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Abstract The high genetic diversity of rear‐edge refugia populations is predicted to have resulted from species repeatedly migrating to low latitudes during glacial periods over the course of Quaternary climate change. However, several recent empirical studies of cold‐tolerant plants revealed the opposite pattern. We investigated whether current habitats of the cold‐adapted and range‐restricted Bupleurum euphorbioides in the Baekdudaegan, South Korea, and North Korea could be interglacial refugia, and documented how their rear‐edge populations differ genetically from those of typical temperate species. Phylogeographic analysis and ecological niche modeling (ENM) were used. The genetic structure was analyzed using microsatellite markers and chloroplast DNA sequences. The congener B. longiradiatum was included as a typical temperate plant species. Despite having almost identical life history traits, these congeneric species exhibited contrasting patterns of genetic diversity. ENM revealed an apparent maximum range contraction during the last interglacial. In contrast, its range expanded northward to the Russian Far East (Primorsky) during the Last Glacial Maximum. Thus, we hypothesize that B. euphorbioides retreated to its current refugia during interglacial periods. Unlike populations in the central region, the rear‐edge populations were genetically impoverished and uniform, both within populations and in pooled regional populations. The rear‐edge B. euphorbioides survived at least one past interglacial, contributing to the species’ genetic diversity. We believe that such genetic variation in the cold‐adapted B. euphorbioides gives the species the necessary adaptations to survive an upcoming favorable environment (the next glacial), unless there is artificial environmental change.

The KSR-3 magnetometers consist of the fluxgate magnetometer (MAG/AIM) for acquiring the rocket flight attitude information, and the search-coil magnetometer (MAG/SIM) for the observation of the Earth's magnetic fluctuations. The position (latitude, longitude, and height) and flight condition (the transformation angle) of the rocket is measured after the data based on these two magnetometers are compared with IGRF. The gap in the vector of magnetic field between the position of the launching point and an impact point is taken into account in data reduction. Angular variation of pitch, yaw, and roll can be researched when the data is applied to the coordinate system of the rocket.

This paper describes the re-design and the calibration results of the MAG digital circuit onboard the KSR-3. We enhanced the sampling rate of magnetometer data. Also, we reduced noise and increased authoritativeness of data. We could confirm that AIM resolution was decreased less than 1nT of analog calibration by a digital calibration of magnetometer. Therefore, we used numerical-program to correct this problem. As a result, we could calculate correction and error of data. These corrections will be applied to magnetometer data after the launch of KSR-3.

The solar wind contributes to the formation of unique space environment called the Earth's magnetosphere by various interactions with the Earth's magnetic field. Thus the solar-terrestrial environment affects the Earth's magnetic field, which can be observed with an instrument for the magnetic field measurement, the magnetometer usually mounted on the rocket and the satellite and based on the ground observatory. The magnetometer is a useful instrument for the spacecraft attitude control as well as the Earth's magnetic field measurements for a scientific purpose. In this paper, we present the preliminary design and test results of the two onboard magnetometers of KARI's (Korea Aerospace Research Institute) sounding rocket, KSR-3, which will be launched four times during the period of 2001-02. The KSR-3 magnetometers consist of the fluxgate magnetometer, MAG/AIM (Attitude Information Magnetometer) for acquiring the rocket flight attitude information, and of the search-coil magnetometer, MAG/SIM (Scientific Investigation Magnetometer) for the observation of the Earth's magnetic field fluctuations. With the MAG/AIM, the 3-axis attitude information can be acquired by the comparison of the resulting dc magnetic vector field with the IGRF (International Geomagnetic Reference Field). The Earth's magnetic field fluctuations ranging from 10 to 1,000 Hz can also be observed with the MAG/SIM measurement.

KARI (Korea Aerospace Research Institute) has measured the ozone density profiles over the Korean Peninsular since the launch of the Korean Sounding Rocket-I (KSR-I) in 1993. The purpose of ozone measurements is to obtain the stratospheric and mesospheric vertical ozone density profiles over the Korean Peninsular with solar UV radiometers. With the visible channel of the radiometer, the attitude variation of the rocket was corrected and compensated. Developed system is based on ozone detector designs onboard the KSR-I and KSR-II. We discuss the development of ozone detector which will be onboard the KSR-III and its circuit and vibration test results for EM Model.

