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Abstract: First responders are generally a high-risk group, repeatedly exposed to traumatic and distressing scenes and events on their daily duties. Identification of detailed features and recurring patterns of intrusive visual imagery for first responders with posttraumatic stress disorder (PTSD) can uncover the psychological difficulties, defenses, and further adjustment issues of occupational groups exposed to repetitive trauma. To this end, 20 Rorschach protocols for Korean first responders with PTSD symptoms were collected and analyzed. The analysis of the Rorschach records was twofold. First, the structural features of the Rorschach responses, including R and the Trauma Content Index, were examined quantitatively. Second, the detailed features of the morbid content, such as thematic classification, trauma memory responses, and emotional reactions, were qualitatively reviewed. Both analyses identified a biphasic pattern between constricted and flooded responses, showing the participants’ unsuccessful endeavors to defend against intrusive trauma-related imagery, which resulted in significant disorganization in thought and affect.

Exopolysaccharide (EPS)-producing

Chlorin E6 (Ce6)-incorporated nanophotosensitizers were fabricated for application in photodynamic therapy (PDT) of oral cancer cells. For this purpose, chitosan oligosaccharide (COS) was conjugated with hydrophobic and reactive oxygen species (ROS)-sensitive moieties, such as phenyl boronic acid pinacol ester (PBAP) via a thioketal linker (COSthPBAP). ThdCOOH was conjugated with PBAP to produce ThdCOOH-PBAP conjugates and then attached to amine groups of COS to produce a COSthPBAP copolymer. Ce6-incorporated nanophotosensitizers using the COSthPBAP copolymer were fabricated through the nanoprecipitation and dialysis methods. The Ce6-incorporated COSthPBAP nanophotosensitizers had a small diameter of less than 200 nm with a mono-modal distribution pattern. However, it became a multimodal and/or irregular distribution pattern when H2O2 was added. In a morphological observation using TEM, the nanophotosensitizers were disintegrated by the addition of H2O2, indicating that the COSthPBAP nanophotosensitizers had ROS sensitivity. In addition, the Ce6 release rate from the COSthPBAP nanophotosensitizers accelerated in the presence of H2O2. The SO generation was also higher in the nanophotosensitizers than in the free Ce6. Furthermore, the COSthPBAP nanophotosensitizers showed a higher intracellular Ce6 uptake ratio and ROS generation in all types of oral cancer cells. They efficiently inhibited the viability of oral cancer cells under light irradiation, but they did not significantly affect the viability of either normal cells or cancer cells in the absence of light irradiation. The COSthPBAP nanophotosensitizers showed a tumor-specific delivery capacity and fluorescence imaging of KB tumors in an in vivo animal tumor imaging study. We suggest that COSthPBAP nanophotosensitizers are promising candidates for the imaging and treatment of oral cancers.

Recent studies suggest that the nonlinear transport properties in Weyl semimetal may be a measurable consequence of its chiral anomaly. Nonlinear responses in transport are estimated to be substantial, because in real materials such as TaAs or Bi$_{1-x}$Sb$_x$, the Fermi level resides near the Weyl nodes where the chiral charge pumping is said to diverge. However, this work presents semiclassical Boltzmann analysis that indicates that the chiral charge pumping is non-divergent even at the zero-temperature limit. We demonstrate that the divergence in common semiclassical calculation scheme is not a problem of the scheme itself, but occurs because a commonly-used approximation of the change in particle number breaks down near the Weyl nodes. Our result suggests the possibility that the nonlinear properties in WSMs can be overestimated, and provides the validity condition for the conventional approximation. We also show the distinct Fermi level dependencies of the chiral magnetic effect and the negative longitudinal magnetoresistance, as a consequence of non-diverging chiral charge pumping., 8 pages, 3 figures, Physical Review B accepted version

