The 100 Most-Cited Articles Focused on Ultrasound Imaging: A Bibliometric Analysis.

Purpose The number of citations that an article has received reflects its impact on a particular research area. The aim of this study was to identify the 100 most-cited articles focused on ultrasound (US) imaging and to analyze the characteristics of these articles. Methods We determined the 100 most-cited articles on US imaging via the Web of Science database, using the search term. The following parameters were used to analyze the characteristics of the 100 most-cited articles: publication year, journal, journal impact factor, number of citations and annual citations, authors, department, institution, country, type of article, and topic. Results The number of citations for the 100 most-cited articles ranged from 1849 to 341 (median: 442.0) and the number of annual citations ranged from 108.0 to 8.1 (median: 22.1). The majority of articles were published in 1990 - 1999 (39 %), published in radiology journals (20 %), originated in the United States (45 %), were clinical observation studies (67 %), and dealt with the vessels (35 %). The Department of Internal Medicine at the University of California and the Research Institute of Public Health at the University of Kuopio (n = 4 each) were the leading institutions and Salonen JT and Salonen R (n = 4 each) were the most prolific authors. Conclusion Our study presents a detailed list and analysis of the 100 most-cited US articles, which provides a unique insight into the historical development in this field.

Effects of Per-diem payment on the duration of hospitalization and medical expenses according to the palliative care demonstration project in Korea.

OBJECTIVES: The aim of this study was to examine the impacts of a government-directed palliative care demonstration (PCD) project, Per-diem Payment System (PDPS), on length of stay (LOS), hospital costs, resource usage and healthcare quality during the searched period from January in 2009 to December in 2010. STUDY DESIGN: A retrospective claim data review. METHODS: Individuals who had been eligible for the palliative care payment policy, PDPS, during 2 years (from 2009 to 2010) were assigned to the case group including seven hospitals (n = 3117). Those (seven hospitals) who were not come eligible for the palliative care payment policy were assigned to the control group (n = 2347) with fee for service. The data used in this study were electronically submitted requests of payment to the Health Insurance Review Agency during the period January 2009 to December 2010. RESULTS: After the PCD project, the length of stay for palliative patients with cancer diseases decreased by 2.56% (ß = -0.026; p-value = 0.0001) among patients hospitalized in a PCD project compared with patients hospitalized in seven hospitals that was not designed as a PCD project. Compared with costs before the PCD project, costs decreased by 0.76% (ß = 0.013; p-value = 0.0001). CONCLUSIONS: We provided evidence regarding the change in the societal burden due to palliative care. Although there was a reduction of direct medical costs reported in limited number of hospitals, in the long term, we can anticipate an expanding impact on medical costs in all palliative hospitals. Copyright © 2016 John Wiley & Sons, Ltd.

Association of lipid parameters and insulin resistance with bone health in South Korean adolescents.

UNLABELLED: This study investigated the association between lipid profiles and insulin resistance and bone mineral content (BMC) in Korean adolescents and found that BMC was inversely associated with triglyceride (TG) and homeostasis model assessment of insulin resistance (HOMA-IR). This association did not differ according to obesity status in either boys or girls. INTRODUCTION: To prevent future osteoporosis, it is important to identify factors that affect bone health in adolescents as well as adults. This study aimed to examine the association between lipid profiles and insulin resistance and BMC in Korean adolescents. METHODS: Data from 706 boys and 621 girls, who participated in the Korea National Health and Nutrition Examination Survey from 2008 to 2011, were analyzed. Lipid profiles were measured, and HOMA-IR was calculated to assess insulin resistance. BMC was measured for the total femur, femur neck, and lumbar spine by using whole-body dual-energy X-ray absorptiometry (DXA). RESULTS: TG level and HOMA-IR were negatively correlated with BMC at all three sites in boys. In girls, TG level showed a negative correlation with BMC at the femur neck and lumbar spine, and HOMA-IR was negatively associated with BMC at the femur neck only. These inverse associations did not differ according to obesity status in either sex. Adjusted means of BMC at the three sites in boys tended to decrease in the higher tertile groups of TG and HOMA-IR, and the adjusted means of BMC for the total femur in girls tended to decrease in the higher tertile groups of TG and HOMA-IR. CONCLUSIONS: BMC was inversely associated with TG and HOMA-IR in Korean adolescents, and this association was more pronounced in boys. This association did not differ according to obesity status in either sex.