The tetragonality (c/a) of a PbZr0.2Ti0.8O3 (PZT) thin film on La0.7Sr0.3MnO3/0.72Pb(Mg1/3Nb2/3)O3-0.28PbTiO3 (PMN-PT) substrates was controlled by applying an electric field on the PMN-PT substrate. The piezoelectric response of the PZT thin film under various biaxial strains was observed using time-resolved micro X-ray diffraction. The longitudinal piezoelectric coefficient (d33) was reduced from 29.5 to 14.9 pm/V when the c/a ratio of the PZT film slightly changed from 1.051 to 1.056. Our results demonstrate that the tetragonality of the PZT thin film plays a critical role in determining d33, and in situ strain engineering using electromechanical substrate is useful in excluding the extrinsic effect resulting from the variation in the film thickness or the interface between substrate. [ABSTRACT FROM AUTHOR]

Purpose: Bone is the most frequent site of metastasis among breast cancer patients. We investigated prognostic factors affecting survival following bone-only metastasis in breast cancer patients. Materials and Methods: The medical records of breast cancer patients who were treated and followed at Gangnam Severance Hospital retrospectively reviewed to identify patients with bone-only metastasis. Results: The median time from the diagnosis of bone-only metastasis to the last follow-up or death was 55.2 [95% confidence interval (CI), 38.6-71.9] months. The Kaplan-Meier overall survival estimate at 10 years for all patients was 34.9%. In the multivariate Cox regression model, bisphosphonate treatment [hazard ratio=0.18; 95% CI, 0.07-0.43], estrogen receptor positivity (hazard ratio=0.51; 95% CI, 0.28-0.94), and solitary bone metastasis (hazard ratio=0.32; 95% CI, 0.14-0.72) were significantly associated with longer overall survival in the bone-only recurrence group. Among the treatment modalities, only bisphosphonate treatment was identified as a significant prognostic factor. Conclusion: Identifying the factors influencing breast cancer mortality after bone-only metastasis will help clarify the clinical course and improve the treatment outcome for patients with breast cancer and bone-only metastasis. Bisphosphonates, as a significant prognostic factor, warrant further investigation. [ABSTRACT FROM AUTHOR]

Purpose: Some recent trials suggest that postoperative adjuvant radiotherapy (RT) may be safely omitted after breast-conserving surgery (BCS) for some patients with ductal carcinoma in situ (DCIS). In this study, we reviewed clinical outcomes of patients with DCIS treated with partial mastectomy (PM) without adjuvant RT. Materials and Methods: Medical records of 28 patients (29 breasts) with DCIS who were treated with PM, but without RT, between April 1991 and December 2010 were retrospectively analyzed. Based on established criteria (2.0 cm or less in size and no comedonecrosis), 18 patients were treated without RT after PM. Seven patients (8 breasts) who did not receive RT due to refusal were also included in this study. Three other patients were excluded because data concerning comedonecrosis were not available. Results: For the 25 patients included in this study, the mean age of the 18 patients who met the criteria was 47.9±6.2 years, and 47.6±12.7 years for the 7 patients who did not. The mean sizes of the primary tumors were 0.6±0.4 cm and 0.9±0.3 cm, respectively, in these two groups. Among these 25 patients (26 breasts) treated without RT, we observed no ipsilateral breast tumor recurrence or mortality within a mean follow-up of 84 months. Conclusion: Based on this small number of cases, patients with DCIS, who were selected for tumor size less than 2 cm and absence of comedonecrosis, may be treated successfully with BCS; adjuvant RT may be omitted. [ABSTRACT FROM AUTHOR]

To examine the morphological changes of the medial meniscus in advanced knee osteoarthritis (OA) we examined 167 knee joints of 106 patients who subsequently underwent total knee joint arthroplasty from January to May, 2007. All 106 patients were females and their ages ranged from 57 to 83 years (mean 68.7 ± 5.6 years). For patients with complete loss of medial joint space by weight-bearing radiography, the meniscal position was assessed by measuring meniscal subluxation and meniscal height. Meniscal morphology was assessed using a modified WORMS MRI-based method. Description of the prevalence of different meniscal morphologies and their respective positions are presented. The predominant type (32.2, 64.1 and 83.8% in anterior horn, mid-body and posterior horn, respectively) of meniscal morphology abnormality was a hypertrophied displaced tear. Medial meniscus height was found to be higher than lateral meniscus height. In persons with an hypertrophied meniscus the height of the medial meniscus was 8.06 ± 1.15, 10.03 ± 1.79, and 8.61 ± 1.57 mm at anterior horn, mid-body and posterior horn, respectively, compared to those in other categories whose height was 6.04 ± 0.92, 5.08 ± 1.68 and 6.43 ± 1.26 mm. A large proportion of persons with end stage varus knee OA have a paradoxically hypertrophied medial meniscus. This new finding of hypertrophied menisci highlights that not all menisci in persons with end stage OA are macerated or destroyed. [ABSTRACT FROM AUTHOR]

