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Diversity and Composition of Tree Species in Madhupur National Park, Tangail, Bangladesh

  • Rahman, Md. Rayhanur;Hossain, Mohammed Kamal;Hossain, Md. Akhter
    • Journal of Forest and Environmental Science
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    • v.35 no.3
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    • pp.159-172
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    • 2019
  • Madhupur National Park (MNP) is one of the last remaining patches of old-growth natural Sal forest left in Bangladesh where the forest is tropical moist deciduous type. A study was revealed to assess the tree species diversity and composition in this area. For determining tree species the study was conducted through extensive random quadrat survey methods with $20m{\times}20m$ sized plots. Results of the study indicated that there were 139 tree species belonging to 100 genera and 40 families. The quadrat survey assessed the basal area, stem density, diversity indices and importance value index of the tree species having ${\geq}5cm$ D.B.H (Diameter at Brest Height). The basal area and stem density of the tree species were $20.689{\pm}1.08m^2/ha$ and $1412.93{\pm}64.27stem\;ha^{-1}$ while, diversity indices, i.e. Shannon-Wiener's diversity, Simpson's evenness, Margalef's species richness and Pielou's dominance indices indicated poor diversity in comparison to that of other PAs (Protected Areas) in South-Eastern region of Bangladesh. The structural composition based on height and D.B.H through reverse-J shaped curve indicated higher regeneration and recruitment but removal of trees of large growth classes. Sal (Shorea robusta) was the most dominant tree species that accounts 75% of the total tree individuals in the natural forest patches. However, some associates of Sal, i.e. Bhutum (Hymenodictyon orixensis), Gadila (Careya arborea), and Kusum (Schleichera oleosa) etc. were seemed to be rare in MNP.

Surface Modification of Nanofiltration Membrane with Silane Coupling Agents for Separation of Dye (실란 표면 개질된 나노복합막의 염료 분리 특성)

  • Park, Hee Min;Lim, Jee Eun;Kim, Seong Ae;Lee, Yong Taek
    • Membrane Journal
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    • v.28 no.6
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    • pp.414-423
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    • 2018
  • In this study, the commercial nanofiltration membranes were modified with octyltrimethoxysilane(OcTMS) and (3-aminopropyl)trimethoxysilane (APTMS) to improve fouling resistance and to separate dye. The chemical structure and binding energy of elements of silane-deposited surface were analyzed using XPS analysis. And the morphology and hydrophilicity property of silane-modified NF membrane were analyzed using FE-SEM, EDX, AFM, and contact angle. The surface charge of silane-modified NF membrane was characterized by zeta potentiometer analyzer. As a result, silane-modified NF membrane improved fouling resistance about 2 times as compared with that of the commercial membrane. And the silane-modified NF membranes effectively were removed cation dye over 98%.

Comparison of complete surgical excision and minimally invasive excision using CO2 laser for removal of epidermal cysts on the face

  • Kim, Keun Tae;Sun, Hook;Chung, Eui Han
    • Archives of Craniofacial Surgery
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    • v.20 no.2
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    • pp.84-88
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    • 2019
  • Background: Epidermal cysts are benign, slow growing cysts that often develop on the head, neck, chest, and back of adults. The most common method of surgical excision involves the use of a scalpel and often leaves a scar proportional to the size of the cyst. Therefore, minimally invasive techniques are required. Among these techniques, the $CO_2$ laser-based technique is minimally invasive and has lower complication rate, shorter recovery times, and lesser scarring. This paper aimed to compare the results and postoperative complications associated with a $CO_2$ laser-based excision against conventional surgical excision for epidermal cysts. Methods: We surveyed 120 patients, aged 16 to 65 years, with epidermal cysts on the face measuring 0.5 to 2.2 cm in diameter. Twelve months later, we compared the scar length, recurrence rate, patient satisfaction, and complications between patients treated with $CO_2$ laser excision versus surgical excision. Results: The mean scar length (12 months postoperative) after $CO_2$ laser excision was $0.30{\pm}0.15cm$, and that following surgical excision was $1.23{\pm}0.43cm$ (p= 0.001). The procedure time (time from incision after local anesthesia to the end of repair) was $16.15{\pm}5.96minutes$ for $CO_2$ laser excision versus $22.38{\pm}6.05minutes$ for surgical excision (p= 0.001). The recurrence rates in the surgical excision group and $CO_2$ laser excision group were 3.3% and 8.3%, respectively; this difference was not statistically significant (p= 0.648). Conclusion: The cosmetic outcome of $CO_2$ laser excision is excellent. For epidermal cysts measuring 2.2 cm or smaller, $CO_2$ laser excision is recommended, especially when aesthetic outcome is considered important.

