• Title/Summary/Keyword: rare events

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An Active Temporal Rule Model on Temporal Database (시간지원 데이터베이스 상의 능동적 시간지원 규칙 모델)

  • Park, Jeong-Seok;Kim, Hyun-Chul;Ryu, Keun-Ho
    • Journal of Internet Computing and Services
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    • v.1 no.1
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    • pp.15-26
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    • 2000
  • To efficiently manage data varying over time and process event driven transactions, some of the various database applications recently emerged require database systems supporting both a temporal data model and active rule processing. There has been much progress in independent research on temporal databases and active databases, but studies on databases which support both functions, have been rare. In this paper, an active temporal rule model supporting both active rule processing and temporal data model is presented with its rule expression language. This active temporal rule model contributes to the active function extension of the temporal database, and to establishing the concept of data access events which refer temporal attributes of data in active rules.

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Statistical Properties of Flare Variability, Energy, and Frequency in Low-Mass Stars

  • Chang, Seo-Won;Byun, Yong-Ik
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.1
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    • pp.29.2-29.2
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    • 2011
  • Although stellar flares have a long history of observations, there are few concrete understanding about underlying physical processes and meaningful correlations with other stellar properties. Most of previous observations dealt with only a small number of sample stars, and therefore not sufficient to support generalized statistical studies. Based on one-month long MMT time-series observations of the open cluster M37, we monitored light variations of nearly 2,500 M-dwarf stars and successfully identified 606 flare events from 422 stars. This is a rare attempt to estimate true flare rates and properties among many stars of the same age and mass group. For each flare, we considered both observational and physical parameters including flare shape, duration before and after the peak, baseline magnitude before and after the peak, peak magnitudes, total energy and peak energy, etc. We find significant correlations between some of key parameters over a wide range of energy ($Er=10^{32}{\sim}10^{36}ergs$). For instance, regardless of stellar luminosities, the energy power spectrum of flares can be approximated by a power law (${\beta}=0.83-0.97$). This suggests that flares follow similar physical mechanisms for atmospheric heating and cooling among these low-mass stars. From this MMT data set, we derived an average flaring rate of $0.019 hr^{-1}$ among flare stars and $0.003 hr^{-1}$ for all M-dwarf candidates. We will report the details of our analysis and discuss physical implications.

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Neonatal Diabetes Mellitus Due to KCNJ11 (KIR6.2) Mutation Successfully Treated with Sulfonylurea

  • Jang, Sehun;Yang, Misun;Ahn, So Yoon;Sung, Se In;Chang, Yun Sil;Park, Won Soon
    • Neonatal Medicine
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    • v.28 no.2
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    • pp.94-98
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    • 2021
  • Neonatal diabetes mellitus (NDM) is a rare disease that occurs at less than 6 months of age and is presumably caused by a mutation in the gene that affects pancreatic beta-cell function. Approximately 80% of NDM cases reveal a known genetic mutation, and mutations in potassium inwardly rectifying channel subfamily J member 11 (KCNJ11) and ABCC8 affecting the pancreatic beta-cell adenosine triphosphate-sensitive potassium channel may be treated with oral sulfonylurea. Early recognition of mutations in KCNJ11 and ABCC8 is important because early administration of sulfonylurea can not only control blood glucose levels but also improve neurodevelopmental outcomes. In the present study, we report a case of NDM that initially presented as diabetic ketoacidosis at the age of 1 month, accompanied by seizures during hospitalization. After confirmation of the KCNJ11 gene mutation (c.989A>C), we started administering oral sulfonylurea (glimepiride) at the age of 2 months. After gradually increasing the dosage of glimepiride, insulin was discontinued at the age of 3 months. To date, the infant's blood glucose levels have been well controlled without significant hypoglycemic events. No further episodes of seizures have occurred, and his developmental status is favorable.

Gastrulation : Current Concepts and Implications for Spinal Malformations

  • Thompson, Dominic Nolan Paul
    • Journal of Korean Neurosurgical Society
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    • v.64 no.3
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    • pp.329-339
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    • 2021
  • It has been recognised for over a century that the events of gastrulation are fundamental in determining, not only the development of the neuraxis but the organisation of the entire primitive embryo. Until recently our understanding of gastrulation was based on detailed histological analysis in animal models and relatively rare human tissue preparations from aborted fetuses. Such studies resulted in a model of gastrulation that neurosurgeons have subsequently used as a means of trying to explain some of the congenital anomalies of caudal spinal cord and vertebral development that present in paediatric neurosurgical practice. Recent advances in developmental biology, in particular cellular biology and molecular genetics have offered new insights into very early development. Understanding the processes that underlie cellular interactions, gene expression and activation/inhibition of signalling pathways has changed the way embryologists view gastrulation and this has led to a shift in emphasis from the 'descriptive and morphological' to the 'mechanistic and functional'. Unfortunately, thus far it has proved difficult to translate this improved knowledge of normal development, typically derived from non-human models, into an understanding of the mechanisms underlying human malformations such as the spinal dysraphisms and anomalies of caudal development. A paediatric neurosurgeons perspective of current concepts in gastrulation is presented along with a critical review of the current hypotheses of human malformations that have been attributed to disorders of this stage of embryogenesis.

