• Title/Summary/Keyword: history of chemistry

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Analysis of 2009 Revised Chemistry I Textbooks Based on STEAM Aspect (STEAM 관점에서 2009 개정 화학 I 교과서 분석)

  • Bok, Juri;Jang, Nak Han
    • Journal of Science Education
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    • v.36 no.2
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    • pp.381-393
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    • 2012
  • This study was analyzed that what kind of elements for STEAM, except scientific commonsense, are contained in 2009 revised chemistry textbooks I for high school students. So first, elements of STEAM in textbooks were examined by following three sections; by publishing company, each unit and area of textbook. For reference, new sub-elements of STEAM were set because existing elements of STEAM is incongruent with current textbooks. As a result, most chemistry textbooks included elements of STEAM properly for inter-related learning with the other fields. Every textbook had its unique learning methods for utilizing elements of STEAM and they were unified as one way. Depending on textbooks, learning methods were little bit different from the others. Also, detailed elements of STEAM contained in textbooks were classified just 14 types. And they were even focused on a few elements according to sort of textbook. Thus, it seemed that there was a certain limitation of current education of STEAM in chemistry Field. By the unit, according to the curriculum, contained elements of STEAM were different. Almost all elements of STEAM were located in I section. Consequently, it is difficult to include elements of STEAM if mathematics or history were not existed in curriculum. Lastly, by the area, most of all elements of STEAM were included in reference section. Almost all elements of STEAM were focused on art and culture. Thus, STEAM was used for utilization about chemical knowledge in substance. Otherwise, convergence training for approach method was not enough in chemical knowledge.

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Impact of Breed on the Fecal Microbiome of Dogs under the Same Dietary Condition

  • Reddy, Kondreddy Eswar;Kim, Hye-Ran;Jeong, Jin Young;So, Kyoung-Min;Lee, Seul;Ji, Sang Yun;Kim, Minji;Lee, Hyun-Jung;Lee, Sungdae;Kim, Ki-Hyun;Kim, Minseok
    • Journal of Microbiology and Biotechnology
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    • v.29 no.12
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    • pp.1947-1956
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    • 2019
  • The gut microbiome influences the health and well-being of dogs. However, little is known about the impact of breed on the fecal microbiome composition in dogs. Therefore, we aimed to investigate the differences in the fecal microbiome in three breeds of dog fed and housed under the same conditions, namely eight Maltese (8.0 ± 0.1 years), eight Miniature Schnauzer (8.0 ± 0.0 years), and nine Poodle dogs (8.0 ± 0.0 years). Fresh fecal samples were collected from the dogs and used to extract metagenomic DNA. The composition of the fecal microbiome was evaluated by 16S rRNA gene amplicon sequencing on the MiSeq platform. A total of 840,501 sequences were obtained from the 25 fecal samples and classified as Firmicutes (32.3-97.3% of the total sequences), Bacteroidetes (0.1-62.6%), Actinobacteria (0.2-14.7%), Fusobacteria (0.0-5.7%), and Proteobacteria (0.0-5.1%). The relative abundance of Firmicutes was significantly lower in the Maltese dog breed than that in the other two breeds, while that of Fusobacteria was significantly higher in the Maltese than in the Miniature Schnauzer breed. At the genus level, the relative abundance of Streptococcus, Fusobacterium, Turicibacter, Succinivibrio, and Anaerobiospirillum differed significantly among the three dog breeds. These genera had no correlation with age, diet, sex, body weight, vaccination history, or parasite protection history. Within a breed, some of these genera had a correlation with at least one blood chemistry value. This study indicates that the composition of the fecal microbiome in dogs is affected by breed.

Sick Sinus Syndrome (SSS) in a Maltese Dog Concurrent with Mitral Valve Endocardiosis (MVE) (말티즈견에서 발생한 Mitral Valve Endocardiosis (MVE)를 동반한 Sick Sinus Syndrome (SSS)에 대한 증례)

