• Carbon letters
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• v.16 no.3
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• pp.183-191
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• 2015

Gas transport through graphene-derived membranes has gained much interest recently due to its promising potential in filtration and separation applications. In this work, we explore Kr-85 gas radionuclide sequestration from natural air in nanoporous graphene oxide membranes in which different sizes and geometries of pores were modeled on the graphene oxide sheet. This was done using atomistic simulations considering mean-squared displacement, diffusion coefficient, number of crossed species of gases through nanoporous graphene oxide, and flow through interlayer galleries. The results showed that the gas features have the densest adsorbed zone in nanoporous graphene oxide, compared with a graphene membrane, and that graphene oxide was more favorable than graphene for Kr separation. The aim of this paper is to show that for the well-defined pore size called P-7, it is possible to separate Kr-85 from a gas mixture containing Kr-85, O₂ and N₂. The results would benefit the oil industry among others.

• Clinical and Experimental Pediatrics
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• v.52 no.1
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• pp.1-5
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• 2009

Children are not small adults and there is a need to carry out specific trials that cannot be performed in adults. In general, children (minors) are unable to consent but their assent should be obtained using age appropriate information. Institutional Review Board (IRB) need paediatric expertise to balance the benefits and risks of research in children. The lack of consent has implications on the design, analysis and the choice of comparators used in the trials, which should only be performed by trained investigators with paediatric experience. Pain, fear, distress and parental separation should be prevented and minimised when unavoidable. The children requires even more careful review. Children represent a vulnerable population with developmental, physiological and psychological differences from adults, which make age- and development- related research important for their benefit. Finally, criteria for the protection of children in clinical trials therefore need to be laid down. Specific protection should be defined for research performed in children, at all stages and ages.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.05a
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• pp.1047-1051
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• 2004

Charge amplifier systems benefit from the very wide dynamic range of PE accelerometers by offering flexibility in adjusting the electrical output characteristics such as sensitivity and range. They are well suited for operation at high temperatures. Modern charge systems feature improved low noise operation, simplified digital controls, and dual mode operation for operation with charge or IEPE voltage mode sensors. high impedance circuitry is not well suited for operation in adverse field or factory environments. The resolution of a PE accelerometer may not be specified or known since noise is a system consideration determined by cable length and amplifier gain. IEPE accelerometrs operate from a constant current power source, provide a high-voltage, low-impedance, fixed mV/g output. They operate through long, ordinary, coaxial cable in adverse environments without degradation of signal quality. They have limited high temperature range. IEPE sensors are simple to operate. Both resolution and operating range are defined specifications. Cost perchannel is lower compared to PE systems since low-noise cable and charge amplifiers are not required.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.14
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• pp.5589-5594
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• 2015

Cystitis and proctitis are defined as inflammation of bladder and rectum respectively. Haemorrhagic cystitis is the most severe clinical manifestation of radiation and chemical cystitis. Radiation proctitis and cystitis are major complications following radiotherapy. Prevention of radiation-induced haemorrhagic cystitis has been investigated using various oral agents with minimal benefit. Bladder irrigation remains the most frequently adopted modality followed by intra-vesical instillation of alum or formalin. In intractable cases, surgical intervention is required in the form of diversion ureterostomy or cystectomy. Proctitis is more common in even low dose ranges but is self-limiting and improves on treatment interruption. However, treatment of radiation proctitis is broadly non-invasive or invasive. Non-invasive treatment consists of non-steroid anti-inflammatory drugs (NSAIDs), anti-oxidants, sucralfate, short chain fatty acids and hyperbaric oxygen. Invasive treatment consists of ablative procedures like formalin application, endoscopic YAG laser coagulation or argon plasma coagulation and surgery as a last resort.