Generation of axially modulated plasma waveguides using a spatial light modulator.

We demonstrate the generation of axially modulated plasma waveguides using spatially patterned high-energy laser pulses. A spatial light modulator (SLM) imposes transverse phase front modulations on a low-energy (10 mJ) laser pulse which is interferometrically combined with a high-energy (130-450 mJ) pulse, sculpting its intensity profile. This enables dynamic and programmable shaping of the laser profile limited only by the resolution of the SLM and the intensity ratio of the two pulses. The plasma density profile formed by focusing the patterned pulse with an axicon lens is likewise dynamic and programmable. Centimeter-scale, axially modulated plasmas of varying shape and periodicity are demonstrated.

The preventive effects of lifestyle intervention on the occurrence of diabetes mellitus and acute myocardial infarction in metabolic syndrome.

OBJECTIVES: Metabolic syndrome (MS), as a precursor of diabetes mellitus (DM) and cardiovascular disease, is increasing steadily worldwide. We examined the preventive effects of lifestyle intervention on the occurrence of DM and acute myocardial infarction (AMI) in MS. STUDY DESIGN: Observational study on disease occurrence after lifestyle intervention. METHODS: The lifestyle intervention was administered to subjects with MS participating in a metropolitan lifestyle intervention program for 1 year. The same numbers of non-participating age- and sex-matched subjects with MS were randomly extracted from national health examination data. After intervention or examination, new occurrences of hypertension, DM, and AMI were identified through the national health insurance claims data during 1 year. For DM and AMI, multivariate logistic regression analysis for the factors affecting each disease was performed. RESULTS: In the intervention group and the control group (14,918 in each group), the occurrence of hypertension was 555 (6.07%) and 751 (8.33%), the occurrence of DM was 324 (2.55%) and 488 (3.89%), the occurrence of dyslipidemia was 321 (2.59%) and 373 (2.72%), and the occurrence of AMI was 13 (0.09%) and 26 (0.17%), respectively. In multivariate logistic regression analysis, adjusted odds ratios for intervention were 0.752 (95% confidence interval [CI]: 0.644-0.879) and 0.499 (95% CI: 0.251-0.992) for DM and AMI, respectively, indicating that lifestyle intervention has a preventive effect. CONCLUSIONS: Lifestyle intervention in MS has preventive effects on the occurrence of DM and AMI, and long-term follow-up is needed to evaluate these preventive effects in more detail.

Cryogenically cooled 946nm Nd:YAG laser.

We present the first multi-Watt demonstration of a diode pumped cryogenically cooled neodymium-doped yttrium aluminum garnet (YAG) laser operating at 946 nm on the (4)F(3/2) → (4)I(9/2) transition. 3.8 W of continuous wave output power for 12.8 W of absorbed pump was obtained with a slope efficiency of 47%. In addition, we made an extensive characterization of the spectroscopic properties around the pump and laser wavelengths over the temperature range of 77 K to 300 K to find an increase of ~2.5 times for both the absorption and emission cross sections at the lowest temperature.

Quasi-phase-matched laser wakefield acceleration.

The energy gain in laser wakefield acceleration is ultimately limited by dephasing, occurring when accelerated electrons outrun the accelerating phase of the wakefield. We apply quasi-phase-matching, enabled by axially modulated plasma channels, to overcome this limitation. Theory and simulations are presented showing that weakly relativistic laser intensities can drive significant electron energy gains.