  • Park Chul;Jung Dong-in;Kim Ha-Jung;Kang Byeong-Teck;Kim Ju-Won;Lim Chae-Young;Yoo Jong-Hyun;Park Hee-Myung
    • Journal of Veterinary Clinics
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    • v.22 no.4
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    • pp.396-400
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    • 2005
  • A 13-year old, female Maltese dog was presented due to a five-month history of episodic syncope. A diagnosis of sick sinus syndrome (SSS) with mitral valve endocardiosis (MVE) was made based on history takings, physical and cardiac examination, complete blood count (CBC), serum chemistry profiles, radiography, electrocardiography (ECG), atropine response test, hormonal assay, and echocardiography. In this case, SSS was definitely diagnosed by evaluation of ECG recording following atropine administration. Clinical signs were improved with medical management of theophylline (THEOLAN, KunWha Pharm, Seoul, Korea, 20 mg/kg, PO, BID). After 10 more month survival, the dog, died of respiratory distress and shock during the operation of abdominal mass removal in local animal hospital. Unfortunately, we were not able to perform necropsy after death due to owner's decline. This case demonstrates that theophylline can be used in management oF dog with SSS.

On the Chemical Properties of Nursery Soil in Cultivation of Panax ginseng (인삼포상토(人蔘圃床土)의 화학적(化學的) 성상(性狀)에 관(關)한 연구(硏究))

  • Lim, Sun-Uk
    • Applied Biological Chemistry
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    • v.18 no.2
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    • pp.65-70
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    • 1975
  • The cultivation of ginseng plant (Panax ginseng C.A. Meyer) in Korea as an eminent medicinal herb may be traced far back in history. However, the practices in cultivation have not much improved in terms of efficiency and scientific farming. In the present study some experiments were undertaken for the search of the soil and nutrition conditions, because of the nutritional requirement of ginseng plant shaws quite unique compared with other crops. In both the seed bed and the field 'Yakto' has been traditionally employed or the prime source of nutrition of the crop. Yakto is a complex matter prepared from raw foliage of the broad-leaved trees as the main portion with the admixture of a variety of organic nitrogen source through fermentative processes. The composition of Yakto may be classified coarsely into the decomposed and undecomposed substances, the former being further fractionated according their solubilities, comprising also various colloidal matters whose composition and structure are yet to be known. The Yakto-fractions were subjected to analyze for search of its nature and coarse composition in terms of the distribution of nitrogen, contents of organic functional groups such as -COOH, phenolic-OH, alcholic-OH and methoxyl and hydrolysable sugars. Furthermore, absorption-spectra of each fraction were determined in visible and infrared region and compared the results each other.

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Thermal Properties and Molecular Weight Variations due to Thermal History in Segmented Polyurethane Copolymer Blends (세그먼트된 폴리우레탄 블렌드의 열이력에 따른 열적 성질과 분자량 변화)

  • Cha, Yoon-Jong;Park, Dae-Woon;Kim, Hak-Lim;Lee, Han-Sup;Mah, Souk II;Choe, Soonja
    • Applied Chemistry for Engineering
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    • v.10 no.1
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    • pp.35-40
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    • 1999
  • The variations of the glass transition, melting peaks, molecular weight and its distribution (polydispersity index: PI) due to the annealing temperature and time have been investigated using the thermoplastic segmented polyurethanes (TPUs) and its blends based on the contents of hard segment. The position of the melting peak and its magnitude have been increased with the annealing temperature and time. This may be arised from the rearrangement of the microdomain structure due to the long-range or short-range segmental motion, the order-disorder transition of non-crystalline microphase, the variation of the domain size or the degree of disorder of crystalline structure by given different thermal histories. The annealing temperature and time affected the molecular weights and polydispersity : the number and weight average molecular weights were increased, while the polydispersity index (PI) deceased at certain temperatures : for TPU-35 at $135^{\circ}C$, for TPU-44 at $170^{\circ}C$ and for TPU-53 at $180^{\circ}C$. The temperatures which give the variations in molecular weights and in PIs are consistent with the annealing temperatures of which $T_3$ solely exists for each sample. Thus it is suggested that the chain dissosiation and recombination simultaneously occur at the above mentioned temperature for each sample.

