• Title/Summary/Keyword: transition rate

Search Result 1,275, Processing Time 0.026 seconds

Successful Transition from Pediatric to Adult Care in Inflammatory Bowel Disease: What is the Key?

  • Kim, Jeongseok;Ye, Byong Duk
    • Pediatric Gastroenterology, Hepatology & Nutrition
    • /
    • v.22 no.1
    • /
    • pp.28-40
    • /
    • 2019
  • The incidence of pediatric-onset inflammatory bowel disease (IBD) is on the rise, accounting for up to 25% of IBD cases. Pediatric IBD often has extensive bowel involvement with aggressive and rapidly progressing behavior compared to adult IBD. Because IBD has a high morbidity rate and can have a lifelong impact, successful transition from pediatric to adult care is important to maintain the continuity of care. Furthermore, successful transition facilitates appropriate development and psychosocial well-being among patients, as well as comprehensive and harmonious healthcare delivery amongst stakeholders. However, there are various obstacles related to patients, family, providers, and organizations that interfere with successful transition. Successful transition requires a flexible and tailored plan that is made according to the patient's developmental abilities and situation. This plan should be established through periodic interviews with the patient and family and through close collaboration with other care providers. Through a stepwise approach to the transition process, patients' knowledge and self-management skills can be improved. After preparation for the transition is completed and the obstacles are overcome, patients can be gradually moved to adult care. Finally, successful transition can increase patients' adherence to therapy, maintain the appropriate health status, improve patients' self-management, and promote self-reliance among patients.

Kinetic and Molecular Orbital Stuides on the Reaction of 5-nitrofurfural Hydrazone Formation

  • Lee, Kyung-Hee;Jee, Jong-Gi
    • Bulletin of the Korean Chemical Society
    • /
    • v.6 no.5
    • /
    • pp.280-284
    • /
    • 1985
  • Kinetic measurements of the 5-nitrofurfural-hydrazine reaction in various pH ranges of aquous solution were carried out by ultraviolet spectrophotometry at $25^{\circ},\;35^{\circ}\;and\;45^{\circ}C$. The observed rate of the reaction varies with the change in pH, which gives characteristic "bell-type" rate acidity profile. The maximum rate is shown in the vicinity of pH 4. This reaction procceds with rate-determining attack of hydrazine on the 5-nitrofurfural at low pH and undergoes a change in rate-determining step to dehydration of the addition intermediate as pH increases. The reaction has a "reactant-like transition state" which precedes intermediate in low pH and "product-like transition state" which follows it in neutral pH. The geometry of 5-nitrofurfural-hydrazine intermediate was estimated with PCILO method associated with CNDO/2 scheme.

Synthesis of Multi-component Olivine by a Novel Mixed Transition Metal Oxalate Coprecipitation Method and Electrochemical Characterization

  • Park, Yeong-Uk;Kim, Jong-Sun;Gwon, Hyeok-Jo;Seo, Dong-Hwa;Kim, Seong-Uk;Hong, Ji-Hyeon;Gang, Gi-Seok
    • Proceedings of the Materials Research Society of Korea Conference
    • /
    • 2010.05a
    • /
    • pp.37.1-37.1
    • /
    • 2010
  • The multi-component olivine cathode material, $LiMn_{1/3}Fe_{1/3}Co_{1/3}PO_4$, was prepared via a novel coprecipitation method of the mixed transition metal oxalate, $Mn_{1/3}Fe_{1/3}Co_{1/3}(C_2O_4){\cdot}2H_2O$. The stoichiometric ratio and distribution of transition metals in the oxalate, therefore, in the olivine product, was affected sensitively by the environments in the coprecipitation process, while they are the important factors in determining the electrochemical property of electrode materials with multiple transition metals. The effect of the pH, atmosphere, temperature, and aging time was investigated thoroughly with respect to the atomic ratio of transition metals, phase purity, and morphology of the mixed transition metal oxalate. The electrochemical activity of each transition metal in the olivine synthesized through this method clearly was enhanced as indicated in the cyclic voltammetry (CV) and galvanostatic charge/discharge measurement. Three distinctive contributions from Mn, Fe, and Co redox couples were detected reversibly in multiple charge and discharge processes. The first discharge capacity at the C/5 rate was $140.5\;mAh\;g^{-1}$ with good cycle retention. The rate capability test showed that the high capacity still is retained even at the 4C and 6C rates with 102 and $81\;mAh\;g^{-1}$, respectively.