Triglyceride-Rich Lipoproteins and Novel Targets for Anti-atherosclerotic Therapy

  • Reiner, Zeljko
    • Korean Circulation Journal
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    • v.48 no.12
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    • pp.1097-1119
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    • 2018
  • Although elevated serum low-density lipoprotein-cholesterol (LDL-C) is without any doubts accepted as an important risk factor for cardiovascular disease (CVD), the role of elevated triglycerides (TGs)-rich lipoproteins as an independent risk factor has until recently been quite controversial. Recent data strongly suggest that elevated TG-rich lipoproteins are an independent risk factor for CVD and that therapeutic targeting of them could possibly provide further benefit in reducing CVD morbidity, events and mortality, apart from LDL-C lowering. Today elevated TGs are treated with lifestyle interventions, and with fibrates which could be combined with omega-3 fatty acids. There are also some new drugs. Volanesorsen, is an antisense oligonucleotid that inhibits the production of the Apo C-III which is crucial in regulating TGs metabolism because it inhibits lipoprotein lipase (LPL) and hepatic lipase activity but also hepatic uptake of TGs-rich particles. Evinacumab is a monoclonal antibody against angiopoietin-like protein 3 (ANGPTL3) and it seems that it can substantially lower elevated TGs levels because ANGPTL3 also regulates TGs metabolism. Pemafibrate is a selective peroxisome proliferator-activated receptor alpha modulator which also decreases TGs, and improves other lipid parameters. It seems that it also has some other possible antiatherogenic effects. Alipogene tiparvovec is a nonreplicating adeno-associated viral vector that delivers copies of the LPL gene to muscle tissue which accelerates the clearance of TG-rich lipoproteins thus decreasing extremely high TGs levels. Pradigastat is a novel diacylglycerol acyltransferase 1 inhibitor which substantially reduces extremely high TGs levels and appears to be promising in treatment of the rare familial chylomicronemia syndrome.

Carotid Artery Disease in Duplex Sonography: 3 Cases (이중초음파에서 관찰된 목동맥 질환: 3례)

  • Han, Minho;Choi, Junghye;Seo, Gang Sik;Nam, Hyo Suk
    • Korean Journal of Clinical Laboratory Science
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    • v.51 no.1
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    • pp.114-118
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    • 2019
  • Duplex sonography has been used to non-invasively diagnose carotid artery disease and to follow up patients with this disease. In carotid artery disease, carotid mobile thrombus and dissection are rarely detected by duplex sonography in patients with cerebrovascular events. In particular, carotid dissection occurs when a small tear forms in the tunica intima and makes 2 lumens in the carotid artery, including true and false lumens. This study reports 3 rare cases of carotid mobile thrombus, spontaneous carotid dissection, and carotid dissection in Takayasu arteritis.

Implementation of contextualized, emergency management cognitive aids in a periodontics clinic

  • Siemens, Mikaela J.;Rice, Andi N.;Jensen, Trenton F.;Simmons (Muckler), Virginia C.
    • Journal of Dental Anesthesia and Pain Medicine
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    • v.21 no.3
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    • pp.227-236
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    • 2021
  • Background: Emergencies in outpatient clinics are rare. However, potentially catastrophic events can be challenging to manage due to a variety of factors, including limited equipment and staff. The purpose of this quality improvement project was to improve the staff knowledge and familiarity with critical performance elements for emergencies encountered in the setting of a periodontics clinic. Methods: Emergency cognitive aids tailored to the clinic's resources were created for anaphylaxis, airway obstruction, and sublingual hemorrhage. The project pre-post-test repeated measures design evaluated the effectiveness of cognitive aids using a combination of hands-on simulation, written knowledge assessments, and self-efficacy surveys. Training sessions and simulations were provided to the clinic's existing care teams made up of a periodontist and two dental assistants with an anesthetist who was present for simulations involving sedation. Due to the small sample size (N = 14) and non-normal distribution, all metrics were evaluated using non-parametric statistics. Results: Significant improvements were found in knowledge assessment (-2.310, P = 0.021) and self-efficacy (-2.486, P = 0.013) scores when retention after a training session before and after the introduction of cognitive aid was compared. The mean simulation scores and times improved steadily or reached maximum scores during the project progression. Conclusion: Training sessions before and after cognitive aid introduction were effective in improving knowledge, self-efficacy, and simulation performance. Future projects should focus on validating the process for creating contextualized cognitive aids and evaluating the effectiveness of these cognitive aids in larger samples.

