Multi-jet electrospinning of polystyrene/polyamide 6 blend: thermal and mechanical properties

Citation: Yoon, J. W., Park, Y., Kim, J., & Park, C. H. (2017). Multi-jet electrospinning of polystyrene/polyamide 6 blend: thermal and mechanical properties. Fashion and Textiles, 4, 12. doi:10.1186/s40691-017-0090-4Polystyrene (PS) has high thermal resistance thus can be applied as thermally comfortable textile. However, the application is limited due its low mechanical strength. In this study, polyamide 6 (PA6) was blended with PS to improve the mechanical strength of PS, by means of a multi-jet electrospinning. Content ratio of the blend web was measured by chemical immersion test and confocal microscopy analysis. Fiber content was in accordance with the number of syringes used for PS and PA6 respectively. The effects of content ratio on the web morphology, thermal resistance, tensile behavior, air and water vapor permeability, and surface hydrophilicity were investigated. The influence of environmental humidity during electrospinning process on three dimensional (3D) web structure was also reported. PS web produced from higher humidity had more pores and corrugations at the surface. The increased surface roughness and porosity led to the increased hydrophobicity and thermal resistance. Though the blending of PA6 with PS enhanced the mechanical strength, the added PA6 decreased air/water vapor permeability and thermal resistance. The lowered thermal resistance by the addition of PA6 was mainly attributed to higher thermal conductivity of PA6 material and lowered air content with PA6 fibers

Parent-Reported Symptoms of Attention Deficit Hyperactivity Disorder in Children with Intermittent Exotropia before and after Strabismus Surgery

∙ The authors have no financial conflicts of interest. © Copyright: Yonsei University College of Medicine 2012 This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial Licens

Inscribing or Circumscribing a Histogon to a Convex Polygon

We consider two optimization problems of approximating a convex polygon, one by a largest inscribed histogon and the other by a smallest circumscribed histogon. An axis-aligned histogon is an axis-aligned rectilinear polygon such that every horizontal edge has an integer length. A histogon of orientation ? is a copy of an axis-aligned histogon rotated by ? in counterclockwise direction. The goal is to find a largest inscribed histogon and a smallest circumscribed histogon over all orientations in [0,?). Depending on whether the horizontal width of a histogon is predetermined or not, we consider several different versions of the problem and present exact algorithms. These optimization problems belong to shape analysis, classification, and simplification, and they have applications in various cost-optimization problems

Prevalence of health-related quality of life (HRQOL) in Asian Americans

Objectives To report the prevalence of Health Related Quality of Life (HRQOL) in foreign-born Asian Americans (AA) and to compare this with the general AA from 2010 BRFSS data. To examine the influential factors associated with HRQOL-4 including English proficiency, perceived racial discrimination, smoking, alcohol use, and sociodemographics. Background Quality of life (QOL) represents individuals’ subjective perception of multidimensional aspects of life including physical, psychological, social and spiritual aspects. HRQOL represents the physical and mental health domain of QOL. Centers for Disease Control and Prevention (CDC) has been measuring HRQOL to capture people’s overall perceptions about their health; HRQOL has become an important component of health surveillance (U.S. DHHS, 2000). While acculturation and racial discrimination have been negatively associated to the number of chronic health conditions and well-being of AA, their influence on HRQOL has not been studied. Public surveillance study has typically considered Asian Americans as a single group and little is known about how HRQOL and health-related risk factors vary among foreign-born Asian Americans including Chinese-, Korean-, and Vietnamese- Americans. Poster presented at APHA in Chicago Illinois.https://jdc.jefferson.edu/medoncposters/1000/thumbnail.jp

Unusual extraction treatment in Class II division 1 using C-orthodontic mini-implants.

AbstractThis paper describes the treatment of a female patient, aged 23 years and 5 months, with a Class II division 1 malocclusion, who showed severe anterior protrusion and lower anterior crowding. Specially-designed orthodontic mini-implants were placed bilaterally in the interdental space between both the upper and the lower posterior teeth. Both lower first molars showed severe apical lesions. Therefore, the treatment plan consisted of extraction of both upper first premolars and lower first molars, en masse retraction of the upper six anterior teeth, lower anterior alignment, and protraction of all the lower molars. C-implants® were used as substitutes for maxillary posterior anchorage teeth during anterior retraction and as hooks for mandibular molar protraction. The correct overbite and overjet were obtained by intruding and retracting the upper six anterior teeth into their proper positions. The dentition was detailed using conventional orthodontic appliances. The upper C-implants contributed to an improvement in facial balance, and the lower C-implants made it possible to protract the lower second and third molars with less effect on the axis of the lower anterior teeth. The active treatment period was 29 months and the patient's teeth continued to be stable 11 months after debonding