Synthesis and photoluminescence of novel NaLi2PO4:Tb(3+) nanophosphors for near-ultraviolet excited light emitting diodes.

A series of Tb(3+)-activated NaLi2PO4 novel nano-crystalline phosphors was synthesized by the solution combustion method. The prepared Na(1-x)Li2PO4:xTb(3+) (0.01 ≤ x ≤ 0.1) phosphors crystallized in the orthorhombic crystal structure. Its effective absorption in the near ultraviolet range allowed highly efficient green emission. The Na(1-x)Li2PO4:xTb(3+) phosphors showed characteristic (5)D4 --> (7)FJ (J = 3, 4, 5, and 6) transitions of Tb(3+), i.e., (5)D4 --> (7)F6 (488 nm), (5)D4 --> (7)F5 (545 nm), (5)D4 --> (7)F4 (583 nm), and (5)D4 --> (7)F3 (622 nm). The Na0.95Li2PO4:0.05Tb(3+) phosphor showed the most excellent emission efficiency. The present work suggests that the Na0.95Li2PO4:0.05Tb(3+) is a potential green-emitting phosphor for near ultraviolet excited light emitting diodes.

Measuring the burden of disease due to climate change and developing a forecast model in South Korea.

OBJECTIVES: Climate change influences human health in various ways, and quantitative assessments of the effect of climate change on health at national level are becoming essential for environmental health management. STUDY DESIGN: This study quantified the burden of disease attributable to climate change in Korea using disability-adjusted life years (DALY), and projected how this would change over time. METHODS: Diseases related to climate change in Korea were selected, and meteorological data for each risk factor of climate change were collected. Mortality was calculated, and a database of incidence and prevalence was established. After measuring the burden of each disease, the total burden of disease related to climate change was assessed by multiplying population-attributable fractions. Finally, an estimation model for the burden of disease was built based on Korean climate data. RESULTS: The total burden of disease related to climate change in Korea was 6.85 DALY/1000 population in 2008. Cerebrovascular diseases induced by heat waves accounted for 72.1% of the total burden of disease (hypertensive disease 1.82 DALY/1000 population, ischaemic heart disease 1.56 DALY/1000 population, cerebrovascular disease 1.56 DALY/1000 population). According to the estimation model, the total burden of disease will be 11.48 DALY/1000 population in 2100, which is twice the total burden of disease in 2008. CONCLUSIONS: This study quantified the burden of disease caused by climate change in Korea, and provides valuable information for determining the priorities of environmental health policy in East Asian countries with similar climates.

Rheological and tribological properties of native potato starch agglomerated by fluidized bed granulator.

We explored the rheological and tribological properties of potato starch agglomerated with a sugar binder (maltodextrin or lactose) at various concentrations by using a fluidized bed granulator. The magnitudes of consistency index and apparent viscosity of agglomerated potato starch (APS) decreased as the binder concentration was increased. Moreover, APS with a sugar binder showed lower viscoelastic moduli and higher tan δ values compared to APS with water as the binder (the control). The gel strength of all agglomerates decreased as the sugar concentration was increased. All samples showed anti-thixotropic behavior, and especially, APS with 20 % lactose showed a small anti-thixotropic area. Utilizing the Arrhenius equation clearly elucidated the effect of temperature on the apparent viscosity of all the samples. Although the maltodextrin concentration had little influence on the activation energy of APS, it increased as the lactose concentration was increased. APS samples with a sugar binder showed greater friction coefficient values compared to the control, with maltodextrin having a significant impact. The findings indicate that the rheological and tribological properties of APS rely on the type and concentration of sugar binder.

Shock formation in supersonic cluster jets and its effect on axially modulated laser-produced plasma waveguides.

