• Title/Summary/Keyword: alternating groups

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Three-Dimensional Metal Complex Host with Alternating Arrangement of the Occupied and Vacant Channels. The Crystal Structure of Cd(NH₂CH(CH₃)CH₂NH₂)Ni(CN)₄· 0.25G (G=$CH_3C_6H_5, p-(CH_3)_2C_6H_4$)

  • 박기민;이욱;Toschitake Iwamoto
    • Bulletin of the Korean Chemical Society
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    • v.17 no.10
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    • pp.919-924
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    • 1996
  • Crystal structure of two inclusion compounds Cd(pn)Ni(CN)4·0.25G (G=toluene and p-xylene, pn=1,2-diaminopropane) have been determined from single-crystal X-ray diffraction data; toluene clathrate: monoclinic P21/n, a=13.838(6), b=26.893(5), c= 7.543(5) Å, γ=90.92(3)°, Z=4, R=0.0616; p-xylene clathrate: monoclinic P21/n, a=13.895(2), b=26.900(3), c=7.613(1) Å, γ=91.06(1)°, Z=4, R=0.0486. The host structures determined for toluene- and pxylene-guest clathrates are substantially identical to the U-type structures observed for the straight chain aliphatic-guest clathrates. However, the alternating arrangement of occupied channels with the guest molecules and vacant channels appears in the host structure. The non-centrosymmetric toluene molecules are distributed about the inversion center to give an image like p-xylene molecule. The guests, toluene and p-xylene, prefer the U-type channel, favoring the interaction between the π-electrons of the aromatic ring and the pn-amino groups to hold the aromatic ring vertical to the cyanometallate meshes.

Etoposide-Cisplatin Alternating with Vinorelbine-Cisplatin Versus Etoposide-Cisplatin Alone in Patients with Extensive Disease Combined with Small Cell Lung Cancer

  • Zhang, Jie;Qi, Hui-Wei;Zheng, Hui;Chen, Mo;Zhu, Jun;Xie, Hui-Kang;Ni, Jian;Xu, Jian-Fang;Zhou, Cai-Cun
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.10
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    • pp.4159-4163
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    • 2014
  • Background: The aim of this study was to evaluate the efficacy of alternating etoposide-cisplatin and vinorelbine-cisplatin (EP-NP) compared with an etoposide-cisplatin (EP) regimen for advanced combined small cell carcinomas. Materials and Methods: Histologically confirmed combined small cell carcinoma patients who met the inclusion criteria were randomly assigned (1:1) into either the EP-NP setting (group A) or the EP setting (group B). The primary endpoint was progression-free survival in patients who received at least one dose of treatment. Results: Eighty-two patients entered into this trial, 42 in group A and 40 in group B. The objective response rates in group A and group B were 42.9% and 32.5%, respectively (p=0.334). Survival analysis showed that median progression-free survival was 6.1 months in group A, which was significantly longer than the 4.1 months in group B (p=0.041). However, as to overall survival, no significant difference was found between the two groups (11.0 vs 10.1 months in groups A and B, respectively, p=0.545). No unexpected side effects were observed in either group. Conclusions: The EP-NP regimen for combined small cell carcinomas prolonged progressio-nfree survival compared with the EP regimen. Further clinical investigations are warranted.

Studies on the Maximum Transfer Rate of Printing Ink (인쇄 잉크의 최대 전이율에 관한 연구)

  • 강상훈
    • Journal of the Korean Graphic Arts Communication Society
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    • v.13 no.1
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    • pp.1-12
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    • 1995
  • Polymeric mesogens having a regularly alternating rigid-flexible repeating structure in the main-chain polymer exhibit distinct even-odd oscillation in their thermodynamic quantities with respect to the number of methylene units in the spacer. The even-odd oscillation depends on the number of methylene groups in the spacer the entropy change at the NI(nematic-isotropic) phase transition becomes less distinct when the linking group is replaced by the carbonate. In our previous work, we have suggested that the characteristics arise from the geometrical arrangement of the linkage. In this work, we have prepared a series of carbonate-type monomer and dimer liquid crystals. The thermodynamic behaviors at the NI phase transition have been compared with those previous reported for the ether- or ester-type liquid crystals. For the dimer series, the orientational order parameter of the mesogenic core was determined by using H-NMR technique. The origin of the difference observed among linking groups was found to the geometrical characteristics of chemical structure.

