Ultra-Low Fertility in Korea: The Role of Tempo Effect

Background: The total fertility rate (TFR) in South Korea has fallen below 1.3 since 2001. However, little is known about the role of the rapid shift towards late childbearing in driving Korean fertility decline to this “ultra-low” level. Objective: We provide an in-depth analysis of period fertility trends by birth order in South Korea from 1981 to 2014 when the period TFR fell from 2.66 to extreme low levels. Methods: We combine census and birth registration data to estimate period and cohort fertility indicators by birth order. We compare changes in conventional TFR with tempo- and parity-adjusted total fertility rate (TFRp*) and their birth order-specific components. Results: Tempo effect linked to the shift towards delayed childbearing has had a strong and persistent negative influence on period TFRs in Korea since the early 1980s. Without the shift to later childbearing, period fertility rates in Korea would consistently stay higher and would decline more gradually, falling below a threshold of very low fertility, 1.5, only in 2014. The postponement of childbearing and the resulting tempo effect were strongest in the early 2000s, when Korean TFR reached the lowest levels. More recently, Korean fertility has been characterized by diminishing tempo effect and falling first and second birth rates. This trend marks a break with the previous pattern of almost universal fertility and a strong two-child family model. Contribution: Our study demonstrates the importance of tempo effect in explaining the shift to “ultra-low” fertility in Korea and in East Asia

Old habits die hard? Lingering son preference in an era of normalizing sex ratios at birth in South Korea

South Korea was among the first countries to report both an abnormally high sex ratio at birth (SRB) and its subsequent normalization. We examine the role of son preference in driving fertility intentions during a period of declining SRB and consider the contribution of individual characteristics and broader social context to explaining changes in intentions. We employ data from the National Survey on Fertility, Family Health and Welfare that span 1991–2012. We find that reported son preference declined to a great extent but remained substantial by the end of the observation period, and that the intention to have a third child still differed by sex of existing children. Change in individual-level factors does not explain the decline in son preference, suggesting that broad social changes were also important. This study provides a better understanding of how son preference evolves in the post-transitional context of very low fertility

Management of pediatric keratoconus - evolving role of corneal collagen cross-linking: an update.

Pediatric keratoconus demonstrates several distinctive management issues in comparison with adult keratoconus with respect to under-diagnosis, poor compliance and modifications in treatment patterns. The major concerns comprise of the accelerated progression of the disease in the pediatric age group and management of co-morbidities such as vernal keratoconjuntivitis. Visual impairment in pediatric patients may affect social and educational development and overall negatively impact their quality of life. The treatment algorithm between adults and pediatric keratoconus has been similar; comprising mainly of visual rehabilitation with spectacles, contacts lenses (soft or rigid) and keratoplasty (lamellar or penetrating) depending on the stage of the disease. There is a paradigm shift in the management of keratoconus, a new treatment modality, corneal collagen crosslinking (CXL), has been utilized in adult keratoconic patients halting the progression of the disease. CXL has been utilized for over a 10 year period and based on the evidence of efficacy and safety in the adult population; this treatment has been recently utilized in management of pediatric keratoconus. This article will present an update about current management of pediatric keratoconus with special focus on CXL in this age group

Tunneling images of a 2D electron system in a quantizing magnetic field

We have applied a scanning probe method, Subsurface Charge Accumulation (SCA) imaging, to resolve the local structure of the interior of a semiconductor two-dimensional electron system (2DES) in a tunneling geometry. Near magnetic fields corresponding to integer Landau level filling, submicron scale spatial structure in the out-of-phase component of the tunneling signal becomes visible. In the images presented here, the structure repeats itself when the filling factor is changed from nu=6 to nu=7. Therefore, we believe the images reflect small modulations in the 2DES density caused by the disorder in the sample.Comment: 2 pages, 2 color figures, submitted to LT23 proceeding

Neural Correlates Related to Anxiety in Attentional Inhibition Control: an Erp Study