We examine the generation of axially modulated plasmas produced from cluster jets whose supersonic flow is intersected by thin wires. Such plasmas have application to modulated plasma waveguides. By appropriately limiting shock waves from the wires, plasma axial modulation periods can be as small as 70 µm, with plasma structures as narrow as 45 µm. The effect of shocks is eliminated with increased cluster size accompanied by a reduced monomer component of the flow.

Electrical and optical properties of indium zinc oxide (IZO) thin films by continuous composition spread.

Indium zinc oxide (IZO) films were deposited on glass substrate at room temperature using off-axis RF sputtering-continuous composition spread (CCS) system. The full range composition of IZO films were controlled by the deposition rate and thickness profiles of In2O3 and ZnO target. The structural, electrical and optical properties of IZO thin films were measured as functions of position. IZO thin film had the lowest resistivity and highest carrier concentration at the position of 15 mm (5.02 x 10(-4) omega cm, 3.9 x 10(20)/cm3). And IZO thin film had high transmittance in visible region at measured all positions. This study has investigated to explore the new composition of IZO films using CCS system.

Fabrication and electrochemical properties of hemisphere structured 3D Li(Li0.2Mn0.54Co0.13Ni0.13)O2 cathode thin film for all-solid-state lithium battery.

The Li[Li0.2Mn0.54Ni0.13Co0.13]O2 cathode thin films were deposited on planar, hemisphere, linked hemisphere, and isolated hemisphere structured Pt current collector thin films to investigate the effect of 3-dimensional (3-D) structure for the electrochemical properties of active cathode thin films. The films of linked hemisphere structure shows the highest initial discharge capacity of 140 microA h/cm2-microm which is better than those of planar (62 microA h/cm2-microm), hemisphere (94.6 microA h/cm2-microm), and isolated hemisphere (135 microA h/cm2-microm) films due to increase of surface area for cathode thin films. Linked hemisphere shows the biggest capacity and the best retention rate because 6 nanobridges of each hemisphere bring strong connection.

Measuring the burden of chronic diseases in Korea in 2007.

OBJECTIVES: This study was performed to measure the burden of disease from premature death and disability for chronic diseases in Korea in 2007. STUDY DESIGN: Chronic diseases were defined using the WHO definitions. Disability-adjusted life years (DALY) were used to analyse insurance claim data. METHODS: This was a population-based study and included the total population of Korea. DALYs were used to analyse insurance claim data. Years of life lost (YLL) and years lost to disability (YLD) were measured in terms of incidence rate and number of deaths. DALYs were aggregated to YLL and YLD. To ensure code validity, only patients who had visited a tertiary hospital or a clinic three or more times for the same disease were included. RESULTS: Cerebrovascular disease was the leading contributor to the chronic disease burden, with a value of 907.4, followed by diabetes mellitus (899), ischaemic heart disease (710), cirrhosis of the liver (616.5), chronic obstructive pulmonary disease (512.9), asthma (503.1), hypertensive heart disease (407.5), stomach cancer (356) and peptic ulcer disease (292.5). As these results demonstrate, the highest ranked diseases were cardio-cerebrovascular or related diseases, as well as the fact that hypertension, diabetes mellitus and related complications, which are associated diseases, have became increasingly severe problems. And the rural areas have a higher burden of disease than metropolitan cities. According to difference in social status, Medicaid 2 group has more burden of disease than other groups. CONCLUSIONS: It has been possible to present evidence regarding the burden of diseases and the relatively high risk of cardio-cerebrovascular disease. If the various types of cancer were combined and then the calculating tool applied, the burden would likely be greater than that of cardio-cerebrovascular disease. However, based on DALY, ischaemic heart disease demonstrated a remarkable increase compared to the rate in the previous study based on 2002 data. Underprivileged people in particular have been struggling - with chronic diseases.

Mutations in the activin receptor-like kinase 1 gene in hereditary haemorrhagic telangiectasia type 2.

