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To evaluate the impact of a vancomycin-resistant Enterococcus (VRE) screening policy change on the incidence of healthcare-associated (HA)-VRE bacteremia in an endemic hospital setting.
A quasi-experimental before-and-after study.
A 1,989-bed tertiary-care referral center in Seoul, Republic of Korea.
Since May 2010, our hospital has diminished VRE screening for admitted patients transferred from other healthcare facilities. We assessed the impact of this policy change on the incidence of HA-VRE bacteremia using segmented autoregression analysis of interrupted time series from January 2006 to December 2014 at the hospital and unit levels. In addition, we compared the molecular characteristics of VRE blood isolates collected before and after the screening policy change using multilocus sequence typing and pulsed-field gel electrophoresis.
After the VRE screening policy change, the incidence of hospital-wide HA-VRE bacteremia increased, although no significant changes of level or slope were observed. In addition, a significant slope change in the incidence of HA-VRE bacteremia (change in slope, 0.007; 95% CI, 0.001–0.013; P = .02) was observed in the hemato-oncology department. Molecular analysis revealed that various VRE sequence types appeared after the policy change and that clonally related strains became more predominant (increasing from 26.1% to 59.3%).
The incidence of HA-VRE bacteremia increased significantly after VRE screening policy change, and this increase was mainly driven by high-risk patient populations. When planning VRE control programs in hospitals, different approaches that consider risk for severe VRE infection in patients may be required.
There is limited evidence on the interaction by alcohol dehydrogenase 2 (ADH1B) (rs1229984) and aldehyde dehydrogenase 2 (ALDH2) (rs671) regarding the associations of alcohol and a methyl diet (low folate and high alcohol intake) with cancer risk, partly because of rare polymorphisms in Western populations.
In a case–control study, we estimated the ORs and 95 % CIs to evaluate the associations of ADH1B and ALDH2 genotypes with colorectal cancer (CRC) and the joint association between methyl diets and ADH1B and ALDH2 polymorphisms with CRC risk using logistic regression models.
A hospital-based case–control study.
In total, 1001 CRC cases and 899 cancer-free controls admitted to two university hospitals.
We found that alcohol intake increased the risk of CRC; OR (95 % CI) was 2·02 (1·41, 2·87) for ≥60 g/d drinkers compared with non-drinkers (Ptrend < 0·001). The associations for two polymorphisms with CRC were not statistically significant. However, we found a potential interaction of ALDH2 with methyl diets and CRC. We observed a 9·08-fold (95 % CI 1·93, 42·60) higher risk of CRC for low-methyl diets compared with high-methyl diets among individuals with an A allele of ALDH2, but the association was not apparent among those with ALDH2 GG (Pinteraction = 0·02).
Our data support the evidence that gene–methyl diet interactions may be involved in CRC risk in East Asian populations, showing that a low-methyl diet increased the risk of CRC among individuals with an A allele of ALDH2.
This research investigated patients who underwent surgery for a dilated aorta associated with a connective tissue disease or inflammatory vasculitis in children and adolescents.
Materials and Methods:
The medical records of 11 patients who underwent aortic surgery for dilatation resulting from a connective tissue disease or inflammatory vasculitis between 2000 and 2017 were retrospectively reviewed.
The median age and body weight of the patients were 9.6 years (range 5.4 months–15.5 years) and 25.8 kg (range 6.8–81.5), respectively. The associated diseases were Marfan syndrome (n = 3), Loeys-Dietz syndrome (n = 3), Kawasaki disease (n = 1), Takayasu arteritis (n = 1), PHACE syndrome (n = 1), tuberous sclerosis (n = 1), and unknown (n = 1). The most common initially affected area was the ascending aorta. During the 66.4 ± 35.9 months of follow-up, two Marfan syndrome patients died, and four patients (one Marfan syndrome and three Loeys-Dietz syndrome) had repeated aortic operation. Except for one patient, the functional class was well maintained in all patients who were followed up.
Cases of surgical treatment for a dilated aorta associated with a connective tissue disease and inflammatory vasculitis are rare in children and adolescents at our institution. Most of the patients in this study showed a tolerable postoperative course. However, the aorta showed progressive dilation over time even after surgical treatment, especially in patients with Loeys-Dietz syndrome. In these patients, close and more frequent regular follow-up is required.