High tibial osteotomy (HTO) is an accepted surgical technique for the treatment of medial compartmental arthrosis of the knee in younger patients. Compared to total knee arthroplasty, HTO may be a good choice in patients who wish to continue with heavy labor and/or impact sports. Based on the rehabilitation protocol after HTO, impact sports, such as running, jumping rope, and full sports activities, are generally permitted 6 months postoperatively. Jumping rope is an excellent form of aerobic exercise, and when done properly, jumping rope can lead to a dramatic improvement in rehabilitation and full sports activities. However, an adequate evaluation should be performed prior to initiating impact sports. We present the case of a ruptured anterior cruciate ligament that occurred in a patient with an unintended increase in the tibial slope after an opening wedge HTO who was jumping rope. [ABSTRACT FROM AUTHOR]

Electric-field-driven phase transformation phenomena in multiferroic BiFeO3 are directly linked to the functionalities of electronic devices based on multiferroic materials. Understanding how the transformation evolves at the nanoscale under the influence of an electric field will provide fascinating insights into key parameters that utilize the transformation features. Here, we report both the electric-field-driven transient and permanent phase transformations in highly strained BiFeO3 thin films and their transformation dynamics at the nanoscale. We found that two distinct transient and permanent phase transformations were triggered below and above a coercive voltage of the polymorphic phase, indicating that ferroelectric polarization switching could promote permanent phase transformations. We also found that the transient transformations evolve via complex phase boundary motions between the coexisting phases, whereas permanent transformations occurred via nucleation of the other phases.

BACKGROUND: Probability of recurrence in patients with estrogen receptor (ER)-positive breast cancer remains constant for long periods. We compared tumor burden impact on late versus early recurrence in our cohort with long-term follow-up. METHODS: Five hundred and ninety five patients diagnosed with ER-positive breast cancer between 1989 and 2001 were classified into three groups: early recurrence within 5 years, late recurrence after 5 years, and no recurrence. We identified prognostic factors among the groups using logistic regression analysis. RESULTS: At median follow-up of 11.7 years, among 595 ER-positive women, 98 (16.4%) had early recurrence and 58 (9.7%) had late recurrence. On multivariate analysis, higher nodal stage (N0 vs. N2, odds ratio [OR] 3.189; N0 vs. N3, OR 9.948), higher histologic grade (grade 1 vs. grade 2, OR 3.896; grade 1 vs. grade 3, OR 5.945), age >35 years (OR 0.295), and receiving endocrine therapy (OR 0.293) affected early recurrence. Compared to no recurrence, receiving endocrine therapy (OR 0.285) was solely related to decreased risk of late recurrence. Increased risk of early recurrence was noted with the higher nodal stage when early and no recurrences were compared. This phenomenon was not found in late recurrence. In the last comparison between the early and late recurrence, higher nodal stage (N0 vs. N3, OR 16.779) and higher histologic grade (grade 1 vs. grade 3, OR 18.111) repeatedly weighted for early recurrence. CONCLUSIONS: Nodal burden had an attenuated influence on late recurrence, which suggests that, unlike early recurrence, tumor biology might have a more important role than tumor load for late recurrence in ER-positive disease.

Epitaxial oxide ferroelectric films exhibit emerging phenomena arising from complex domain configurations even at pseudoequilibrium, including the creation of domain states unfavored in nature and abrupt piezoelectric coefficients around morphotropic phase boundaries. The nanometer-sized domain configurations and their domain switching dynamics under external stimuli are directly linked to the ultrafast manipulation of ferroelectric thin films; however, complex domain switching dynamics under homogeneous electric fields has not been fully explored, especially at the nanosecond timescale. This Letter reports the nanosecond dynamics of ferroelastic-domain switching from the 90° to 180° direction using time-resolved x-ray microdiffraction under homogeneous electric fields onto an epitaxial Pb(Zr0.35, Ti0.65)O3 film capacitor. It is found that the application of electric fields induces spatially heterogeneous domain switching processes via intermediate domain structures with rotated polarization vectors. In addition, the domain switching time is shown to be inversely proportional to the magnitude of the applied electric field, and electric fields higher than 480 kV/cm are found to complete the ferroelastic switching within nanoseconds. [ABSTRACT FROM AUTHOR]