HACNT-based sensors. In addition HACNT-based sensors are relatively simple, cost-effective and mass-producible.

Gas ionization sensors based on the field emission properties of the carbon nanotube/nickel (CNT/Ni) field emitters were first developed in this work. It is found that the breakdown electric field (E(b)) slightly decreases from 2.2 V/microm to 1.9 V/microm as the pressure of H2 gas increases from 0.5 Torr to 100 Torr. On the contrary, E(b) obviously increases from 2.9 V/microm to 6.5 V/microm as O2 gas pressure increases from 0.5 Torr to 100 Torr. This may be explained by the depression of the electron emission that caused by the adsorption of the O2 gas on the CNT emitters. The Raman spectra of the CNT/Ni emitters also show that more defects were generated on the CNTs after O2 gas sensing. The Joule heating effect under high current density as performing H2 sensing was also observed. These effects may contribute the pressure dependence on the breakdown electric field of the CNT/Ni gas ionization sensors.

Arrays of nanocrystalline diamond (NCD) stripes were fabricated by plasma etching of a NCD film. Electron field emission (EFE) of NCD arrays with 100-μm-wide stripes separated by different spacings was analyzed. The NCD arrays had higher EFE efficacy than the non-patterned blanket NCD film. The turn-on electric field ( E on ) decreased from 5.4 V/μm -1 for the blanket NCD film to 4.2, 4.4 and 4.7 V/μm − 1 for the NCD arrays with 100, 500 and 1000 μm of spacing, respectively. Both the effective emitting area and the field enhancement factor for the NCD emitters were increased by patterning. The enhanced EFE from arrayed NCD stripes was possibly attributed to the edge effect and reduction of electrostatic screening.

Carbon nanotubes (CNTs) have high aspect ratio and have great potential to be applied as the field emission cathode because of its large field enhancement factor. In this work, a high performance carbon nanotube field emission cathode (CNTFC) was fabricated by using a composite plating method. The CNTs were purified by acid solutions and then dispersed in electrobath with nickel ions at temperatures of 60, 70, or 80 degrees C for the electroless plating process on glass substrate. The resulting CNT-Ni composite film has strong adhesion on the glass substrate. The degree of graphitization and the microstructure of the CNTFCs were studied by Raman spectroscopy and scanning electron microscopy. The field emission properties of the CNTFCs show a low turn-on electric field E(on) of about 1.2 V/microm, and a low threshold electric field E(th) of about 1.9 V/microm. Such a composite plating method could be applied to the fabrication of large area CNT field-emission displays.

We present a smooth approximation for the generalized Fischer–Burmeister function where the 2-norm in the FB function is relaxed to a general p -norm ( p > 1 ), and establish some favorable properties for it — for example, the Jacobian consistency. With the smoothing function, we transform the mixed complementarity problem (MCP) into solving a sequence of smooth system of equations, and then trace a smooth path generated by the smoothing algorithm proposed by Chen (2000) [28] to the solution set. In particular, we investigate the influence of p on the numerical performance of the algorithm by solving all MCPLIP test problems, and conclude that the smoothing algorithm with p ∈ ( 1 , 2 ] has better numerical performance than the one with p > 2 .

Several Human-Machine/Computer Interfaces (HMI/HCI) had been developed in recent years. Some designs were specifically made for people with disabilities such as injured-vertebra, apoplexy or poliomyelitis, Amyotrophic Lateral Sclerosis (ALS), and Motor Neuron Disease, (MND). In this paper, we proposed an eye-movement tracking system. Based on Electro-Oculography (EOG) technology we detected the signal with different directions in eye-movements and then analyzed to understand what they represented about (e.g. horizontal direction or vertical direction). We converted the analog signal to digital signal and then used as the control signals for Human-Computer Interface (HCI). In order to make the system ''robust'', several applications with EOG-based HCI had been designed. Our preliminary results revealed more than 90% accuracy rate for examining the eye-movement that may become a new useful human-machine user interface in the near future.

A novel composite plating method has been developed for the fabrication of carbon nanotube/Ni (CNT/Ni) field emission cathode. The field emission properties of the initial CNT/Ni field emitter show a low turn-on electric field E on of about 1.1 V/μm with an emission current density of 1 μA/cm 2 , and a low threshold electric field E th of about 1.7 V/μm with an emission current density of 1 mA/cm 2 . After performing a stability test with a high emission current density in high vacuum, the corresponding microstructure and the degree of graphitization of the CNT/Ni field emitter were measured by using scanning electron microscopy and Raman spectroscopy. We found that the degree of graphitization slowly decreases with the duration time t FE of the stability test, the size of small rod-like CNT/Ni composite structures in the film increases with t FE , and obvious cracks appear in the film as t FE is larger than 60 h. The degradation of the field emission properties may be explained by the Joule heating effect on the CNT/Ni field emitter under high emission current density.