Concise Clinical Review of Hematologic Toxicity of Linezolid in Multidrug-Resistant and Extensively Drug-Resistant Tuberculosis: Role of Mitochondria

  • Oehadian, Amaylia;Santoso, Prayudi;Menzies, Dick;Ruslami, Rovina
    • Tuberculosis and Respiratory Diseases
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    • v.85 no.2
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    • pp.111-121
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    • 2022
  • Multidrug-resistant tuberculosis (MDR-TB) is caused by an organism that is resistant to both rifampicin and isoniazid. Extensively drug-resistant TB, a rare type of MDR-TB, is caused by an organism that is resistant to quinolone and one of group A TB drugs (i.e., linezolid and bedaquiline). In 2018, the World Health Organization revised the groupings of TB medicines and reclassified linezolid as a group A drug for the treatment of MDR-TB. Linezolid is a synthetic antimicrobial agent in the oxazolidinone class. Although linezolid has a good efficacy, it can cause substantial adverse events, especially hematologic toxicity. In both TB infection and linezolid mechanism of action, mitochondrial dysfunction plays an important role. In this concise review, characteristics of linezolid as an anti-TB drug are summarized, including its efficacy, pathogenesis of hematologic toxicity highlighting mitochondrial dysfunction, and the monitoring and management of hematologic toxicity.

Recovery of Acute Ophthalmoplegia after Hyaluronic Acid Filler Injections to the Temples: A Case Report and Review of the Literature

  • Fatemeh-sadat Tabatabaei;Amirali Azimi;Seyyed Shahabeddin Tabatabaei;Hossein Pakdaman
    • Archives of Plastic Surgery
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    • v.50 no.2
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    • pp.148-152
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    • 2023
  • Soft tissue filler injection is the second most common nonsurgical cosmetic procedure. Despite the safety of fillers, as use has grown, so has the number of patients affected by adverse events. Ophthalmoplegia following cosmetic filler injection is a rare complication, mostly occurring after injection to the glabella, nasolabial fold, periorbital, and lateral nasal site. In all cases where ophthalmoplegia has been reported following fillers, patients have simultaneously experienced vision loss and other ocular symptoms. We report a case of isolated acute ophthalmoplegia following hyaluronic acid injection solely in the temple region. A 40-year-old woman, 3 hours after the procedure, presented to our hospital with left eye ophthalmoplegia, ptosis, and hypotropia. Treatment started with hyaluronidase, steroids, and anticoagulants. After 4 weeks, left eye ophthalmoplegia remained unchanged, and through a 10-week follow-up, all left ocular movements improved, and only mild hypotropia and ptosis persisted. This case report shows that ophthalmoplegia may also happen with temple region filler injections. We also review available prevention techniques and treatments to avoid such complications when performing soft tissue fillers for gaunt appearance correction.

Ingestion and surgical retrieval of an endodontic file: a case report

  • Devon Marta Ptak;Elinor Alon;Robert Bruce Amato;Julia Tassinari;Adrian Velasquez
    • Restorative Dentistry and Endodontics
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    • v.48 no.4
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    • pp.32.1-32.8
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    • 2023
  • Ingestions and aspirations of foreign bodies are rare, but do occasionally occur during dental treatment. Although reports exist, few include photos demonstrating the extensive surgical intervention that may be necessary to manage such events. Perhaps this lack of visualization, and associated lack of awareness, is one of the reasons some clinicians still provide nonsurgical root canal therapy (NSRCT) without a rubber dam. This case report outlines the medical treatment of a 30-year-old male who initially presented to a general dentist's office (not associated with the authors) for NSRCT of their mandibular right first molar. A rubber dam was not used for this procedure, during which the accidental ingestion of an endodontic K-file occurred. The patient was subsequently hospitalized for evaluation and treatment, consisting of numerous imaging studies, endoscopic evaluation, and surgical removal of the file from his small intestine. The ingestion of foreign bodies, and the associated complications, can be reduced through the routine use of a rubber dam, which is considered the standard of care for NSRCT. This case graphically illustrates the potential consequences associated with deviating from the standard of care and should remind clinicians that a rubber dam is necessary for all cases of NSRCT.