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Abstract Cooling radiant ceiling panel (CRCP) systems have been increasingly applied to modern buildings, owing to high thermal comfort, energy-saving potential, and integration with building design. Currently, the cooling capacity of CRCP is generally evaluated for the closed-type CRCP, wherein the overall ceiling surface is covered with ceiling panels. However, there have been few previous studies on the evaluation of the cooling capacity for open-type CRCP, which are installed with openings (void areas) between adjacent ceiling panels. This study was conducted to verify the hypothesis that the open-type CRCP can enhance cooling capacity by utilizing the cooled plenum air moving through the opening. If the plenum air is cooled by the upper surface of ceiling panels and descends to the conditioned space, it can contribute to increasing the convective heat transfer and cooling capacity. A simulation model for open-type CRCP was developed and validated against the mock-up experiment. Using the simulation model, the cooling capacity of the open-type CRCP was evaluated with respect to the opening area and panel layout. The results showed that the open-type CRCP could provide 54–80% (average 64%) higher nominal cooling capacity than conventional closed-type CRCP. The enhanced cooling capacity may lead to reduction in construction costs and energy consumption, because panel installation area could be reduced and the water temperature can be increased to provide the required cooling capacity. The results of this study would be able to offer fundamental data about cooling capacity of open-type CRCP. Highlights • The cooling capacity of open-type CRCPs was evaluated with a numerical method. • The developed simulation model of open-type CRCPs was validated through mock-up experiments. • The relation between the cooling capacity and design parameters of open-type CRCPs was analyzed. • Open-type CRCPs provided 54–80% higher nominal cooling capacity than closed-type CRCPs. • More cooling capacity can be obtained with a larger opening area and a distributed panel layout. [ABSTRACT FROM AUTHOR]

With a layered crystal structure and good Li + storage performance, vanadium pentoxide (V 2 O 5 ) is potentially a high-energy and cost-effective cathode material for Li-ion batteries (LiBs). Networks of two-dimensional V 2 O 5 nanosheets (2D V 2 O 5 NS), with large interlayer distance, are ideal for enhancing the Li + diffusion kinetics and thus for building high power LiBs. However, the lack of a simple, scalable and environmentally friendly route to nanosheet production still hinders the development of V 2 O 5 applications. Here we demonstrate, liquid-phase exfoliation (LPE) of commercial V 2 O 5 powder in environmental friendly solvents (water and ethanol) to achieve large quantities of 2D V 2 O 5 NS dispersions. The V 2 O 5 NS are of high-quality whose interlayer spacing can be well manipulated, ranging from 4.4Å to 11.5 Å in ethanol and water (forming NS xerogel), respectively. Ultrasonic aerosol printing of V 2 O 5 NS xerogel/single-wall carbon nanotube (SWCNT) blended dispersions resulted in large-area, flexible, and binder-free hybrid electrodes, which showcase a high discharge capacity of 370 mA h g −1 at 0.05 C, high energy density (555 W h kg −1 ) and power density (2175 W kg −1 ), etc . These properties can be attributed to the synergistic effects between the expanded hydrated NS and the conductive SWCNT matrix; the latter improves the reversible phase transition reactions of the NS, enhances the ion diffusion kinetics, maintains the electrode's mechanical integrity and provides electron transport pathways. The Li + storage mechanism was investigated, suggesting the capacity was majorly contributed by the non-diffusion controlled process (pseudocapacitive). We believe the LPE/aerosol printing approach is environmentally green, general and scalable, and could be extended to other layered transitional metal oxides or dichalcogenides for fabrication of corresponding flexible, binder-free, conductive composites for energy storage systems. [ABSTRACT FROM AUTHOR]