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Mating Systems and Flowering Characteristics of Megaleranthis saniculifolia Ohwi in a Subalpine Zone of Sobaeksan National Park (소백산국립공원 아고산지역 모데미풀 (Megaleranthis saniculifolia Ohwi, Ranunculaceae)의 교배체제와 개화특성)

  • Lee, Hakbong;Lee, Hyeseon;Kang, Hyesoon
    • Korean Journal of Ecology and Environment
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    • v.50 no.1
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    • pp.116-125
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    • 2017
  • Alpine plants with a scarcity of pollinators in harsh environments have been believed to undergo selfing for reproductive assurance; however, contradictory evidence is also available. Snowmelt regimes in alpine areas function to change life history characteristics of alpine plants such as flowering time and duration; yet the effects of snowmelt regimes have never been tested in alpine plants in Korea. This study was conducted to investigate the dichogamy, mating systems, and flowering characteristics of Megaleranthis saniculifolia populations [early and late snowmelt plots (ESP and LSP, respectively)] in a subalpine area of Sobaeksan Mountain in Korea. M. saniculifolia exhibited incomplete protogyny in that despite early maturation of pistils, maturation times of pistils and stamens within flowers were partly overlapped. Control and hand-outcrossing treatments produced significantly higher number of follicles and seeds per flower than autonomous and hand-selfing treatments. Based on the aggregate fruit set, the auto-fertility index (AI) and self-compatibility index (SI) were 0.33 and 0.50, respectively. Snowmelt occurred 10 days earlier in ESP than in LSP, thereby ESP and LSP showed distinct differences with regard to flower longevity and season, but showing no difference in peak flowering dates. We concluded that M. saniculifolia is an incomplete protogynous and largely outcrossing plant requiring pollinator service. Temporal variation in snowmelt time and subsequent changes in flowering characteristics under climate change may further threaten the population persistence of M. saniculifolia which has already been designated as endangered species in Korea.

Retroperitoneal Suppurative Fistula Caused by Remnant Suture Material in a Poodle Dog

  • Kim, Keunyung;Lee, Chaeyeong;Kim, Minyeon;Choi, Hyeonjong;Hong, Jeongho;Kim, Hyoyeon;Park, Hyojin;Kim, Na-hyun;Lee, Dongbin;Lee, Jae-Hoon
    • Journal of Veterinary Clinics
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    • v.38 no.6
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    • pp.285-289
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    • 2021
  • An eight-year-old, 3.4 kg, spayed female poodle dog was referred to Gyeongsang National University Animal Medical Center with obstinate bilateral retroperitoneal subcutaneous abscess. The medical history revealed ovariohysterectomy (OHE), lipoma, and mammary gland tumor excision performed two years ago. The dog presented with left retroperitoneal subcutaneous abscess discharge five months back and was treated by abscess drainage and antibiotics in a local veterinary hospital, but a relapse was reported on discontinuing antibiotics. On physical examination, the dog was febrile (40℃) and both retroperitoneal masses showed typical inflammatory reaction and purulent discharge. On serum chemistry analysis, hyperproteinemia, hyperglobulinemia, and elevated levels of C-reactive protein were observed. Cytologic examination showed degenerative neutrophils and phagocytic macrophages. Radiological examination revealed encapsulated hypoechoic subcutaneous masses in bilateral abdominal flank and the left flank mass was connected with the caudal pole of left kidney through fistula. Based on the diagnostic examination, exploratory celiotomy was recommended and left nephrectomy, and resection of bilateral masses were performed. During procedure, fistula between caudal pole of left kidney and left subcutaneous abscess was detected and suture material was identified. Resected tissue was histologically examined and diagnosed as suppurative abscess caused by the suture material. This case report describes chronic suppurative foreign body reaction including caudal pole of left kidney and bilateral retroperitoneal subcutaneous masses induced by the suture material used in OHE two years ago and the necessity of computed tomography examination to identify character of mass and extent of surgical resection.

Distinguishing the Effects of Environmental Stress and Forest Succession on Changes in the Forest Floor

  • Arthur, Mary A.;Ruth D. Yanai
    • The Korean Journal of Ecology
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    • v.23 no.2
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    • pp.83-88
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    • 2000
  • When interpreting change over time in forest ecosystems, distinguishing the effects of forest succession from the effects of environmental stress can be difficult. The result may be a simplistic interpretation. citing a specific successional or environmental cause of forest change when both types may be occurring. We present two case studies of changes in the forest floor in northern hardwoods. First, the belief that 50% of soil organic matter is lost in the first 20 years after logging was based on a study comparing northern hardwood stands of different ages. We resampled a series of 13 such stands after an interval of 15 years, and found that the young stands were not, in fact. losing organic matter as rapidly as predicted from the original chronosequence study. The pattern of higher organic matter content in the forest floors of older stands compared to young stands could be equally well explained by changes in logging practices over the last century as by the aging of the stand. The observed pattern of forest floor organic matter as a function of stand age was previously interpreted as a successional pattern, ignoring changes in treatment history. In the second case study, observed losses of base cations from the forest floor were attributed to cation depletion caused by acid rain and declining calcium deposition. We found that young stands were gaining base cations in the forest floor; losses of base cations were restricted to older stands. Differences in litter chemistry in stands of different ages may explain some of the pattern in cation gains and losses. In this case, the contribution of successional processes to cation loss had been overlooked in favor of environmental stress as the dominant mechanism behind the observed changes. Studies of environmental stress use repeated measures over time. but often don't consider stand age as a factor. Studies of successional change often assume that environmental factors remain constant. We were able to consider both forest succession and external factors because we repeatedly sampled stands of different ages.

