Development of a Simple Cell Lysis Method for Recombinant DNA Using Bacteriophage Lambda Lysis Genes

Boyun Jang,Yuna Jung,임동빈 한국미생물학회 2007 The journal of microbiology Vol.45 No.6

In this study, we describe the development of a simple and efficient method for cell lysis via the insertion of a bacteriophage lambda lysis gene cluster into the pET22b expression vector in the following order; the T7 promoter, a gene for a target protein intended for production, Sam7 and R. This insertion of R and Sam7 into pET22b exerted no detrimental effects on cellular growth or the production of a target protein. The induction of the T7 promoter did not in itself result in the autolysis of cells in culture but the harvested cells were readily broken by freezing and thawing. We compared the efficiency of the cell lysis technique by freezing and thawing to that observed with sonication, and determined that both methods completely disintegrated the cells and released proteins into the solution. With our modification of pET22b, the lysis of cells became quite simple, efficient, and reliable. This strategy may prove useful for a broad variety of applications, particularly in experiments requiring extensive cell breakage, including library screening and culture condition exploration, in addition to protein purification.

Formation of SiO_x shell on Si nanoparticles and its effects on electrochemical properties as a Li-ion battery's anode

Jang, Boyun,Koo, Jeongboon,Choi, Sunho,Kim, Joonsoo Elsevier 2018 Materials chemistry and physics Vol.215 No.-

<P><B>Abstract</B></P> <P>Crystalline Si core–amorphous SiO<SUB>x</SUB> shell nanoparticles were synthesized from SiCl<SUB>4</SUB> using an atmospheric microwave plasma process and their microstructures were investigated. It was found that the amorphous SiO<SUB>x</SUB> shell thickness was determined by varying the applied microwave power. The increase of applied power directly increased the length of the flame at the end of the plasma. Through observation of the microstructures with varying lengths of the flame, it was found that a highly crystalline Si phase was formed in the plasma and amorphous SiO<SUB>x</SUB> phase was formed in the flame. The longer flame resulted in the thicker SiO<SUB>x</SUB> shell around the Si core. The electrochemical properties of the varying SiO<SUB>x</SUB> shell thicknesses were also investigated in that the synthesized Si-SiO<SUB>x</SUB> nanoparticles were used as anode materials in a lithium-ion battery (LIB). Thin shells such as native oxide did not influence the electrochemical behaviour of the Si core, whilst some shells were too thick to allow Li-ions to react with the Si core. Using Si-SiO<SUB>x</SUB> nanoparticles with the optimum SiO<SUB>x</SUB>:Si ratio of 18:82, the following electrochemical properties were obtained: a first reversible capacity of 932 mAh/g, an initial columbic efficiency (ICE) of 52.5%, and a capacity retention of 83.7% at the 100<SUP>th</SUP> cycle.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Si nanoparticles with amorphous SiO<SUB>x</SUB> shells with various thicknesses are synthesized. </LI> <LI> The formation of SiO<SUB>x</SUB> shell and its effect on the Si nanoparticle is studied. </LI> <LI> The Si/SiO<SUB>x</SUB> ratios are varied by controlling flame length at the end of plasma. </LI> <LI> The relations between microstructures and electrochemical properties are analyzed. </LI> <LI> The Si-SiO<SUB>x</SUB> core-shell nanoparticle exhibits improved electrochemical performance. </LI> </UL> </P>

무선 네트워크 환경에서의 생성적 적대 신경망 기반 이 동성 예측 모델

장보윤 ( Boyun Jang ),( Syed Muhammad Raza ),김문성 ( Moonseong Kim ),추현승 ( Hyunseung Choo ) 한국정보처리학회 2020 한국정보처리학회 학술대회논문집 Vol.27 No.2

초저지연성을 요구하는 5G 네트워크 환경에서 기기의 핸드오버를 능동적으로 조절하는 시스템의 중요성이 대두되고 있으며, 특히 핸드오버 시 기기의 이동성을 예측하는 것은 필수적이다. 딥러닝 모델의 일종인 생성적 적대 신경망은 두 신경망 사이의 경쟁 구도를 이용하여 두 신경망의 성능을 모두 높이는 목적으로 사용된다. 본 논문에서는 주로 데이터 생성 모델로 사용되는 생성적 적대 신경망을 이용하여 무선 네트워크 환경에서 기기의 이동성을 예측하는 시스템을 개발하였다. 이를 통해 실제 모바일 네트워크 환경에 적용되었을 경우 핸드오버 속도를 높이도록 한다.