A Study on High performance Electrical Precipitation Technology for PM Removal in Exhaust Gas (배가스 내 미세먼지 제거를 위한 고성능 집진 기술에 대한 연구)

  • Kim, Soyeon;Kim, Minsung;Choi, Sangmi;Jung, Minkyu;Lee, Jinwook
    • Plant Journal
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    • v.18 no.1
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    • pp.50-54
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    • 2022
  • The demand for high-efficiency dust collectors is rapidly increasing to remove PM from exhaust gas emission facilities, such as thermal power plants, steel mills, and industrial cogeneration plants, as the Pmemission standards have been strengthened. In this study, the electrospray is adapted for existing electrosratic precipitator(EP) to remedy its shortcomings and to improve the performance. Electrospray has been mainly used for the purpose of generating very fine droplets, but fir the purpose of EP, the flow rate over 10 mL/min per nozzleis required, and a high flow rate condition of 65 to 200 times is required. The electrospray of high flow rate has a completely different spray shape from the low flow rate condition, and was visualized through various figures such as corona discharge photographs and shadow images.

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Validation of the Risk Prediction Tool for Wound Infection in Abdominal Surgery Patients (복부 수술환자의 수술부위 감염 위험 예측 도구의 타당도 검증)

  • Jung, Hyun Kyoung;Lee, Eun Nam
    • Journal of Korean Critical Care Nursing
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    • v.15 no.3
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    • pp.75-87
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    • 2022
  • Purpose : This retrospective investigation study aimed to determine the predictive validity of superficial surgical site infection assessment tools by measuring the risk score at the surgical site. Methods : This study included patients hospitalized to the general surgery department of a Hospital from January 2021 to December 31, 2021. The inclusion criteria were age ≥19 years, general abdominal surgery under general anesthesia, and hospital stay longer than 2 days. Patients who had undergone transplantation were excluded. Results : Tool validity results showed that tools including surgical time and operative procedure were more accurate than previously developed tools, with a sensitivity of 71.1%, specificity of 71.4%, positive prediction of 12.3%, negative prediction of 97.8%, and area under the curve of 0.743 (95% confidence interval, 0.678~0.745). The tool's cut-off score was 15, and the risks of infection was increased by 6.14 times at or above this cut-off point. Preoperative hair removal period, surgical wound classification, surgery time, body temperature on the second day after surgery, drainage tube type, and suture type affected the risk of infection at the surgical site. Conclusion : The incidence of healthcare-associated infections has been declining in the past decade; however, surgical site infections still account for a considerable proportion. Therefore, early identification of high-risk groups for surgical site infection is crucial for reducing the incidence of surgical site infection using appropriate management.

Nutritional Composition of Rice with Embryo Part, Obongbyeo (배아미 오봉벼의 영양가)

  • Lee, Byoung-Young;Son, Jong-Rok;Kim, Young-Bae;Yoon, In-Wha;Chang, Chang-Moon;Shin, Dong-Kyu;Kim, Young-Sang
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.36 no.4
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    • pp.366-369
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    • 1991
  • This study was carried out to find out the properties of rice grain with embryo part. Obong-byeo. The embryo part on the rice remained by 96.7% in Obongbyeo after complete removal of the brans by common milling method. In nutritional composition. the content of lipid. vitamin B$_1$ and niacin were greater in Obongbyeo than Nagdongbyeo as a check variety. In particular. the contents of vitamin B$_1$ and niacin were about 1,5 times higher. Increased weight and feed effect of rat raising with milled rice were 107 and 172% in Obongbyeo and 101 and 125% in Nagdongbyeo. respectively. Eating quality of Obongbyeo was better than Nagdongbyeo.

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Photocatalytic and photoelectrocatalytic properties of anodic titanium dioxide nanotubes based on anodizing conditions (양극산화 조건에 따른 이산화티타늄 나노튜브의 광촉매 및 광전기화학적 특성)

  • Yeonjin Kim;Rin Jung;Jaewon Lee;JeongEun Yoo;Kiyoung Lee
    • Journal of Surface Science and Engineering
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    • v.56 no.2
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    • pp.137-146
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    • 2023
  • Nanosized TiO2 has been widely investigated in photoelectrochemical or photocatalytic applications due to their intrinsic properties such as suitable band position, high photocorrosion resistance, and surface area. In this study, to achieve the high efficiency in photoelectrochemical and photocatalytic performance, TiO2 nanotubular structures were formed by anodization at various temperatures and times. The morphological and crystal structure of the anodized TiO2 nanotubes (NTs) were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). The photoelectrochemical (PEC) properties and incident photon-to-current conversion efficiency (IPCE) of the TiO2 NTs were studied with different lengths and morphologies. From the detailed investigations, the optimum thickness of TiO2 nanotubes was 3 ㎛. Moreover, we found that the optimum photocatalytic pollutant removal efficiency of TiO2 nanotubes for photodegradation of Rhodamine B (RhB) under simulated solar light was 5.34 ㎛ of tube length.

