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Selective Algicidal Effects of a Newly Developed GreenTD against Red Tide Harmful Alga (GreenTD 물질을 이용한 유해 적조 발생 종의 선택적 살조능 평가)

  • Lee, Minji;Shin, Juyong;Kim, Jin Ho;Lim, Young Kyun;Cho, Hoon;Baek, Seung Ho
    • Korean Journal of Environmental Biology
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    • v.36 no.3
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    • pp.359-369
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    • 2018
  • Harmful algal blooms (HABs) are a serious problem for public health and fisheries industries, thus there exists a need to investigate the possible ways for effective control of HABs. In the present study, we investigated the algicidal effects of a newly developed GreenTD against the HABs (Chattonella marina, Heterosigma akashiwo, Cochlodinium polykriokides, and Heterocapsa circularisquama) and non-HABs (Chaetoceros simplex, Skeletonema sp. and Tetraselmis sp.), which is focused on the different population density and concentration gradients of algicidal substances. The time series viability of target alga was assessed based on the activity of Chl. a photosynthetic efficiency in terms of $F_v/F_m$, and in vivo fluorescence (FSU). Effective control of Raphidophyta, C. marina and H. akashiwo was achieved at a GreenTD concentration of $0.5{\mu}gL^{-1}$ and $0.2{\mu}gL^{-1}$, respectively, and regrowth of both the species was not observed even after 14 days. The inhibitory ratio of the dinoflagellate, C. polykriokides was more than 80% at $0.2{\mu}gL^{-1}$ of GreenTD. H. circularisquama was constantly affected in the presence of $0.2{\mu}gL^{-1}$ of GreenTD in the high- and low-population density experimental groups. On the other hand, diatoms, C. simplex, and Skeletonema sp. were not significantly affected even in the presence of $0.2{\mu}gL^{-1}$ of GreenTD and exhibited re-growth activity with the passage of incubation time. In particular, green alga Tetraselmis sp. remained unaffected even in the presence of the highest concentration of GreenTD ($1.0{\mu}gL^{-1}$), implying that non-HABs were not greatly influenced by the algicidal substances. As a result, the algicidal activity of GreenTD on the harmful and nonharmful algae was as follows: raphidophyte>dinoflagellates>diatoms>green alga. Consequently, our results indicate that inoculation of GreenTD substances into natural blooms at a threshold concentration ($0.2{\mu}gL^{-1}$) can maximize the algicidal activity against HABs species. If we consider the dilution and diffusion rate in the field application, it is hypothesized that GreenTD will demonstrate economic efficiency, thus leading to effective control against the target HABs in the closed bay.

Needs and Related Factors for Return-to-Work Support in Cancer Survivors (암 경험자의 직장복귀지원에 대한 요구도 및 관련 요인)

  • Lee, Sungwon;Lee, Kwang-Min;Oh, Gyu-Han;Yeom, Chan-Woo;Jung, Sanghyup;Hahm, Bong-Jin
    • Korean Journal of Psychosomatic Medicine
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    • v.28 no.2
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    • pp.126-134
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    • 2020
  • Objectives : The purpose of this study was to investigate the needs for return-to-work support of cancer survivors and related factors in patients with cancer and their caregivers. Methods : 182 patients and 114 caregivers were recruited. Distress Thermometer and Problem List and scale ranging 0~10 measuring the degree of needs for return-to-work support were utilized. The needs for return-to-work support between the patient group and caregiver group (patient's needs evaluated by the caregiver) were compared, and related factors were investigated using logistic regression analysis. Results : 34.6% and 28.1% of patients and caregivers reported return-to-work support of cancer survivors is "very necessary". The degree of needs was 6.60±3.365 points in the patient group and 6.17±3.454 points in the caregiver group, with no significant difference (p=0.282). The needs for return-to-work support evaluated by patients was high when they underwent surgery (OR=2.592, p=0.007), has fertility problems (OR=6.137, p=0.025), has appearance problems (OR=2.081, p=0.041), or has fatigue (OR=2.330, p=0.020). The needs for return-to-work support of patients evaluated by caregivers was high when patients treated with breast cancer (vs respiratory cancer, OR=13.038, p=0.022 ; vs leukemia/lymphoma, OR=4.517, p=0.025 ; vs other cancer, OR=13.102, p=0.019), has work/school problems (OR=4.578, p=0.005), or has depression (OR=3.213, p=0.022). Conclusions : The degree of needs for return-to-work support of cancer survivors was high, and factors related to the needs were different between the two groups. This suggests that return-to-work support of cancer survivors is required, and clinical characteristics, the distress of patients, and differences between patients and their caregivers should be considered in establishing a support plan.