네트워크약리학을 이용한 소건중탕 활성성분 및 잠재적인 타겟 효능 예측

장보윤(Boyun Jang) 대한모유수유한의학회 2021 nipple confusion,breastfeeding consultation,IBCLC, Vol.2 No.1

Objectives: Due to the complex interactions among the multiple compounds of herbs or herbal formulations, there has been demand for systemic assessment for understanding the therapeutic effect of herbal formulations. To address this, here we introduced the network pharmacology based analysis to explore the potential targets and mechanisms of Sogunjung-tang. Methods: Active compounds of Sogunjung-tang were searched, and their target genes were collected from databases (TCMSP, STRING). Then network analysis was performed to visualize the interaction of herbs - compounds - target genes (Cytoscape). Gene Ontology and KEGG pathway analysis of target genes were also conducted to find out the associations with biological processes and pathways. Results: We identified 34 major active compounds and their 282 associated target genes of Sogunjung-tang. Gene Ontology analysis displayed the target gene enriched biological processes, which were oxidation-reduction and inflammatory response related groups. KEGG pathway analysis results also demonstrated the representative pathways including, antioxidant pathways, anti-inflammatory pathways, cancer pathways and neural pathways. Conclusions: Thus, these data provide a systematic way to understand and estimate the multiple targets and therapeutic actions of Sogunjung-tang.

Jageum-Jung, the herbal pharmaceuticals, inhibits the hepatic fibrogenesis as mediated with TGF-β1/smad signaling

송유림,Jang Mi Hee,Jang Boyun,Bae Su Jin,Bak Seon Been,Lee Sung Min,Yun Un-Jung,Lee Ju Hee,Park Sang Mi,Jung Dae Hwa,Sa Bok Suk,Song Jong Kuk,이은혜,김광연,Park Kwang-Il,김영우,김상찬 대한독성 유전단백체 학회 2022 Molecular & cellular toxicology Vol.18 No.2

Background Herbal prescriptions have various effects and their efficacy is potentiated by the use of combinations of medicinal herbs. Objective Jageum-Jung (JGJ) is a traditional oriental medical prescription composed of five herbs. It has been used for detoxifi cation, and as an anti-inflammatory and antitumor agent. However, the effect of JGJ on hepatic fibrogenesis is unclear. Results We investigated the role of JGJ in TGF-β1/smad signaling, which is implicated in fibrogenesis, and its hepatoprotective effect in CCl 4 -treated mice with liver fi brosis. Treatment of LX-2 cells with TGF-β induced expression of mediators (α-SMA, PAI-1, and MMP-2) of fibrogenesis and activation of proinflammatory cytokines (TNF-α, IL-1β, and IL-6). However, these were downregulated by pretreatment with JGJ. In mice, oral administration of JGJ prevented liver injury induced by CCl 4 , as indicated by decreases in the ALT and AST levels. Conclusions JGJ inhibits hepatic fibrogenesis and TGF-β1/Smad signaling.

Effects of mirror polishing brick surface on process yield of multi-wire slicing for thin single-crystalline silicon solar cells

Choi, Sunho,Jang, Boyun,Kim, Joonsoo,Song, Heeun,Baek, Taehyeon,Han, Moonhee Elsevier 2015 SOLAR ENERGY -PHOENIX ARIZONA THEN NEW YORK- Vol.122 No.-

<P><B>Abstract</B></P> <P>Thin silicon (Si) wafers with thickness of 100–140μm were obtained by using a multi-wire slicing process with a SiC slurry. We investigated the process yields of wafer slicing as well as physical/electrical properties of the sliced wafers with various thicknesses. As the wafer thickness decreases, the process yield abruptly decreased due to wafer breakage during the slicing process, and conventional polishing the brick surface was not enough to gain a considerable process yield. However, elimination of defects on the brick surface by mirror polishing resulted in an 83.1% enhancement of yield even for wafers with a thickness of 100μm. The number of wafers obtained was even higher than that of conventional 180μm-thick wafers (479 vs. 415 wafers in this research). Investigation of the microstructure of brick surfaces revealed that surface defects on bricks were main parameter to determine the yield of slicing process. Surface defects containing the micro-cracks introduced residual stress, which decreased the slicing process yield especially for thinner wafers. From measurements of physical and electrical properties, it was revealed that the relative total thickness variations (TTVs) and bowings increased and the characteristic fracture strength of sliced wafer and conversion efficiencies decreased as the wafer thickness decreased. For the wafer with thickness of 100μm, the relative TTV and bowing were 14.1% and 22.5mm, respectively. The conversion efficiency of a solar cell using this wafer was 17.6%, while that of a conventional Si solar cell using a 180μm-thick wafer was 18.4%.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Thin silicon wafers with thickness of 100–140μm were sliced by multi-wire slicing. </LI> <LI> Physical and electrical properties of thin Si wafers were investigated. </LI> <LI> Subsurface defects of the brick surface critically determined process yield in slicing Si wafers. </LI> </UL> </P>