이 연구는 동의 과정에 주목하여 북한이탈주민의 취약성을 분석하고, 관련 현안을 발굴한 뒤 그에 따른 구체적 보호조치를 모색하고자 하였다. 문헌분석, 북한이탈주민 심층면담, 전문가 자문 등을 통하여 연구한 결과는 다음과 같다. 첫째, 북한이탈주민은 북한에서의 사회화 및 일상경험, 제3국에서의 도피생활, 입국 이후의 정착 과정 등을 겪으면서 인지적/의사소통적 취약성, 사회적 취약성, 문화적 취약성, 제도적 취약성, 의학적 취약성, 경제적 취약성, 신변안전의 취약성을 지니는 것으로 나타난다. 동의 과정에서 드러나는 가장 심각한 취약성은 인지적/의사소통적 취약성이며 그 다음으로는 사회적 취약성이 작용한다. 둘째, 동의 과정에서의 북한이탈주민 취약성 보호 현안은 총 3가지가 도출되었다. 가장 시급한 현안은 동의서 이해의 어려움이며, 이는 언어적/의사소통적 취약성에 기인한다. 의무/권리 의식이 부족/결여, 사회적 취약성에 기인한 소극적 자기표현점 또한 주요 의제로 나타났다. 셋째, 현안의 해결방안으로, 연구자는 동의서/설명문 작성 및 구두설명 시 북한이탈주민 대상자의 실질적 모국어에 맞추어 쉬운 단어, 짧은 문장, 보조언어(중국어) 등을 사용할 필요가 있다. 또한 국가생명윤리심의위원회 차원에서 개별 기관위원회와 연구진을 위해 심층 교육 및 자문을 제공하는 온라인 통합 플랫폼을 마련하는 구조적(법제적) 방안도 생각해볼 수 있다.

To construct a system for the effective hydrogen production from food waste, the conditions of anaerobic digestion and biogas reforming have been investigated and optimized. The type of agitator and reactor shape affect the performance of anaerobic digestion reactors. Reactors with a cubical shape and hydrofoil agitator exhibit high performance due to the enhanced axial flow and turbulence as confirmed by simulation of computational fluid dynamics. The stability of an optimized anaerobic digestion reactor has been tested for 60 days. As a result, 84 L of biogas is produced from 1 kg of food waste. Reaction conditions, such as reaction temperature and steam/methane ratio, affect the biogas steam reforming reaction. The reactant conversions, product yields, and hydrogen production are influenced by reaction conditions. The optimized reaction conditions include a reaction temperature of 700 °C and H2O/CH4 ratio of 1.0. Under these conditions, hydrogen can be produced via steam reforming of biogas generated from a two-stage anaerobic digestion reactor for 25 h without significant deactivation and fluctuation.

Objectives:Bioethanol is known as an important energy source that comes from plants, uses existing energy infrastructure without additional investment, and emits a low concentration of pollutants during combustion as eco-friendly renewable energy. Microalgae is reported as an effective material for producing bioethanol because of rapid biomass growth and relatively easy pretreatment steps. The objectives of this study are 1) to introduce general information of bioethanol production, 2) to show various processes for bioethanol production from microalgae, and 3) to provide an economic perspective of bioethanol. Methods:Recent published peer-reviewed papers were collected and analyzed. The contents follow the order: 1) introduction, 2) general information about microalgae for bioethanol production, 3) bioethanol producing processes, 4) economic feasibility, and 5) conclusion.Results and Discussion:The selection of the microalgae species and growing method are important to obtain high yield bioethanol. Physical, chemical, biological pretreatment was introduced. Also, comparison of the bioethanol producing processes was provided. Conclusions:Bioethanol production from microalgae is a promising energy source because microalgae have lots of advantages as effective biomass such as rapid growth, high polysaccharide contents, and easy preparing step for bioethanol production. However, it has some limitations that need to overcome. Algae growing method, pretreatment technology, and fermentation steps still require advanced technology, which can improve economic feasibility.

Objectives:An experimental study was conducted to investigate the membrane filtration characteristics of mixed liquor in methanogenic reactor to extend solid retention time (SRT) in food waste anaerobic digestion system.Methods:On the basis of the particle size distribution (0.5~700 µm) of the methanogenic mixed liquor, three grade membranes (MF, UF, NF) were tested in a stirred cell filtration and a plate type module. Furthermore foulants of membrane, especially UF, was investigated by SEM-EDS, FTIR, SEC.Results and Discussion:As a result UF membrane was selected for stable filtration of the liquor in terms of flux (2.51 L/m2･h･bar) and the flux recovery (100%) as well as filtration resistance (Total 7.15.E+13 m-1). Average flux was 18 L/m2･h･bar for the selected UF membrane in cross flow filtration using a flat plate module. The filtration results showed that membrane fouling was caused by gel and cake layer formed on the membrane surface and 90% of the initial flux could be recovered by physical washing. It was identified that major fouling causing materials were byproducts of carbohydrate and protein decomposition, and small amount of inorganic substance detected on the membrane surface were salt and struvite like materials.Conclusions:Based on the membrane filtration characteristics analyzed from the study, the UF membrane coupled anaerobic digestion is feasible to be applied as a novel food waste treatment system for SRT extension of the methanogenic reactor.