The Diagnostic Accordance between Transcranial Doppler and MR Angiography in the Intracranial Artery Stenosis (두개강내 혈관 협착에 대한 경두개도플러와 자기공명 혈관조영술의 일치도 평가)

  • Moon, Sang-kwan;Jung, Woo-sang;Park, Sung-uk;Park, Jung-mee;Ko, Chang-nam;Cho, Ki-ho;Bae, Hyung-sup;Kim, Young-suk;Cho, Seong-il
    • The Journal of the Society of Stroke on Korean Medicine
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    • v.7 no.1
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    • pp.11-16
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    • 2006
  • Objectives : Transcranial Doppler (TCD) has been reported to be established as useful in detecting spasm after subarachnoid hemorrhage and to be probably useful in diagnosing stenosis or occlusion in intracranial arteries. In the detection of intracranial stenosis using TCD there have been reported some kinds of diagnostic criteria. This study was aimed to evaluate the accordance between TCD and magnetic resonance angiography (MRA) in detection of intracranial stenosis and to find out more accurate criteria for intracranial stenosis using TCD. Methods : Seventy-six stroke patients were evaluated by TCD and MRA. TCD criteria for middle cerebral artery (MCA) stenosis were used by 3 methods; ≥ 80cm/sec of mean velocity(Vm), ≥ 140 cm/sec of systolic velocity(Vs), and both. For stenosis of vertebral(VA) and basilar arteries(BA), the TCD criteria followed by 2 methods; ≥ 70 cm/sec of Vm and ≥ 100 cm/sec of Vs. The stenosis of intracranial artery in MRA followed by the interpretation of specialist in the department of radiology. The sensitivity, specificity, positive predictive value, negative predictive value, diagnostic accuracy and kappa agreement were calculated in each criteria of TCD compared with the result of MRA. Results : The sensitivity, specificity, positive predictive value, negative predictive value, diagnostic accuracy and kappa agreement using ≥ 80cm/sec of Vm for MCA stenosis were 55.6%, 81%, 34.5%, 91.0%, 77.1%, and 0.293, respectively. Using 140 cm/sec of Vs, those were 44.4%, 92.0%, 50.5%, 90.2%, 84.7%, 0.380, and using both criteria those were 44.4%, 95.0%, 61.5%, 90.5%, 87.3%, 0.445, respectively. Those using ≥ 70 cm/sec of Vm for VA and BA stenosis were 71.4%, 93.7%, 26.3%, 99.0%, 93.0%, 0.186 and using ≥ 100 cm/sec of Vs those were 71.4%, 97.3%, 45.5%, 99.1%, 96.5%, 0.539, respectively. Conclusion : These results suggested that for the diagnosis of MCA stenosis using TCD we should use the criteria of both ≥ 80cm/sec of Vm and 140 cm/sec of Vs, and for the VA and BA stenosis we adapt the criteria of ≥ 70 cm/sec of Vm.

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Usefulness Evaluation of Artifacts by Bone Cement of Percutaneous Vertebroplasty Performed Patients and CT Correction Method in Spine SPECT/CT Examinations (척추 뼈 SPECT/CT검사에서 경피적 척추성형술 시행 환자의 골 시멘트로 인한 인공물과 CT보정방법의 유용성 평가)

  • Kim, Ji-Hyeon;Park, Hoon-Hee;Lee, Juyoung;Nam-Kung, Sik;Son, Hyeon-Soo;Park, Sang-Ryoon
    • The Korean Journal of Nuclear Medicine Technology
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    • v.18 no.1
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    • pp.49-61
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    • 2014
  • Purpose: With the aging of the population, the attack rate of osteoporotic vertebral compression fracture is in the increasing trend, and percutaneous vertebroplasty (PVP) is the most commonly performed standardized treatment. Although there is a research report of the excellence of usefulness of the SPECT/CT examination in terns of the exact diagnosis before and after the procedure, the bone cement material used in the procedure influences the image quality by forming an artifact in the CT image. Therefore, the objective of the research lies on evaluating the effect the bone cement gives to a SPECT/CT image. Materials and Methods: The images were acquired by inserting a model cement to each cylinder, after setting the background (3.6 kBq/mL), hot cylinder (29.6 kBq/mL) and cold cylinder (water) to the NEMA-1994 phantom. It was reconstructed with Astonish (Iterative: 4 Subset: 16), and non attenuation correction (NAC), attenuation correction (AC+SC-) and attenuation and scatter correction (AC+SC+) were used for the CT correction method. The mean count by each correction method and the count change ratio by the existence of the cement material were compared and the contrast recovery coefficient (CRC) was obtained. Additionally, the bone/soft tissue ratio (B/S ratio) was obtained after measuring the mean count of the 4 places including the soft tissue(spine erector muscle) after dividing the vertebral body into fracture region, normal region and cement by selecting the 20 patients those have performed PVP from the 107 patients diagnosed of compression fracture. Results: The mean count by the existence of a cement material showed the rate of increase of 12.4%, 6.5%, 1.5% at the hot cylinder of the phantom by NAC, AC+SC- and AC+SC+ when cement existed, 75.2%, 85.4%, 102.9% at the cold cylinder, 13.6%, 18.2%, 9.1% at the background, 33.1%, 41.4%, 63.5% at the fracture region of the clinical image, 53.1%, 61.6%, 67.7% at the normal region and 10.0%, 4.7%, 3.6% at the soft tissue. Meanwhile, a relative count reduction could be verified at the cement adjacent part at the inside of the cylinder, and the phantom image on the lesion and the count increase ratio of the clinical image showed a contrary phase. CRC implying the contrast ratio and B/S ratio was improved in the order of NAC, AC+SC-, AC+SC+, and was constant without a big change in the cold cylinder of the phantom. AC+SC- for the quantitative count, and AC+SC+ for the contrast ratio was analyzed to be the highest. Conclusion: It is considered to be useful in a clinical diagnosis if the application of AC+SC+ that improves the contrast ratio is combined, as it increases the noise count of the soft tissue and the scatter region as well along with the effect of the bone cement in contrast to the fact that the use of AC+SC- in the spine SPECT/CT examination of a PVP performed patient drastically increases the image count and enables a high density of image of the lesion(fracture).

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