Treatment of Branch Retinal Artery Occlusion With Transluminal Nd:YAG Laser Embolysis

The purpose of this paper was to report a successful treatment of transluminal Nd:YAG laser embolysis (NYE) for branch retinal artery occlusion (BRAO) with visible emboli. Two patients with acute, severe vision loss secondary to a branch retinal artery occlusion with visible emboli in one eye underwent NYE. A complete ocular examination was performed which included biomicroscopy of the posterior pole of the retina, intraocular pressure measurement, fundus color photographs, and fluorescein angiography (FA). After the NYE, the two patients showed dramatic improvements in best-corrected visual acuity, as well as, immediate and dramatic restorations in flow past the obstructed arteriole in FA. NYE is a treatment modality to be considered in patients with BRAO who present acutely with severe vision loss and a visible embolus

Pig-to-Nonhuman Primate (NHP) Naked Islet Xenotransplantation

Islet transplantation is an established therapy for selected type 1 diabetes (T1D) patients with severe hypoglycemic unawareness and glycemic liability despite of insulin treatment. However, the donor organ is limited. Porcine islets are the best alternative source to overcome this limitation, and pig-to-nonhuman primate (NHP) naked islet xenotransplantation studies are being performed worldwide. Several studies including our own have presented successful proof-of-concept results based on immunosuppression regimen including the anti-CD154 monoclonal antibody. Particularly, long-term control of diabetes by adult porcine islet transplantation has been demonstrated in five consecutive monkeys, and the longest survival was ~1000 days after transplantation. Currently, pig-to-NHP islet xenotransplantation based on clinically applicable immunosuppression regimen is being pursued. In this chapter, we will describe all the procedures of pig-to-NHP naked islet xenotransplantation: (1) the porcine islet isolation from designated pathogen-free (DPF) miniature pigs, (2) diabetes induction in monkeys, (3) transplantation procedure via the portal vein, (4) immune monitoring comprising humoral and cellular immunity after porcine islet transplantation, and finally (5) liver biopsy and subsequent immunohistochemical procedure in detail

Tool to visualize and evaluate operator proficiency in laser hair-removal treatments

BACKGROUND: The uniform delivery of laser energy is particularly important for safe and effective laser hair removal (LHR) treatment. Although it is necessary to quantitatively assess the spatial distribution of the delivered laser, laser spots are difficult to trace owing to a lack of visual cues. This study proposes a novel preclinic tool to evaluate operator proficiency in LHR treatment and applies this tool to train novice operators and compare two different treatment techniques (sliding versus spot-by-spot). METHODS: A simulation bed is constructed to visualize the irradiated laser spots. Six novice operators are recruited to perform four sessions of simulation while changing the treatment techniques and the presence of feedback (sliding without feedback, sliding with feedback, spot-by-spot without feedback, and spot-by-spot with feedback). Laser distribution maps (LDMs) are reconstructed through a series of images processed from the recorded video for each simulation session. Then, an experienced dermatologist classifies the collected LDMs into three different performance groups, which are quantitatively analyzed in terms of four performance indices. RESULTS: The performance groups are characterized by using a combination of four proposed indices. The best-performing group exhibited the lowest amount of randomness in laser delivery and accurate estimation of mean spot distances. The training was only effective in the sliding treatment technique. After the training, omission errors decreased by 6.32% and better estimation of the mean spot distance of the actual size of the laser-emitting window was achieved. Gels required operators to be trained when the spot-by-spot technique was used, and imposed difficulties in maintaining regular laser delivery when the sliding technique was used. CONCLUSIONS: Because the proposed system is simple and highly affordable, it is expected to benefit many operators in clinics to train and maintain skilled performance in LHR treatment, which will eventually lead to accomplishing a uniform laser delivery for safe and effective LHR treatment

Allelic and Haplotypic Diversity of HLA-A, -B, -C, and-DRB1 Genes in Koreans Defined by High-resolution DNA Typing