Two-dimensional lithiated nanosheets usually show excellent electrochemical performance due to an increase in surface area and shorter diffusion paths. However, processing techniques, such as shear mixing or liquid phase exfoliation could induce phase changes or knock out some of the structural lithium (Li) ions, what in turn might result in poor electrochemical performance. Here different lithiated layered compounds mainly LiCoO 2 , LiMn 2 O 4 , and Li 5 Ti 4 O 12 were chemically exfoliated and investigated using electron energy loss spectroscopy (EELS) for their Li-K edge. Further analyses were carried out, looking at the oxygen (O) K edge with their respective transition metal core loss peak (Mn, Co and Ti) which revealed changes in the Energy loss near edge structures (ELNES) when compared to the unlithiated compounds. STEM-EELS analyses confirmed uneven distribution of lithium within the lithiated layered materials. In this work, EELS was used for the first time to detect and to probe the chemical environment of the lithium in liquid phase exfoliated material. [ABSTRACT FROM AUTHOR]

Transparent, conductive electrodes are important in many applications such as touch screens, displays and solar cells. Transparent energy storage systems will require materials that can simultaneously act as current collectors and active storage media. This is challenging as it means improving the energy storage capability of conducting materials while retaining transparency. Here, we have used aerosol-jet spraying strategy to prepare transparent supercapacitor electrodes from ruthenium oxide/poly(3,4-ethylenedioxythiophene): poly(styrene-4-sulfonate), (RuO 2 /PEDOT: PSS) hybrid thin films. These films combine excellent transparency with reasonably high conductivity (DC conductivity =279 S/cm) and excellent volumetric capacitance ( C V =190 F/cm 3 ). We demonstrate electrodes with historical high transparency of 93% which display an areal capacitance of C / A =1.2 mF/cm 2 , significantly higher than the rest reported electrodes with comparable transparency. We have assembled flexible, transparent, solid-state symmetric devices which exhibit T =80% and C / A =0.84 mF/cm 2 and are stable over 10,000 charge/discharge cycles. Asymmetric solid-state device with RuO 2 /PEDOT: PSS and PEDOT: PSS thin films as positive and negative electrodes, respectively, display an areal capacitances of 1.06 mF/cm 2 , a maximum power density ( P / A ) of 147 μW/cm 2 and an energy density ( E / A ) of 0.053 μWh/cm 2 . Furthermore, large area transparent solid-state supercapacitor device has been built. We believe the solution-processed transparent films could be easily scaled-up to meet the industrial demands. [ABSTRACT FROM AUTHOR]

Abstract: The existing assessment tools for the life cycle carbon dioxide (LCCO2) have certain limitations in that users have to directly enter quantities of materials after the construction document phase and they are likely to find it difficult to formulate an optimal strategy to reduce CO2 emissions. Therefore, Global Environmental Model/Management-21P (GEM-21P) was developed for establishing a responsive and accurate system for suggesting methods for high energy efficiency in the planning phase. The objective of this study is to identify the requisites for an LCCO2 assessment program that is based on the technical elements of GEM-21P and that can be used in the schematic design phase. The life cycle of a building is divided into four stages: material production, construction, operation, and dismantlement/disposal. Further, the technical elements of GEM-21P are examined for assessing CO2 emissions in each of the stages. On the basis of the examination results, we specify the requisites for a system that can assess, in the planning phase, the CO2 emitted from a building during its entire life. [Copyright &y& Elsevier]

Abstract: The objective of this study is to review how renovation policies are changing, and what political strategies have guided the promotion of housing renovation in the era of sustainability. In this study, renovation policies were compared and analyzed with emphasis on: (1) improvement of physical performance, (2) correspondence to the needs of the elderly, (3) improvement of energy efficiency and, (4) social cohesion and area revitalization. These are the political objectives of renovation that recently emerged as social issues in France, Germany, Denmark and Sweden among European countries that actively conduct renovations. First, Section reviews various social issues relating to existing housing and the objective of promoting renovation. Section describes changes in the role of renovation policies with a focus on changes in financial supports. Section performs a country-by-country cross-analysis of the objectives of renovation and the characteristics of policies promoting renovation. In Section , policies designed to promote housing renovation are classified into extension type, individual type, combined type and integrated type depending on the renovation objectives, and the characteristics are identified. In the summary, Section , suggestions for policies in the field are proposed. [Copyright &y& Elsevier]