We investigated the effect of anxiety on attentional inhibitory control using event-related potentials (ERPs) and measuring the response time. Nineteen participants performed a multisource interference task; three-digit numbers and emotional faces were used as visual stimuli. The P100 and P300 ERP-components and response time values were used to evaluate whether ERP parameters and behavioral responses are associated with increased anxiety. Higher anxiety was associated with a longer latency and reduced amplitude of the P300 component at F3, whereas higher anxiety was associated with a shorter latency and higher amplitude of P300 at F4. The longer P300 latency at F3 was especially related to the response time to the target number with negative-expression faces as distracters.Ми досліджували вплив рівня тривожності на гальмівний контроль уваги з використанням реєстрації пов’язаних із подією потенціалів (ППП) та вимірювання часу реакції. 19 тестованих виконували мультистимульний тест з інтерференцією; як візуальні стимули застосовували зображення тризначних чисел та облич з емоціональними виразами. Параметри Р100 та Р300 компонентів ППП та час реакції брали до уваги для того, щоб визначити можливість асоційованості параметрів ППП та поведінкових відповідей з рівнем тривожності. Підвищена тривожність була асоційована з довшими латентними періодами та зниженою амплітудою компонента Р300 у відведенні F3, тоді як такий рівень тривожності асоціювався з меншими величинами латентного періоду цієї ж самої хвилі та її вищою амплітудою у відведенні F4. Більший латентний період Р300 у відведенні F3 особливо чітко корелював із часом відповіді на цільове число на тлі облич із негативними виразами як відволікаючих факторів

The point prevalence and associated factors of nasal methicillin-resistant Staphylococcus aureus colonisation in eight geriatric hospitals in Korea

ABSTRACTThe prevalence and associated factors of nasal methicillin-resistant Staphylococcus aureus (MRSA) colonisation were investigated among patients in geriatric hospitals in Korea. S. aureus was isolated from 317 (50.2%) of 632 patients. The nasal MRSA colonisation prevalence was 36.1%. In bivariate analysis, stay in an intensive care unit, decreased functional status, recent use of antibiotics, use of urinary catheters and the existence of skin breaks were associated with nasal MRSA colonisation (p < 0.05). Of these factors, only decreased functional status and recent use of systemic antibiotics were associated independently with nasal MRSA colonisation following logistic regression analysis

A Method for Assaying Deubiquitinating Enzymes

A general method for the assay of deubiquitinating enzymes was described in detail using (125)I-labeled ubiquitin-fused αNH-MHISPPEPESEEEEEHYC (referred to as Ub-PESTc) as a substrate. Since the tyrosine residue in the PESTc portion of the fusion protein was almost exclusively radioiodinated under a mild labeling condition, such as using IODO-BEADS, the enzymes could be assayed directly by simple measurement of the radioactivity released into acid soluble products. Using this assay protocol, we could purify six deubiquitinating enzymes from chick skeletal muscle and yeast and compare their specific activities. Since the extracts of E. coli showed little or no activity against the substrate, the assay protocol should be useful for identification and purification of eukaryotic deubiquitinating enzymes cloned and expressed in the cells

Effects of phosphate and hydrogen peroxide on the performance of a biological activated carbon filter for enhanced biofiltration

Biofilm formation on biofilters can influence their hydraulic performance, thereby leading to head loss and an increase in energy use and costs for water utilities. The effects of a range of factors, including hydrogen peroxide and phosphate, on the performance of biological activated carbon (BAC) and biofilm formation were investigated using laboratory-scale columns. Head loss, total carbohydrates, and proteins were reduced in the nutrient-enhanced, oxidant-enhanced, and nutrient + oxidant-enhanced BAC filters. However, there were no changes in the removal of dissolved organic matter, trihalomethane formation potential, or selected trace organic contaminants. The biofilm formation on polyvinyl chloride and stainless steel coupons using the laboratory biofilm reactor system was lower when the effluent from a nutrient-enhanced column was used, which indicated that there was less biofilm formation in the distribution systems. This may have been because the effluent from the nutrient-enhanced column was more biologically stable. Therefore, enhanced biofiltration could be used not only to reduce head loss in biofilters, but also to delay biofilm formation in distribution systems