Objectives:An experimental study was conducted to investigate the membrane filtration characteristics of mixed liquor in methanogenic reactor to extend solid retention time (SRT) in food waste anaerobic digestion system. Methods:On the basis of the particle size distribution (0.5~700 µm) of the methanogenic mixed liquor, three grade membranes (MF, UF, NF) were tested in a stirred cell filtration and a plate type module. Furthermore foulants of membrane, especially UF, was investigated by SEM-EDS, FTIR, SEC. Results and Discussion:As a result UF membrane was selected for stable filtration of the liquor in terms of flux (2.51 L/m2･h･bar) and the flux recovery (100%) as well as filtration resistance (Total 7.15.E+13 m-1). Average flux was 18 L/m2･h･bar for the selected UF membrane in cross flow filtration using a flat plate module. The filtration results showed that membrane fouling was caused by gel and cake layer formed on the membrane surface and 90% of the initial flux could be recovered by physical washing. It was identified that major fouling causing materials were byproducts of carbohydrate and protein decomposition, and small amount of inorganic substance detected on the membrane surface were salt and struvite like materials. Conclusions:Based on the membrane filtration characteristics analyzed from the study, the UF membrane coupled anaerobic digestion is feasible to be applied as a novel food waste treatment system for SRT extension of the methanogenic reactor.

Various agents, including ethylenediaminetetraacetic acid, oxalic acid, citric acid, and HCl, were applied to remove heavy metals from raw paper incineration ash and render the ash recyclable. Among these prepared agent solutions, ethylenediaminetetraacetic acid showed the highest efficiency for Pb removal, while oxalic acid showed the highest efficiencies for Cu, Cd, and As removal. Additionally, three modes of an advanced removal method, which involved the use of both ethylenediaminetetraacetic acid and oxalic acid, were considered for use at the end of the rendering process. Among these three modes of the advanced removal method, that which involved the simultaneous use of ethylenediaminetetraacetic acid and oxalic acid, i.e., a mixture of both solutions, showed the best heavy metal removal efficiencies. In detail, 11.9% of Cd, 10% of Hg, 28.42% of As, 31.29% of Cu, and 49.19% of Pb were removed when this method was used. Furthermore, the application of these three modes of the advanced removal method resulted in a decrease in the amounts of heavy metals eluted and brought about an increase in the CaO content of the treated incineration ash, while decreasing its Cl content. These combined results enhanced the solidification effect of the treated incineration ash. Thus, it was confirmed that the advanced removal method is a promising strategy by which recyclable paper incineration ash can be obtained.

In this study, hydrogen production using food waste was optimized by investigating the effect of agitator types in anaerobic digestion reactors and catalysts for biogas reforming. The applied agitators were pitched blade and hydrofoil, and their effect on homogeneity was estimated using computational fluid dynamics. Reactors with different agitators were operated for 60 days for biogas production. Increased biogas production was observed in the reactor equipped with a hydrofoil agitator owing to its high homogeneity. In addition, Ni-CeZrO

대학생 우울성향 집단을 대상으로 미래 사고 과제(future thinking task)로 측정한 긍정적 미래 사고의 부족이 부정적 미래 사고, 우울 및 무망감과는 독립적으로 자살사고에 고유한 영향을 미칠 것이라는 가설을 검증하였다. 또한 긍정적 미래 사고의 내용, 구체성 및 범주의 다양성이 자살사고와 어떠한 관련을 맺는지 탐색하고자 하였다. 우울성향 대학생 64명을 대상으로 사전에 우울척도인 CES-D, 벡 절망 척도(K-BHS)와 자살사고 척도(SIQ)에 응답하게 했다. 미래 사고 과제를 실시한 후 본인이 보고한 미래의 긍정적 경험 중 3가지를 골라 구체적으로 적도록 지시하였다. 긍정적 미래 사고의 정도는 부정적 미래 사고와 유의한 정적 상관을 나타냈지만, 우울, 무망감 및 자살사고와는 유의한 부적 상관을 보였다. 또한, 긍정적 미래 사고는 부정적 미래 사고, 우울 및 무망감을 통제한 뒤에도 자살사고에 독립적으로 영향을 미쳤다. 긍정적 미래 사고의 내용 중 대인관계 영역은 자살사고와 유의한 부적 상관을, 개인내적 영역은 유의한 정적 상관을 나타냈고, 긍정적 미래 사고의 구체성은 자살사고와 유의한 정적 상관을 나타냈지만 우울 정도를 통제한 뒤에는 유의하지 않았다. 본 연구의 이론적 · 임상적 함의와 제한점을 논의하였다.