Abstract: Submicron size polyethylene particles were prepared by a thermally induced phase separation process in a split-and-recombine type micromixer. Process parameters such as polyethylene concentration, ratio of nonsolvent to solvent, initial temperature of the nonsolvent and total flow rate play important roles in controlling particle size. The results show that spherical polyethylene particles were obtained with an average diameter ranging from 0.22μm to 0.52μm. The continuous flow micromixer system prevented coagulation, therefore the size of the prepared polyethylene particles can be predicted using the continuous flow micromixer system. [Copyright &y& Elsevier]

Abstract: Although Korea has as large a housing stock as other developed countries hold, it has striven to focus on growth-oriented policies by creating new housing units rather than maintaining or rehabilitating existing ones, which has resulted in a few efforts to develop policies to maintain and rehabilitate existing apartment houses. In early 1990, there was a huge construction of 2 million units of apartment housing in the areas around Seoul, such as Bundang and Ilsan. At this point of time when it has been nearly 20 years since the enormous construction, loan programs that enable the existing multiple dwellings to be maintained for sustainable usage are expected to receive much attention. In this study, the loan programs of New York City and Tokyo Metropolis to maintain multiple dwellings were analyzed as a model for Korean loan programs to support the maintenance of apartment houses, and based on the results of analysis, the directions of organizing the domestic loan programs to maintenance apartment houses were presented. The results are summarized as follows: First, along with the housing finance policies executed previously in New York and Tokyo, the Korean environment to maintenance apartment houses and policies for maintenance were examined. Then, the necessity for and imperfection of the policies of Korea to support the maintenance of apartment houses were identified. Second, the targets, benefits, qualification for application and conditions for benefits of the loan programs of New York and Tokyo for maintaining multiple dwellings were researched in order to find the basic framework of the loan programs. Last, based on the framework of the loan programs of New York and Tokyo, the directions of loan programs and measures to foster housing funds for maintaining apartment houses for Korea were proposed. [Copyright &y& Elsevier]

Abstract: Introduction: Endodontic-periodontal combined lesion is a clinical dilemma because making a differential diagnosis and deciding a prognosis are difficult. Methods: Twenty-six cases from 14 articles involving the successful management of endodontic-periodontal lesions with concurrent regenerative procedures were reviewed. This article also presents successful treatment of an endodontic-periodontal combined lesion involving a grade II mesial furcation of a maxillary molar with root canal treatment and multiple regenerative procedures. Results: A treatment algorithm is outlined for the application of the guided tissue regeneration (GTR) in managing endodontic-periodontal combined lesion. This treatment algorithm consists of 4 phases: (1) presurgical phase (determining periodontal/regenerative prognosis), (2) endodontic phase, (3) periodontal surgical phase, and (4) post-GTR reevaluation protocol. Conclusions: The proposed 4-phase treatment algorithm might provide a beneficial guideline in managing the endodontic-periodontal combined lesions. [Copyright &y& Elsevier]

The thermal performance of the building envelope is a major requirement for guaranteeing a comfortable and hygienic interior climate. The roof is a part of the building envelope which provides protection from thermal damage incurred by the sun. To improve this protection ability, the use of a ventilated roof can be considered, which has a ventilation layer known as a cavity, beneath the roof cover panel. The objective of this study is to evaluate the influence of such factors as cavity ventilation, the slope of the roof, intensity of solar radiation, the size and shape of the cavity, and panel profiles, by investigating airflow and temperature distribution in the cavity, in an effort to improve the cooling effect of ventilation in the cavity of the roof. In this study, the influence of these elements on airflow is studied. The evaluations are carried out by way of experiments. [Copyright &y& Elsevier]