Hereditary haemorrhagic telangiectasia, or Osler-Rendu-Weber (ORW) syndrome, is an autosomal dominant vascular dysplasia. So far, two loci have been demonstrated for ORW. Linkage studies established an ORW locus at chromosome 9q3; endoglin was subsequently identified as the ORW1 gene. A second locus, designated ORW2, was mapped to chromosome 12. Here we report a new 4 cM interval for ORW2 that does not overlap with any previously defined. A 1.38-Mb YAC contig spans the entire interval. It includes the activin receptor like kinase 1 gene (ACVRLK1 or ALK1), a member of the serine-threonine kinase receptor family expressed in endothelium. We report three mutations in the coding sequence of the ALK1 gene in those families which show linkage of the ORW phenotype to chromosome 12. Our data suggest a critical role for ALK1 in the control of blood vessel development or repair.

A randomized phase II study of irinotecan plus cisplatin versus irinotecan plus capecitabine with or without isosorbide-5-mononitrate in advanced non-small-cell lung cancer.

BACKGROUND: We investigated the efficacy of irinotecan/cisplatin (IP) versus irinotecan/capecitabine (IX) with or without isosorbide-5-mononitrate (ISMN) in chemo-naïve advanced non-small-cell lung cancer. PATIENTS AND METHODS: Initially, 74 patients were randomly assigned to either IP or IX. Given the potential benefits of ISMN on chemotherapy, the protocol was amended during the study. Subsequently, 72 patients were randomly assigned to either IP + ISMN or IX + ISMN. Patients were treated with predefined second-line therapies (docetaxel/capecitabine for IP or IP + ISMN, docetaxel/cisplatin for IX or IX + ISMN) when disease progressed. RESULTS: A total of 146 received treatment. Response rate (RR), median progression-free survival (PFS) and overall survival (OS) were 49%, 5.5 months, 14.5 months in IP; 33%, 3.3 months, 13.0 months in IP + ISMN; 30%, 4.3 months, 16.1 months in IX; and 25%, 3.4 months, 13.6 months in IX + ISMN, respectively. While IP arm showed a trend toward higher RR and longer PFS than IX arm, IX arm showed a trend toward longer OS than IP arm. No significant differences were observed between IP + ISMN and IX + ISMN. CONCLUSION: IP showed better RR and PFS but no OS benefit when compared with IX. The addition of ISMN to IP or IX chemotherapy did not seem to improve the treatment outcome.

The influence of hospital volume and surgical treatment delay on long-term survival after cancer surgery.

BACKGROUND: We conducted a population-based retrospective cohort study to investigate the influence of hospital volume, delay of surgery, and both together on the long-term survival of postoperative cancer patients. METHODS: Using information from the Korea Central Cancer Registry from 2001 through 2005 and the National Health Insurance claim database, we determined survival for 147 682 patients who underwent definitive surgery for any of six cancers. RESULTS: Regardless of cancer site, surgical patients in low- to medium-volume hospitals showed significantly worse survival [adjusted hazard ratio (aHR) = 1.36-1.86] than those in high-volume hospitals in multivariable analyses. Among the latter, treatment delays > 1 month were not associated with worse survival for stomach, colon, pancreatic, or lung cancer but were for rectal [aHR = 1.28; 95% confidence interval (CI), 1.17-1.40] and breast (aHR = 1.59; 95% CI, 1.37-1.84) cancer. For patients in low- to medium-volume hospitals, treatment delay was associated with worse survival for all types of cancer (aHR = 1.78-3.81). CONCLUSION: Our findings suggest that the effect of hospital volume and surgical treatment delay on overall survival of cancer patients should be considered in formulating or revising national health policy.

Effect of vardenafil on nitric oxide synthase expression in the paraventricular nucleus of rats without sexual stimulation.