• Korean Journal of Computational Design and Engineering
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• v.21 no.3
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• pp.306-312
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• 2016

In general, the shape of a 3D printed object is not to be changed after the generation. Most changes, for example, contraction of a molten polymer after cooling is thought to be undesirable. 4D printing however tries to make benefit of a shape change after the part is generated. The shape change is required to be controllable in response to an external stimuli. These artifacts from 4D printing are called kinetic components which are defined as structures formed by combining inert materials and smart materials that change under certain stimuli. We propose a design software that can systematically calculate inert links with smart joints to follow the shape of the target design.

• Journal of Korean society of Dental Hygiene
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• v.16 no.5
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• pp.669-676
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• 2016

Objectives: The purpose of the study was to investigate the related factors of scaling experience of multi-cultural adolescents in Korea. Methods: The subjects were 698 multi-cultural adolescents from web-based survey of the 11th(2015) Korean Youth Risk Behavior. Multi-cultural adolescents are defined as the children of marriage migrant women. The study instruments included demographical characteristics of the subjects, oral health behaviors, daily tooth brushing times, health behaviors, and experience of smoking and alcohol consumption. Data were analyzed using PASW statistics 18.0. Results: The experience rate of scaling was 18.8%. Multiple logistic regression analysis revealed that experience of scaling were related with experiences of sealant and fruit consumption. Conclusions: It is very important to provide the continuing oral health prevention program for the adolescents and investigate the cost-benefit effectiveness of oral health care program.

• Journal of Dairy Science and Biotechnology
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• v.26 no.2
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• pp.31-37
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• 2008

One hundred one years have passed since Metchnikoff made his first scientific contribution to probiotics study. Intestinal lactic acid bacteria (LAB) for humans are closely associated with the host's health because LAB is an important biodefense factor in preventing colonization and subsequent proliferation of pathogenic bacteria in the intestine. A probiotic is recently defined as "live microorganisms that when administered in adequate amount confer a health benefit on the host". Some species of LAB have been claimed as probiotics, such as Lactobacillus acidophilus, L. casei, L. fermentum, L. plantarum, L. reuteri, and Lactococcus lactis. For understanding the general mechanism of probiotics, this paper would explore the early studies relating to probiotics and intestinal microbiota, and briefly introduce the Prolongation of Life written by Elie Metctmikoff.

• Korean Journal of Bronchoesophagology
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• v.5 no.1
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• pp.62-67
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• 1999

Sternal recurrence has been defined as a diffuse infiltrate of neoplastic tissue at the junction of the amputated trachea and the skin. The overall prognosis is poor, resulting from progressive tracheostomal obstruction or massive hemorrhage due to erosion of major vessels. Neither radiation therapy nor chemotherapy has demonstrated any efficacy in controlling these sternal recurrence. Surgery, especially mediastinal dissection, may benefit only an occasional patient. Recently authors experienced one case of mediastinal dissection for sternal recurrence after total laryngectomy for laryngeal cancer. We report our case with a brief review of literature.

• Journal of Microbiology and Biotechnology
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• v.20 no.10
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• pp.1367-1377
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• 2010

Scientific research regarding the use of live bacterial cells for therapeutic purposes has been rapidly growing over the years and has generated considerable interest to scientists and health professionals. Probiotics are defined as essential live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. Owing to their considerable beneficial health effects, these microorganisms are increasingly incorporated into dairy products; however, many reports have demonstrated their poor survival and stability. Their survival in the gastrointestinal tract is also questionable. To overcome these problems, microencapsulation techniques are currently receiving considerable attention. This review describes the importance of live probiotic bacterial microencapsulation using an alginate microparticulate system and presents the potentiality of various coating polymers such as chitosan and polylysine for improving the stability of this microencapsulation.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2001.05a
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• pp.133-138
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• 2001

Formal safety assessment (FSA) is defined as a structured and systematic methodology aimed at enhancing maritime safety including protection of life, health, and the marine environment and property, by using risk and cost/benefit assessment or, more specifically, it is a process of identifying hazard, evaluating risk and deciding on course of action to control those risks. Emphasis is placed on the structural aspect of the failure of cargo hold. This study is expected to illustrate how a new methodology, i.e. the Formal Safety Assessment, can be applied to specific ship safety problems.