Risk Assessment of Azoxystrobin Residues in Fresh Crown Daisy from Farm to Fork (생산단계에서 소비단계 생식 쑥갓의 azoxystrobin 잔류량에 따른 위해성 평가)

  • Sun-Woo Ban;A-Yeon Oh;Hee-Ra Chang
    • Korean Journal of Environmental Agriculture
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    • v.42 no.2
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    • pp.131-138
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    • 2023
  • The biological half-life and dissipation rate of azoxystrobin in crown daisy were calculated to establish the pre-harvest residue limits (PHRLs). The pesticide residues were calculated after washing with five different processes to propose an effective process in the household and conducted a risk assessment to confirm dietary safety. Azoxystrobin was sprayed according to the critical good agricultural practices (cGAP) in two different field trials, and the samples were harvested 7 times. The limit of quantitation was 0.02 mg/kg, and the mean recoveries of azoxystrobin were within the range of 70~120% with below 20% coefficient variation at the concentration of 0.02 and 0.2 mg/kg . The biological half-lives were 7.4 and 4.7 days, and the dissipation rate constants were 0.0872 and 0.1217 in fields 1 and 2, respectively. The average removal rates were 58.13~78.13% by the different washing processes, and there were significant differences between the washing processes (one-way ANOVA analysis and post-hoc Duncan test, p-value<0.05). The residues of azoxystrobin in crown daisy were safe levels from farm to fork after application with the critical good agricultural practice (cGAP) registered in Korea.

A study on thermal fluid analysis in X-ray tube for non-fire alarm (비화재보를 위한 X-ray tube 내 열 유동해석에 관한 연구)

  • Yun, Dong-Min;Jeon, Yong-Han
    • Design & Manufacturing
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    • v.16 no.2
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    • pp.33-38
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    • 2022
  • Currently, Korea is an aging society, and it is expected to enter a super-aging society in about 4 years. Accordingly, many X-ray technologies are being developed. In X-rays, 99% of X-rays are converted into heat energy and 1% into light energy (X-rays). 99% of the thermal energy raises the temperature of the anode and its surroundings, and the cooling system is an important factor as overheating can affect the deterioration of X-ray quality and shortened lifespan. There is a method of forced air cooling using natural convection. Therefore, in this study, when X-rays were taken 5 times, Flow analysis was performed on heat removal according to temperature rise and cooling time for the heat generated at the anode of the X-ray tube (input power 60kW, 75kW, 90kW). Based on one-shot, the most rapid temperature rise section increased by more than 57% to 0.03 seconds, A constant temperature rises from 0.03 seconds to 0.1 seconds, It is judged that the temperature rises by about 8.2% or more at one time. After one-shot cooling, the cooling drops sharply from about 60% to 0.03 seconds, It is judged that the temperature has cooled by more than 86% compared to the temperature before shooting. One-shot is cooled by more than 86% with cooling time after 0.1 seconds, As the input power of the anode increases, the cooling temperature gradually increases. Since the tungsten of the anode target inside the X-ray tube may be damaged by thermal shock caused by a rapid temperature rise, an improvement method for removing thermal energy is required when using a high-input power supply.

Resin infiltrant protects deproteinized dentin against erosive and abrasive wear

  • Ana Theresa Queiroz de Albuquerque;Bruna Oliveira Bezerra;Isabelly de Carvalho Leal;Maria Denise Rodrigues de Moraes;Mary Anne S. Melo;Vanara Florencio Passos
    • Restorative Dentistry and Endodontics
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    • v.47 no.3
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    • pp.29.1-29.10
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    • 2022
  • Objectives: This study aimed to investigate the anti-erosive/abrasive effect of resin infiltration of previous deproteinized dentin. Materials and Methods: Dentin slabs were randomly assigned to 3 groups (n = 15): Control (no deproteinization; no resin infiltrant applied), RI (no deproteinization; resin infiltrant applied), and DRI (deproteinization; resin infiltrant applied). After undergoing the assigned treatment, all slabs were subjected to an in vitro cycling model for 5 days. The specimens were immersed in citric acid (0.05 M, pH = 3.75; 60 seconds; 3 times/day) and brushed (150 strokes). Between the challenges, the specimens were exposed to a remineralizing solution (60 minutes). The morphological alterations were analyzed by mechanical profilometry (㎛) and scanning electron microscopy (SEM). Data were submitted to one-way analysis of variance (ANOVA) and Tukey tests (p < 0.05). Results: Control and RI groups presented mineral wear and did not significantly differ from each other (p = 0.063). DRI maintained a protective layer preserving the dentin (p < 0.001). After erosive/abrasive cycles, it was observed that in group RI, only 25% of the slabs partially evidenced the presence of the infiltrating, while, in the DRI group, 80% of the slabs presented the treated surface entirely covered by a resin-component layer protecting the dentin surface as observed in SEM images. Conclusions: The removal of the organic content allows the resin infiltrant to efficiently protect the dentin surface against erosive/abrasive lesions.