Vardenafil hydrochloride (HCl) is a potent and selective phosphodiesterase type-5 (PDE-5) inhibitor that enhances nitric oxide (NO)-mediated relaxation of human corpus cavernosum and NO-induced rabbit penile erection, and enhances erectile function in patients. In the present study, the effect of vardenafil on nitric oxide synthase (NOS) and neuronal NOS expressions in the paraventricular nucleus (PVN) of rats without sexual stimulation was investigated using nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) histochemistry and neuronal NOS (nNOS) immunohistochemistry and western blot analysis. The present results showed that NOS and nNOS expression in the PVN was increased by vardenafil treatment as the dose- and duration-dependently without sexual stimulation. The phosphodiesterase type-5 inhibitor, vardenafil, augmented NOS expression in the brain without sexual stimulation. The present study suggests that sexual behaviour can be directly modulated by neurotransmitters such as nitric oxide.

Efficacy and tolerability of mirtazapine in treating major depressive disorder with anxiety symptoms: an 8-week open-label randomised paroxetine-controlled trial.

AIMS: Prominent anxiety symptoms are related to poor clinical course and outcome in major depressive disorder (MDD). The aim of this randomised, open-label, controlled study is to compare the efficacy and tolerability of mirtazapine in the form of orally disintegrating tablets against paroxetine in treating MDD patients with anxiety symptoms. METHODS: A total of 60 MDD patients with a score above 18 on the Hamilton Anxiety Rating Scale (HARS) were randomly assigned to 8 weeks of fixed dosing treatment with mirtazapine (15-30 mg/day) and paroxetine (10-20 mg/day). Efficacy was primarily assessed with the HARS and with the 17-item Hamilton Depression Rating Scale (HDRS) at weeks 1, 2, 4 and 8 after treatment. Tolerability was assessed from adverse events. RESULTS: The generalised estimating equations (GEE) models showed that the rates of improvement in HDRS scores from baseline to week 8 were similar between mirtazapine and paroxetine groups. However, patients with mirtazapine exhibited earlier improvement in HARS scores at weeks 1 and 2. Week-by-week GEE models showed that these significant differences in improvement of HARS scores between the two treatment groups were detectable from the first evaluation after the treatment (week 1) and maintained through week 2. There was no difference in the overall frequency of adverse events experienced between the two treatment groups. The most common adverse event in the mirtazapine group was somnolence (n = 8), whereas that in the paroxetine group was gastrointestinal discomfort (n = 9). CONCLUSIONS: Mirtazapine and paroxetine were equally effective and well tolerated for the depressive symptoms in MDD patients with the high level of anxiety symptoms. Mirtazapine was, however, more effective in reducing the anxiety symptoms than paroxetine in the early weeks of treatment, suggesting that mirtazapine may have an earlier-onset action for the anxiety symptoms in MDD patients.

Population genetic structure of wild and hatchery black rockfish Sebastes inermis in Korea, assessed using cross-species microsatellite markers.

The population structure of the black rockfish, Sebastes inermis (Sebastidae), was estimated using 10 microsatellite loci developed for S. schlegeli on samples of 174 individuals collected from three wild and three hatchery populations in Korea. Reduced genetic variation was detected in hatchery strains [overall number of alleles (N(A)) = 8.07; allelic richness (A(R)) = 7.37; observed heterozygosity (H(O)) = 0.641] compared with the wild samples (overall N(A) = 8.43; A(R) = 7.83; H(O) = 0.670), but the difference was not significant. Genetic differentiation among the populations was significant (overall F(ST) = 0.0237, P < 0.05). Pairwise F(ST) tests, neighbor-joining tree, and principal component analyses showed significant genetic heterogeneity among the hatchery strains and between wild and hatchery strains, but not among the wild populations, indicating high levels of gene flow along the southern coast of Korea, even though the black rockfish is a benthic, non-migratory marine species. Genetic differentiation among the hatchery strains could reflect genetic drift due to intensive breeding practices. Thus, in the interests of optimal resource management, genetic variation should be monitored and inbreeding controlled within stocks in commercial breeding programs. Information on genetic population structure based on cross-species microsatellite markers can aid in the proper management of S. inermis populations.