Wire-electrical discharge machining on single crystalline Si brick as a new wafering process for photovoltaic applications

Lee Wooyoung,Jang Boyun 한국물리학회 2023 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.83 No.3

While electrical discharge machining (EDM) has been studied as a new wafering process for photovoltaic applications, there was a rare report of success to slice even a single wafer. Here, we have obtained (100)-oriented single crystalline silicon (Si) wafer with a dimension of 25×25×0.5 mm by electrical discharge. A tungsten (W) wire with a diameter of 500 μm and a Si brick with a dimension of 25×25×25 mm were used as electrodes. A specially designed power supply and pulse generator were applied to produce pulsed direct current (DC) with a frequency of several kHz. Typical waveforms of pulsed DC were investigated to achieve proper electrical discharge. Specifcally, the efects of applied voltage and pulse-on time on the process and microstructures of the sliced Si wafer were studied in detail. Applied voltage and pulse-on time determined the process performance such as slicing speed and material loss. They also determined the sliced Si wafer’s quality such as microstructural defects and roughness. In addition, pulse-on time critically determined the wire’s lifetime. Wire movement along the slicing channel and its servo control of z-motion are required to enhance the wafer’s quality as well as process performance.

Prediction of herb–drug interaction between hyperforin and sedative hypnotics (zolpidem, alprazolam, and midazolam) using physiologically-based pharmacokinetic modeling

Shin Anna,Jang Boyun,Cho Sunyoung,Kim Youngsoo,Park Min Soo,Park Kwang-Il,Kim Young Woo,Kim Choon Ok 대한독성 유전단백체 학회 2024 Molecular & cellular toxicology Vol.20 No.2

Background This study investigates the interactions between various doses of hyperforin, a key compound in St. John’s Wort, and sedative hypnotics such as zolpidem, alprazolam, and midazolam. Since St John’s Wort is known to be an inducer of cytochrome P450 (CYP) 3A4, co-administration with drugs metabolized by CYP3A4 has been contraindicated. Objective We studied the risks of combination use and the possibility of safe combination by simulating the interaction of hyperforin, a key compound in St. John’s Wort, with drugs metabolized by CYP3A4 that can be used to relieve various symptoms of depression. Understanding these interactions is crucial for optimizing the treatment of depression and associated symptoms. Results The hyperforin physiologically based pharmacokinetic (PBPK) model was validated against clinical data, and PBPK models for zolpidem, alprazolam, and midazolam were used to predict herb–drug interactions. The simulations with a two-week co-administration scenario showed that hyperforin potentially acts as a weak inducer (hyperforin dose 2–20 mg, 3 times a day, AUC ratio 0.8–0.68) of 10 mg zolpidem metabolism, with sex-dependent interactions largely unaffected. However, the pharmacokinetics of alprazolam at doses of 0.25, 0.5, and 1 mg were minimally impacted (hyperforin dose 1–20 mg, 3 times a day, AUC ratio 0.96–0.87). In the case of 7.5 mg midazolam, hyperforin acted as a moderate to strong inducer (hyperforin dose 1–20 mg, 3 times a day, AUC ratio 0.26–0.20), even at low doses. Conclusions These findings emphasize the importance of careful monitoring and dose adjustments when using hyperforin and sedative hypnotics together. This study provided insights into co-administration of hyperforin and sedative hypnotics, facilitating the safe and effective use of these medications. Based on these results, it is necessary to know the possibility of safer drug combination, and to conduct clinical research and verification on this.

Multiwire-electrical discharge machining process for silicon wafering for photovoltaics

Lee Wooyoung,Hirsch Jens,Jang Boyun 한국물리학회 2023 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.82 No.1

Multiwire-electrical discharge machining system and process has been developed, and Si wafers with dimension of 25×25×0.5 mm were obtained with 15 wires. So far, 15 wires are the maximum number to saw Si within voltage range we can control. The saw damages such as microstructural defects and metallic impurities were observed, and various removal methods such as plasma processing and chemical cleaning were studied. Typical defects were grooves, holes, craters and metallic impurities from consumable materials in process. Plasma processing and texturing were efective to remove microstructural defects, but need further research to completely remove micro holes on surface. For removal of metallic impurities, chemical cleaning by treatment was the most efective way. Through this study, we found requirements of further developments, such as wire tension control, replacement of wire with diferent materials, and so on. Nevertheless, we found the possibility of our technology to apply for Si wafering process with industrial level.

리튬이차전지 음극을 위한 실리콘 나노입자의 프리리시에이션이 미세구조 및 전기화학특성에 미치는 영향

김낙원(Nakwon Kim),김대일(Daeil Kim),장보윤(Boyun Jang),김준수(Junsoo Kim) 한국태양에너지학회 2021 한국태양에너지학회 학술대회논문집 Vol.2021 No.11