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The Effect of an Orofacial Exercise Program using PNF on Diadochokinesis in Subacute Stroke Patients with Dysarthria (PNF 구강안면 운동 프로그램이 마비말장애가 있는 아급성 뇌졸중 환자의 교대운동속도와 연속운동속도에 미치는 효과)

  • Won, Young-Sik;Lee, Soon-Hyun;Kim, Kye-Ho;Moon, Jong-Hoon
    • PNF and Movement
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    • v.16 no.3
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    • pp.475-484
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    • 2018
  • Purpose: The aim of the present study was to investigate the effect of a PNF orofacial exercise program on diadochokinesis in subacute stroke patients with dysarthria. Methods: Thirteen subacute stroke inpatients with dysarthria were recruited for the study. All participants were randomly assigned to two groups: an experimental group (n=7) and a control group (n=6). The experimental group performed a PNF orofacial exercise program, and the control group carried out an orofacial self-exercise. Both groups received the treatments 30 minutes per day, 5 days per week, for 4 weeks. The outcome measures were assessed before and after the intervention, including an alternating motion rate (AMR) and sequential motion rate for diadochokinesis. Results: After the intervention, both groups showed significant improvement in diadochokinesis (p<0.05). In the change values for both groups, the experimental group showed a more significant improvement than the control group did in /pə/ of AMR (p<0.05). Conclusion: These findings suggest that PNF orofacial exercise programs may have positive effects on the improvement of diadochokinesis in subacute stroke patients with dysarthria.

Effect of Interface Reaction between ZnO:Al and Amorphous Silicon on Silicon Heterojunction Solar Cells (실리콘 이종 접합 태양 전지 특성에 대한 ZnO:Al과 비정질 실리콘 계면 반응의 영향)

  • Kang, Min-Gu;Tark, Sung-Ju;Lee, Jong-Han;Kim, Chan-Seok;Jung, Dae-Young;Lee, Jung-Chul;Yoon, Kyung-Hoon;Kim, Dong-Hwan
    • Korean Journal of Materials Research
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    • v.21 no.2
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    • pp.120-124
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    • 2011
  • Silicon heterojunction solar cells have been studied by many research groups. In this work, silicon heterojunction solar cells having a simple structure of Ag/ZnO:Al/n type a-Si:H/p type c-Si/Al were fabricated. Samples were fabricated to investigate the effect of transparent conductive oxide growth conditions on the interface between ZnO:Al layer and a-Si:H layer. One sample was deposited by ZnO:Al at low working pressure. The other sample was deposited by ZnO:Al at alternating high working pressure and low working pressure. Electrical properties and chemical properties were investigated by light I-V characteristics and AES method, respectively. The light I-V characteristics showed better efficiency on sample deposited by ZnO:Al by alternating high working pressure and low working pressure. Atomic concentrations and relative oxidation states of Si, O, and Zn were analyzed by AES method. For poor efficiency samples, Si was diffused into ZnO:Al layer and O was diffused at the interface of ZnO:Al and Si. Differentiated O KLL spectra, Zn LMM spectra, and Si KLL spectra were used for interface reaction and oxidation state. According to AES spectra, sample deposited by high working pressure was effective at reducing the interface reaction and the Si diffusion. Consequently, the efficiency was improved by suppressing the SiOx formation at the interface.

Relationship between Alternating Attention and Context Use during Sentence Processing in Older and Younger Adults (정상노인과 젊은 성인의 문맥을 이용한 문장처리와 교대주의력의 관계)

  • Park, Youngmi
    • The Journal of the Korea Contents Association
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    • v.18 no.11
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    • pp.527-539
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    • 2018
  • Cognitive decline in aging is known to yield detrimental effects in syntactic processing and working memory capacity is the most crucial cognitive function in understanding older adults' sentence processing skills. This study examined how young and older adults utilize contextual information while resolving NP-attached Ps vis word-by-word self-paced reading paradigm. In addition, the study asked which cognitive functions play roles on the use of a NP-supporting context during processing of NP-attached PP. When NP-attached PP was presented in a supporting context, both age groups performed faster than in the null context condition. Among different cognitive functions, alternating attention skills were correlated with the ability utilizing context during syntactic ambiguity resolution and working memory capacity was not found to be crucial for this study. In conclusion, this study suggests that aging does not always affect older adults' syntactic processing negatively and relevant cognitive function may vary depending on the type of syntactic structure.