  • PDF

Comparison between Parametric and Semi-parametric Cox Models in Modeling Transition Rates of a Multi-state Model: Application in Patients with Gastric Cancer Undergoing Surgery at the Iran Cancer Institute

  • Zare, Ali;Mahmoodi, Mahmood;Mohammad, Kazem;Zeraati, Hojjat;Hosseini, Mostafa;Naieni, Kourosh Holakouie
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.11
    • /
    • pp.6751-6755
    • /
    • 2013
  • Background: Research on cancers with a high rate of mortality such as those occurring in the stomach requires using models which can provide a closer examination of disease processes and provide researchers with more accurate data. Various models have been designed based on this issue and the present study aimed at evaluating such models. Materials and Methods: Data from 330 patients with gastric cancer undergoing surgery at Iran Cancer Institute from 1995 to 1999 were analyzed. Cox-Snell Residuals and Akaike Information Criterion were used to compare parametric and semi-parametric Cox models in modeling transition rates among different states of a multi-state model. R 2.15.1 software was used for all data analyses. Results: Analysis of Cox-Snell Residuals and Akaike Information Criterion for all probable transitions among different states revealed that parametric models represented a better fitness. Log-logistic, Gompertz and Log-normal models were good choices for modeling transition rate for relapse hazard (state $1{\rightarrow}state$ 2), death hazard without a relapse (state $1{\rightarrow}state$ 3) and death hazard with a relapse (state $2{\rightarrow}state$ 3), respectively. Conclusions: Although the semi-parametric Cox model is often used by most cancer researchers in modeling transition rates of multistate models, parametric models in similar situations- as they do not need proportional hazards assumption and consider a specific statistical distribution for time to occurrence of next state in case this assumption is not made - are more credible alternatives.

The Low Probability of Intercept RADAR Waveform Based on Random Phase and Code Rate Transition for Doppler Tolerance Improvement (도플러 특성 개선을 위한 랜덤 위상 및 부호율 천이 기반 저피탐 레이다 파형)

  • Lee, Ki-Woong;Lee, Woo-Kyung
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.26 no.11
    • /
    • pp.999-1011
    • /
    • 2015
  • In modern electronic warfare, RADAR is under constant threat of ECM(Electronic Counter Measures) signals from nearby jammers. The conventional linear frequency modulated(Linear-FM) waveform is easy to be intercepted to estimate its signal parameters due to its periodical phase transition. Recently, APCN(Advanced Pulse Compression Noise) waveform using random amplitude and phase transition was proposed for LPI(Low probability of Intercept). But random phase code signals such as APCN waveform tend to be sensitive to Doppler frequency shift and result in performance degradation during moving target detection. In this paper, random phase and code rate transition based radar waveform(RPCR) is proposed for Doppler tolerance improvement. Time frequency analysis is carried out through ambiguity analysis to validate the improved Doppler tolerance of RPCR waveform. As a means to measure the vulnerability of the proposed RPCR waveform against LPI, WHT(Wigner-Hough Transform) is adopted to analyze and estimate signal parameters for ECCM(Electronic Counter Counter Measures) application.

Regional Demographic Transition in Developing Countries (개발도상국에서의 출산력 변천 추이)

  • Chung, Sung-Ho
    • Korea journal of population studies
    • /
    • v.28 no.2
    • /
    • pp.183-203
    • /
    • 2005
  • Over the past four decades reproductive behavior has changed rapidly in much of the developing countries. The average total fertility rate has fallen by half from six or more to near three today. Between 1960 and 2000 the largest fertility decline occurred in Asia and Latin America. The mortality rate has decreased in most developing countries. The purpose of this study is to review the pattern of demographic transition in developing countries. At first, this study focuses on the regional fertility transition. In Africa, the total fertility rate has decreased from 6.59 to 4.85 between 1960 and 2000. However, the rate has rapidly fallen from 5.76 to 2.34 in East Asia. The same pattern is found in Latin America. The mortality rate has also decreased in most of developing countries. It is also interesting to find that there is a clear difference among developing countries. In terms of crude death rate, Latin American countries show the lowest rate, while African countries remain still high rate. The study also shows the relationship between socioeconomic indicators and fertility/mortality in developing countries. The result supports the hypothesized relationship between education and fertility. However, the effects of urbanization and income on fertility do not show consistent result. About mortality rate, however, the study shows the significant relationship between urbanization and infant mortality rate, between income and mortality. The study finally emphasizes that we should include 'AIDS' in the study of mortality in African countries.