배경 : HLA 형별은 혈청학적 수준(generic level)에서도 다형성이 심하지만 대립유전자 수준에서는 더욱 심한 다형성을 보이고 인종 간에 큰 차이를 나타내는 것으로 알려졌다. 본 연구에서는 고해상도 DNA 검사법을 이용하여 한국인에서 HLA대립유전자 형별과 일배체형의 종류 및 빈도를 알아보고자 하였다. 방법 : 건강한 한국인 474명을 대상으로 HLA-A, -B, -C, -DRB1 유전자에 대해 두 단계의 검사로 대립유전자(4자리수) 형별 분석을 실시하였다. 1단계로 혈청학적 수준의 형별검사를 혈청학적 검사법이나 sequence-specific oligonucleotide(PCR-SSO) 방법으로 시행하였고, 그 다음 단계로 대립유전자 형별검사를 class I은 exon 2와 exon3, DRB1은 exon 2에 대해 single-strand conformation polymorphism (PCR-SSCP) 또는 직접염기서열분석법을 이용하여 실시하였다. HLA 대립 유전자의 유전자 빈도, 일배체형 빈도, 연쇄불평형 값은 maximum likelihood 원리에 근거한 제11차 국제조직적합성워크숍 컴퓨터 프로그램을 이용하여 산출하였다. 결과 : 한국인에서 검출된 HLA-A, -B, -C, DRB1 대립유전자 형별은 각각 21, 40, 22, 29종이었다. 이 중에 유전자 빈도 10% 이상을 보인 대립유전자 형별(빈도순 나열)은 A*02:01, A*24:02, A*33:03; B*51:01; C*01:02, C*03:03; RB1*09:01등이었다. HLA 일배체형의 분석 결과 0.5% 이상의 빈도를 나타내는 2-유전자좌 일배체형은 A-C 44종, B-C 42종, A-B 51종, B-DRB1 52종이었고, 3-유전자좌 일배체형은 A-C-B 42종, A-B-DRB1 34종이었다. 한국인에서 빈도 1% 이상의 A-B-DR 일배체형은 13종으로, 전체 일배체형의 26.0%를 차지하였고, 2% 이상으로 가장 흔한 A-B-DR 일배체형은 A*33:03-B*44:03-DRB1*13:02 (3.7%), A*33:03-B*44:03-DRB1*07:01 (3.0%), A*33:03-B*58:01-DRB1*13:02 (3.0%), A*24:02-B*07:02-DRB1*01:01 (2.8%), A*30:01-B*13:02-DRB1* 07:01 (2.3%), A*11:01-B*15:01-DRB1*04:06 (2.2%) 등 6종이었다. 결론 : 본 연구를 통해 한국인의 대립유전자 수준의 HLA 형별과 HLA 일배체형 빈도에 대한 자료를 제시하였으며, 본 연구의 결과는 한국인에서 장기이식, 질환연관성 연구, 인류유전학적 연구 등에서 중요한 기초자료로 이용될 수 있을 것으로 기대된다. Background : In this study, we used high-resolution DNA typing to investigate the distribution of HLA alleles and haplotypes in Koreans. Methods : HLA-A, -B, -C, and -DRB1 alleles were genotyped at the allelic (4-digit) level in 474 healthy Koreans. HLA genotyping was performed in two steps. Initially, serologic typing or generic-level DNA typing was performed using the FOR-sequence-specific oligonucleotide method, and then allelic DNA typing (exons 2 and 3 for class I, and exon 2 for DRB1) was carried out using the FOR-single-strand conformation polymorphism method or sequence-based typing. HLA allele and haplotype frequencies and linkage disequilibrium values were calculated by the maximum likelihood method using a computer program developed for the 11th International Histocompatibility Workshop. Results : A total of 21 HLA-A, 40 HLA-B, 22 HLA-C, and 29 HLA-DRB1 alleles were found in Koreans. The most frequent alleles in each locus with frequencies of >= 10% were, in decreasing order of frequency, as follows: A star 24:02, A star 02:01, A(star)33:03; B(star)51:01; C(star)01:02, C(star)03:03; and DRB1(star)09:01. The numbers of two- and three-locus haplotypes with frequencies of >0.5% were as follows: 44 A-C, 42 B-C, 51 A-B, 52 B-DRB1, 42 A-C-B, and 34 A-B-DRB1. Thirteen A-B-DRB1 haplotypes with frequencies of >= 1.0% comprised 26.0% of the total haplotypes. The six most common haplotypes were as follows: A(star)33:03-B(star)44:03-DRB1(star)3:02 (3.7%), A(star)33:03-B(star)44:03-DRB1(star)07:01 (3.0%), A(star)33:03-B(star)58: 01-DRB1(star)13:02 (3.0%), A(star)24:02-B(star)07:02-DRB1(star)01:01 (2.8%), A(star)30:01-B(star)13:02-DRB1(star)07:01 (2.3%), and A(star)11:01-B(star)15:01-DR81(star)04:06 (2.2%). Conclusions : The information obtained in this study can be used as basic data for Koreans in the fields of organ transplantation, disease association, and anthropologic studies. 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