Poly(ether-ester) Multiblock Copolymers Based on Poly(oxymethylene-alt-oxyalkylene) Glycols

  • Kim, Jin-Bong;Chun, Jae-Hwan;Kim, Dong-Hee;Park, Yun-Hee;Lee, Moo-Sung
    • Macromolecular Research
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    • v.10 no.4
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    • pp.230-235
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    • 2002
  • Alternating polyols of oxymethylene and oxyalkylene were synthesized and used as precursors for thermoplastic poly(ether-ester) elastomers (TPEs). The polyols were synthesized by reacting diols having different methylene units with dichloromethane in the presence of a phase transfer catalyst. The number of methylene units in the alkylene oxides was varied from 3 to 6. TPEs were prepared using the polyols as soft segments and poly(butylene terephthalate) units as hard segments. The polyols and TPEs synthesized were characterized using FTIR, NMR, GPC, DSC, and polarized optical microscopy. The polyols showed a profound odd-even effect on the melting (T$_{m}$) and glass transition temperatures (T$_{g}$). Polyols with odd numbers of methylene groups in the alkylene units have higher transition temperatures than polyols with odd number of methylene groups. The tendency is still kept in TPEs, even though the T$_{g}$ of soft segment in TPEs are slightly higher than those of corresponding neat polyols. The T$_{m}$ and T$_{g}$ of soft segments are almost constant in the range of 20 to 60 wt % contents of soft segments. On the other hand, the normalized heat of fusion of hard segment decreased with increasing the content of loft segment.ent.t.ent.

Traction Effects for the Treatment of Scoliosis (척추 측만증에 대한 견인 치료의 효과)

  • Shim, Jae-Hun;Oh, Duck-Won
    • Physical Therapy Korea
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    • v.3 no.3
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    • pp.12-23
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    • 1996
  • The purpose of this research is to identify traction effects for the treatment of scoliosis and compare the effects among patients as their own physical characters. In this research, the patients with scoliosis hospitalized for ten days have treated in the way of the static traction for twenty hours a day, and alternating lumbar and cervical traction for twenty minutes two times a day in the department of rehabilitaton of Yong-Dong Severance Hospital. The followings are the conclusions of this research: 1) The traction for the patients with scoliosis is effective treatment method to reduce the curved angle (p<0.001). 2) Statistically there is no significant difference of the reduced curved angle between male and female after the traction (P>0.05). 3) Statistically there is significant difference of the reduced curved angle among age groups after the traction (P<0.05). 4) Statistically there is significant difference of the reduced curved angle among curved angle groups after the traction (p<0.001). 5) Statistically there is no significant difference of the reduced curved angle among shapes of curved angle after the traction (P>0.05).

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Investigations on ionic polymer actuators based on irradiation-crosslinked sulfonated poly(styrene-ran-ethylene)

  • Wang, Xuan-Lun;Oh, Il-Kwon;Xu, Liang
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2009.10a
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    • pp.316-317
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    • 2009
  • The ion-exchange membrane, Nafion, remains as the benchmark for a majority of research and development in IPMC technology. In this research, we employed a novel ionomer named by sulfonated poly(styrene-ran-ethylene) (SPSE) that is crosslinked by UV irradiation. The sulfonic acid groups were stable during the UV irradiation crosslinking process. Water uptake, ion exchange capacity, and proton conductivity are characterized for both pure SPSE and crosslinked SPSE membrane. The bending responses of SPSE actuators under both direct current (DC) and alternating current (AC) excitations were investigated. The voltage-current behaviors of the actuators under AC excitations are also measured. Results showed the crosslinked SPSE actuators have better electromechanical performance than that of pure SPSE actuator with regard to tip displacement as a novel smart material.

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Synthesis and Biological Activity of Poly[(tri-O-acetyl-D-glucal)-alt-(maleic anhydride)] Derivatives

  • Han, Man-Jung;Lee, Choong-Whan;Kim, Ki-Ho;Lee, Won-Young
    • Bulletin of the Korean Chemical Society
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    • v.12 no.1
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    • pp.85-87
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    • 1991
  • Poly[(tri-O-acetyl-D-glucal)-alt-(maleic anhydride)] was synthesized by free radical copolymerizations of the relevant comonomers. The alternating sequence of the copolymer was confirmed by $^1$H-NMR, elemental analysis, and titration of anhydride groups incorporated into the copolymer. Hydrolysis of the copolymer under different conditions resulted in poly[(2-acetoxymethyl-3,4-diacetoxytetrahydropyran-5,6-diyl) (1,2-dicarboxyethylene)] and poly[(2-hydroxymethyl-3,4-dihydroxytetrahydropyran-5,6-diyl) (1,2-dicarboxyethylene)]. The cytotoxicities of these polymers measured against normal and tumor cells (3LL, B16) in vitro were found to be higher than that of DIVEMA, a prototype polymer having a high antitumor activity.