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Prognostic Factors of Idiopathic Facial Palsy: A Retrospective Study

  • Park, Gi Nam;Jeong, Jeong Kyo;Kim, Eun Seok;Kim, Jung Ho;Kim, Young Il
    • Journal of Acupuncture Research
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    • v.34 no.3
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    • pp.23-38
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    • 2017
  • Objectives : The purpose of this study was to evaluate the clinical prognostic factors affecting facial palsy in 98 idiopathic facial palsy patients who were hospitalized and treated in 2015, using retrospective statistical analysis. Methods : We investigated patients with idiopathic facial nerve palsy, admitted to a Korean medical hospital in 2015, and examined patients' variables and therapeutic variables. For analysis of clinical data, an independent sample t-test, analysis of variance (ANOVA), and simple regression analysis were performed using IBM SPSS version 24.0. Results : 1. The initial degree of facial palsy showed statistical significance with age. The older the age, the more severe the initial palsy. 2. Following treatment degree of facial palsy was statistically significant with age, hypertension, and fasting blood sugar (FBS). The higher the value, the slower the recovery from facial palsy. There was a statistical significance with the number of treatments in a Korean medical hospital. The more frequent the treatment, the faster the facial palsy recovery. 3. Degree of facial palsy after 12 months was statistically significant with age, hypertension, diabetes, FBS, and the initial severity of facial palsy. The higher the value, the slower the facial palsy recovery. 4. Sex, left or right sided palsy, alcohol consumption, smoking, history of facial palsy, season of onset, total number of treatments and bio chemistry (BC), complete blood cell count (CBC), urinalysis (UA) factors had no statistical significance with prognosis of facial palsy. Conclusion : Age, season of onset, hypertension, diabetes, FBS, initial severity of facial palsy, and the number of treatments at a Korean medical hospital showed statistical significance. The number of treatments at the Korean medical hospital positively correlated with facial palsy prognosis, and the others variables showed a negative correlation with facial palsy prognosis.

Bradycardia after Dobutamine Administration in a Dog (Dobutamine 투여 후 발생한 개의 서맥 1례)

  • Jang, Min;Son, Won-Gyun;Hwang, Hyeshin;Jo, Sang-Min;Yi, Kang-Jae;Yoon, Junghee;Lee, Inhyung
    • Journal of Veterinary Clinics
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    • v.31 no.4
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    • pp.350-353
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    • 2014
  • A 13-year-old, castrated male, Shih Tzu dog with a history of acute ataxia was referred to veterinary medical teaching hospital and anesthetized for diagnostic magnetic resonance imaging of cervical intervertebral disk disease. After preanesthetic evaluation including physical examination, blood chemistry, radiography and ultrasound, the patient was premedicated with intravenous butorphanol (0.2 mg/kg). Anesthesia was induced by intravenous propofol (6 mg/kg) and maintained with isoflurane at 1.2 minimal alveolar concentrations. Because the mean arterial pressure (MAP) decreased from 70 to 58 mmHg at 70 minutes after induction, dobutamine was administered by constant rate infusion ($5{\mu}g/kg/min$) to treat hypotension. However MAP did not increase, and heart rate rapidly decreased from 100 to 55 beats per minute (bpm). To treat bradycardia, intravenous glycopyrrolate ($5{\mu}g/kg$) was administered, and heart rate increased to 165 bpm. After extubation of endotracheal tube, the patient showed normal recovery without any problems related to cardiovascular system. Unexpected dobutamine-induced bradycardia was considered as Bezold-Jarisch reflex. It is recommended that clinicians know and prepare the possibility of bradycardia during dobutamine therapy under general anesthesia.