Aims and objectives This study aimed to examine the relationship between work stress and depression; and investigate the mediating effect of occupational burnout among nurses in paediatric intensive care units. Background The relationships among work stress, occupational burnout and depression level have been explored, neither regarding occupational burnout as the mediating role that causes work stress to induce depression nor considering the paediatric intensive care unit context. Design A cross-sectional correlational design was conducted. Methods One hundred and forty-four female paediatric intensive care unit nurses from seven teaching hospitals in southern Taiwan were recruited as the participants. Data were collected by structured questionnaires including individual demographics, the Nurse Stress Checklist, the Occupational Burnout Inventory and the Taiwan Depression Questionnaire. Results The results indicated that after controlling for individual demographic variables, the correlations of work stress with occupational burnout, as well as work stress and occupational burnout with depression level were all positive. Furthermore, occupational burnout may exert a partial mediating effect on the relationship between work stress and depression level. Conclusion This study provides information about work stress, occupational burnout and depression level, and their correlations, as well as the mediating role of occupational burnout among paediatric intensive care unit nurses. Relevance to clinical practice It suggests government departments and hospital administrators when formulating interventions to prevent work stress and occupational burnout. These interventions can subsequently prevent episodes of depression in paediatric intensive care unit nurses, thereby providing patients with a safe and high-quality nursing environment.

This paper reports an organic–inorganic hybrid solar cell with a hierarchical surface composed of high density silicon nanoholes and micro-desert textures. High-efficiency organic–inorganic hybrid solar cell Si/PEDOT–PSS with a hierarchical surface, showing a power conversion efficiency of 12%. The structure provides excellent light absorption over 97% for the spectral range of 300 to 1100 nm with a thickness of 60 μm due to internal multiple reflections caused by subwavelength features of high density silicon nanoholes and micro-desert textures. In addition, from the angle of incidence (AOI) observed, even at the large angle of 75°, the reflectance value still exhibits less than 1%. With the advantage of very thin silicon material and inexpensive processing, hybrid silicon/polymer solar cells are promising for various applications and thus could be an economically feasible alternative energy solution in the future.

We fabricate Silicon nanowire (SiNW) arrays for solar-cell applications on 6-inch wafers employing metal-assisted chemical etching (MacEtch). It can reduce cost and energy consumption. However it is difficult to make uniform SiNW arrays on large size wafer. Here we demonstrate a simple method to achieve a uniform SiNW on 6 inch wafers. Moreover, optical properties and surface morphologies of 6 inch N-type pyramid/SiNW arrays and 6 inch P-type as-cut/SiNW arrays are investigated. Reflectance indicates the extensive light-trapping effect by the SiNW arrays. Thus, the improved MacEtch method is promising for future commercial mass production on large size wafers.

Si nanohole and nanowire/organic polymer solar cell is fabricated by low temperature and simple spin-coating method. The results show that the nanohole device performance is better than that of nanowire device. The Si nanohole device has higher external quantum efficiency in all wavelengths. The reason for the enhancement is analyzed from optical reflectance and the observation between Si nanohole and PEDOT:PSS interface. With nanohole structure, the short-circuit current density is increased from 22.1 to 26.9 mA/cm2 (22% increase), and the power conversion efficiency is enhanced from 7.4% to 8.0%. Nanohole structure is promising for high-efficiency Si/organic polymer solar cell.

With the development of information technology and medical technology, medical information has been developed from traditional paper records into electronic medical records, which have now been widely applied. The new-style medical information exchange system "personal health records (PHR)" is gradually developed. PHR is a kind of health records maintained and recorded by individuals. An ideal personal health record could integrate personal medical information from different sources and provide complete and correct personal health and medical summary through the Internet or portable media under the requirements of security and privacy. A lot of personal health records are being utilized. The patient-centered PHR information exchange system allows the public autonomously maintain and manage personal health records. Such management is convenient for storing, accessing, and sharing personal medical records. With the emergence of Cloud computing, PHR service has been transferred to storing data into Cloud servers that the resources could be flexibly utilized and the operation cost can be reduced. Nevertheless, patients would face privacy problem when storing PHR data into Cloud. Besides, it requires a secure protection scheme to encrypt the medical records of each patient for storing PHR into Cloud server. In the encryption process, it would be a challenge to achieve accurately accessing to medical records and corresponding to flexibility and efficiency. A new PHR access control scheme under Cloud computing environments is proposed in this study. With Lagrange interpolation polynomial to establish a secure and effective PHR information access scheme, it allows to accurately access to PHR with security and is suitable for enormous multi-users. Moreover, this scheme also dynamically supports multi-users in Cloud computing environments with personal privacy and offers legal authorities to access to PHR. From security and effectiveness analyses, the proposed PHR access scheme in Cloud computing environments is proven flexible and secure and could effectively correspond to real-time appending and deleting user access authorization and appending and revising PHR records.

Thin-film crystalline photovoltaic (PV) cell is a trend for future PV with its potential to achieve low cost and high efficiency. Concerning material utilization efficiency, we propose a method with a fast manufacturing method of thin crystalline Si by chemical solution. To obtain the highest efficiency of material utilization, experiments with different H 2 O 2 /HF ratio are conducted, where related mechanisms are discussed. Moreover, large-area (87.7 mm2) thin film transferred to glass is demonstrated, and with embedded nanohole structure, lowest optical reflectance of 0.26% is measured. These characteristics show that the fabricated thin film has potential for large-area crystalline thin film PV.

Protocols of user authentication are able to ensure the security of data transmission and usersi¦ communication over insecure networks. Among various authenticated mechanisms run currently, the password-based user authentication, because of its efficiency, is the most widely employed in different areas, such as computer networks, wireless networks, remote login, operation systems, and database management systems. Even as password is endowed with the property of simple and human memorable, for which causes such an attack of brute force, for example, the previous works often suffer off-line password guessing attack. Therefore, an ameliorative password-based authentication scheme is proposed in this paper, achieving to resist off-line password guessing attacks, replay attacks, on-line password guessing attacks, and ID-theft attacks. In light of security, the proposed scheme is provided with good practicability, even over insecure network.