Highlights: [•] Graphene nanosheets was manufactured using a simple modified version of a previously improved Hummers method. [•] The wrinkle-free graphene was easily manufactured from prepared graphene by post-process treatment. [•] Morphology-controlled graphene nanosheets showed excellent discharge performance. [•] Morphology-controlled graphene has the potential to be easily applied to graphene-wrapped composite. [ABSTRACT FROM AUTHOR]

Abstract: A total of 4330 food samples of which microbiological standard for Escherichia coli is negative in Korea were determined for the frequency of E. coli. Ninety six samples (2.2%) were positive for E. coli. Detection rate of E. coli varied significantly by food type and ranged from 0.3% to 10.9%. Seasoned raw meat (yukhoe) and cold bean-soup had the highest prevalence for E. coli (10.9%) followed by gimbap (5.2%), meat broth for cold noodle (2.9%) and sprout (2.1%). E. coli isolates (n=96) were investigated for their phenotypic and genotypic antimicrobial resistance patterns. Seventeen E. coli isolates (17.7%) were resistant to one or more antimicrobial agents tested. High rates of resistance to the following drugs were observed: tetracycline (15.6%), streptomycin (12.5%), ampicillin (10.4%), nalidixic acid (9.4%) and ticarcillin (9.4%). All ampicillin resistant isolates were screened for extended-spectrum β-lactamase (ESBL) production by the combination disk test. None of the E. coli isolates produced ESBLs. Seventeen out of 96 E. coli isolates which were resistant to at least one antibiotic were investigated by PCR for the presence of 3 classes of antimicrobial resistance genes (tetracycline, aminoglycosides and beta-lactams). The tetracycline resistance genes tetA and tetB were found in 7 and 5 isolates, respectively. The aminoglycoside resistance genes, strA/B, aphA1, aadA and aac(3)-IV were found in 9, 5, 2 and 2 isolates, respectively. The beta-lactam resistance gene, bla TEM was found in 7 isolates. Results of this study show that 13 E. coli isolates were multidrug resistant (to three or more antibiotics) and 12 isolates carried at least one antimicrobial resistance gene. These isolates can act as the reservoir for antimicrobial resistance genes and facilitate the dissemination of these genes to other pathogenic and commensal bacteria. Adequate intervention to reduce microbial contamination of these foods is strongly recommended. [Copyright &y& Elsevier]

Abstract: The ruthenium oxide nanoparticles dispersed on multi-wall carbon nanotubes (CNTs) were successfully synthesized via microwave-polyol process combined with forced hydrolysis without additional thermal oxidation or electrochemical oxidation treatment. The HRTEM, Raman spectra and TGA curve indicate that CNTs were uniformly coated with crystalline and partially hydrous RuO2·0.64H2O nanoparticles of 2nm diameter and the loading amount of ruthenium oxide in the composite could be controlled up to 70wt.%. The specific capacitance was 450Fg−1 of ruthenium oxide/CNT composite electrode with 70wt.% ruthenium oxide at the potential scan rate of 10mVs−1 and it decreased to 362Fg−1 by 18% at 500mVs−1. The specific capacitance of ruthenium oxide in the composite was 620Fg−1 of ruthenium oxide at 10mVs−1. The ruthenium oxide nanoparticles in ruthenium oxide/CNT nanocomposite electrode had a high ratio of outer charge to total charge of 0.81, which confirmed its high-rate capability of the composite through the preparation of the nano-sized ruthenium oxide particles on the external surface of CNTs. [ABSTRACT FROM AUTHOR]