The Pattern and Determinants of Demographic Transition in African Countries (아프리카의 인구변천 유형과 특성)

  • Chung, Sung-Ho
    • Korea journal of population studies
    • /
    • v.31 no.1
    • /
    • pp.127-146
    • /
    • 2008
  • Over the past four decades reproductive behavior has changed slowly in much of the African countries. The average total fertility rate has fallen from six or more to near five today. Between 1960 and 2000 the largest fertility decline occurred in such Northern African countries as Algeria, Libya, and Morocco. The mortality rate has decreased in most African countries. The purpose of this study is to review the pattern of demographic transition in African countries. At first, this study focuses on the fertility transition. In Africa, the total fertility rate has decreased from 6.59 to 4.85 between 1960 and 2000. The mortality rate has also decreased in most of African countries. It is also interesting to find that there is a clear difference among African countries. In terms of infant mortality rate, Libya shows the lowest rate(17), while Mali and Somalia remain still high rate(142 and 133, respectively). This study tests a path model in which infant mortality rate acts as an intermediate variable between three socioeconomic variables and the fertility rate. The findings of this paper substantiate some of our hypotheses on the interrelationships among socioeconomic variables, infant mortality rate, and fertility rate. The result also shows the indirect effects of socioeconomic variables on fertility rate via infant mortality.

The Role of Central Bank Rate on Credit Gap in Indonesia: A Smooth Transition Regression Approach

  • SUHENDRA, Indra;ANWAR, Cep Jandi
    • The Journal of Asian Finance, Economics and Business
    • /
    • v.8 no.1
    • /
    • pp.833-840
    • /
    • 2021
  • This paper examines the effect of the interest rate set by Bank Indonesia on financial system stability as measured by the credit gap in Indonesia for quarterly data for the period 1976 Q1 to 2019 Q4. We suppose that the relationship between the Central Bank rate and the credit gap is non-linear. Hence, this study applies a smooth transition regression (STR) model to investigate the relationship between these variables. Our results are: first, by performing STR estimation we obtained a threshold level of Central Bank rate of 2.01. Second, a decrease in the Central Bank rate results in a reduction in the credit gap when the Central Bank rate is above or below the threshold level. The effect of the Central Bank rate is five times greater for the high regime than for the low regime. Third, we find evidence that the effect of the exchange rate, economic growth, inflation, and GDP per capita on the credit gap for the high regime is the opposite of the low regime. We suggest that policymakers need to keep the Central Bank interest rate low and stable so that the role of the bank as a financial intermediary remains stable and conducive to strengthening financial stability.

Development of Explosion Model of Energetic Materials Considering Shock to Detonation Transition and Damage by External Impact (외부 충격에 의한 손상을 고려한 화약과 추진제의 폭발모델 개발)

  • Kim, Bohoon;Yoh, Jai-ick
    • 한국연소학회:학술대회논문집
    • /
    • 2012.11a
    • /
    • pp.97-99
    • /
    • 2012
  • A pressure-based BOIK model considering Shock to Detonation Transition(SDT) and damage due to external fragment or bullet stimuli impact on energetic materials and analytical approach for determination of free parameters are proposed. The rate of product mass fraction(${\lambda}$) consists of ignition term that represents the initiation due to shock compression and growth term that describes propagation of detonation wave and strain term representing the morphological deformation induced by external impact.

  • PDF

A Study on the Transition Probability Matrix set from a Transfer Line Model (자동 생산라인 모형에서의 Transition Probability Matrix에 관한 연구)

  • No, Hyeong-Min
    • Journal of Korean Institute of Industrial Engineers
    • /
    • v.11 no.2
    • /
    • pp.1-9
    • /
    • 1985
  • In this study, two stage transfer line with limited repair capability is modeled to formulate optimal dynamic repair priority policy. The method of Markov Chains is used to analyze the analytical model of this line. An efficient algorithm is developed, utilizing the block tridiagonal structure of the transition probability matrix, to obtain the steady state probabilities and system performance measures, such as the steady state production rate of the line and the average in-process inventory in the interstage buffer.

  • PDF