Abstract: Since human papillomavirus (HPV) E6 and E7 are promising tumor antigens, we engineered E6 and E7 antigens to generate an optimal HPV DNA vaccine by codon optimization (Co), fusion of E6 and E7, addition of a tissue plasminogen activator (tpa) signal sequence, addition of CD40 ligand (CD40L) or Fms-like tyrosine kinase-3 ligand (Flt3L). The resulting constructs were investigated in terms of their antitumor activity as well as induction of HPV-specific CD8+ T cell responses. When E6Co and E7Co were fused (E67Co), CD8+ T cell responses specific for E6 or E7 antigen decreased, but the preventive antitumor effect rather improved, demonstrating the importance of broad immunity. Interestingly, Flt3L-fused HPV DNA vaccine exhibited stronger E6- and E7-specific CD8+ T cell responses as well as therapeutic antitumor effect than that of CD40L linked HPV DNA vaccine. Finally, the optimal construct, tFE67Co, was generated by including tpa signal sequence, Flt3L, fusion of E6 and E7, and codon optimization, which induces 23 and 25 times stronger E6- and E7-specific CD8+ T cell responses than those of initial E67 fusion construct. In particular, inclusion of electroporation in intramuscular immunization of tFE67Co further enhances HPV-specific CD8+ T cell responses, leading to complete tumor regression in a therapeutic setting. Thus, our results provide valuable insight on effective HPV DNA vaccine design and suggest that tFE67Co delivered with electroporation may be a promising therapeutic HPV DNA vaccine against cervical cancer. [Copyright &y& Elsevier]

Understanding size-differential productivity characteristics of phytoplankton is important to evaluating climate-driven environmental changes in marine ecosystems. In this study, we derived the relative contribution of small phytoplankton (P small ; <5 μm) to the total primary production (TPP) and characterized their photosynthetic traits in comparison to large phytoplankton (P large) based on field-measured observations in the Chukchi Sea, 2012. The overall chlorophyll- a (51.8 ± 23.1%) and TPP contributions (52.3 ± 29.8%) of P small observed in this study were closely related to freshwater contents. In regards to nitrogen uptake, P small contributed 39.0% (S.D. = ± 28.4%) and 73.4% (S.D. = ± 50.1%) to the total nitrate uptake rate (TNP) and the total ammonium uptake rate (TAP), respectively, which is consistent with previous findings. Particulate and assimilated carbon/nitrogen (C/N) ratios were significantly (p < 0.01 and 0.05, respectively) lower in P small compared to P large , indicating their different natural capacities during growths. A significantly negative relationship was observed between the P small contribution and the TPP in the Chukchi Sea. These results imply that the more P small contribution in marine ecosystems could lead the less C sequestration from euphotic depths to deep ocean. In comparison to other regions, a more rapid decreasing TPP in the Chukchi Sea with increasing P small contribution is distinctively noticeable, which suggest that the Chukchi Sea ecosystem could be more vulnerable to an expected increase in P small contribution. • Contribution of small phytoplankton is closely related to freshwater content in the Chukchi Sea. • Significantly lower C/N ratios of small phytoplankton in comparison to large phytoplankton. • Strong negative relationship between small phytoplankton contribution and the total primary production. • Chukchi Sea ecosystem could be more vulnerable to increasing small phytoplankton. [ABSTRACT FROM AUTHOR]

For battery electrodes, measured capacity decays as charge/discharge current is increased. Such rate-performance is usually characterised via galvanostatic charge-discharge measurements, experiments which are very slow, limiting the speed at which rate experiments can be completed. This is particularly limiting during mechanistic studies where many rate measurements are needed. Building on work by Heubner at al., we demonstrate chronoamperometry (CA) as a fast method for measuring capacity-rate curves with hundreds of data points down to C-rates below 0.01C. While Heubner et al. reported equations to convert current transients to capacity vs. C-rate curves, we modify these equations to give capacity as a function of charge/discharge rate, R. We use these expressions to obtain simple equations which can accurately fit data for both capacity vs. C-rate and capacity vs. R at normal rates. Interestingly, at high-rates, the curves obtained from CA deviate from the normal behaviour showing a new, previously unobserved, decay feature. We associate this feature with the very early part of the current transient where electronic motion dominates the current. Using a simple model, we show that the dependence of the high-rate time constant on electrode thickness can be linked to electrode conductivity. Image 1 • Chronoamperometry can yield capacity-rate data much faster than standard methods. • The resultant data sets are much richer than standard capacity-rate data. • This work leads to an equation to fit capacity-rate data. [ABSTRACT FROM AUTHOR]