This article examines the effects of electoral systems on issue ownership. This study argues that electoral rules significantly affect issue ownership because they prompt candidates to adopt different types of electoral campaigns. Compared to the single non-transferable vote (SNTV) system, the mixed-member majoritarian (MMM) system prods candidates to change the pattern of electoral campaigns from candidate-centred to issue-centred competition. In particular, partisan issue effects are more effective in gaining votes under the MMM. To support the argument, I find evidence from content analyses of party manifestos and multinomial logistic regression models of electoral surveys between the pre-reform and post-reform elections in Japan.
We trace Sn nanoparticles (NPs) produced from SnO2 nanotubes (NTs) during lithiation initialized by high energy e-beam irradiation. The growth dynamics of Sn NPs is visualized in liquid electrolytes by graphene liquid cell transmission electron microscopy. The observation reveals that Sn NPs grow on the surface of SnO2 NTs via coalescence and the final shape of agglomerated NPs is governed by surface energy of the Sn NPs and the interfacial energy between Sn NPs and SnO2 NTs. Our result will likely benefit more rational material design of the ideal interface for facile ion insertion.
To evaluate the appropriateness of the screening strategy for healthcare personnel (HCP) during a hospital-associated Middle East Respiratory Syndrome (MERS) outbreak, we performed a serologic investigation in 189 rRT-PCR–negative HCP exposed and assigned to MERS patients. Although 20%–25% of HCP experienced MERS-like symptoms, none of them showed seroconversion by plaque reduction neutralization test (PRNT).
Personality may predispose family caregivers to experience caregiving differently in similar situations and influence the outcomes of caregiving. A limited body of research has examined the role of some personality traits for health-related quality of life (HRQoL) among family caregivers of persons with dementia (PWD) in relation to burden and depression.
Data from a large clinic-based national study in South Korea, the Caregivers of Alzheimer's Disease Research (CARE), were analyzed (N = 476). Path analysis was performed to explore the association between family caregivers’ personality traits and HRQoL. With depression and burden as mediating factors, direct and indirect associations between five personality traits and HRQoL of family caregivers were examined.
Results demonstrated the mediating role of caregiver burden and depression in linking two personality traits (neuroticism and extraversion) and HRQoL. Neuroticism and extraversion directly and indirectly influenced the mental HRQoL of caregivers. Neuroticism and extraversion only indirectly influenced their physical HRQoL. Neuroticism increased the caregiver's depression, whereas extraversion decreased it. Neuroticism only was mediated by burden to influence depression and mental and physical HRQoL.
Personality traits can influence caregiving outcomes and be viewed as an individual resource of the caregiver. A family caregiver's personality characteristics need to be assessed for tailoring support programs to get the optimal benefits from caregiver interventions.
In this paper, the electrical properties of bottom-gate (BG) polycrystalline silicon (poly-Si) thin-film transistors (TFTs) by NiSi2 seed-induced lateral crystallization (SILC) and its applications are presented. Sequential lateral solidification (SLS), which is one of crystallization methods, is known to have poor electrical properties of TFTs with BG structures due to problems induced by laser. Therefore, the laser method cannot be used to well-developed production line of amorphous-Si (a-Si) TFT, resulting in large initial investment cost to change fabrication procedures. On the other hand, the BG poly-Si TFT by SILC (SILC-BGPS TFT) has basically compatible process flows with that of the a-Si TFT. The SILC-BGPS TFT exhibited threshold voltage of -3.9 V, steep subthreshold slope of 130 mV/dec, a high field-effect mobility of 129 cm2/Vs , and Ion/Ioff ratio of ∼106.
In this paper, we propose and examine a force-resisting balance control strategy for a walking biped robot under the application of a sudden unknown, continuous force. We assume that the external force is acting on the pelvis of a walking biped robot and that the external force in the z-direction is negligible compared to the external forces in the x- and y-directions. The main control strategy involves moving the zero moment point (ZMP) of the walking robot to the center of the robot's sole resisting the externally applied force. This strategy is divided into three steps. The first step is to detect an abnormal situation in which an unknown continuous force is applied by examining the position of the ZMP. The second step is to move the ZMP of the robot to the center of the sole resisting the external force. The third step is to have the biped robot convert from single support phase (SSP) to double support phase (DSP) for an increased force-resisting capability. Computer simulations and experiments of the proposed methods are performed to benchmark the suggested control strategy.
Nitrogen fixation in legumes is an important agricultural trait that results from symbiosis between the root and rhizobia. To understand the molecular basis of nodulation, recent research has been focused on the identification of nodulation-related genes by functional analysis using two major model legumes, Medicago truncatula and Lotus japonicus. Thus far, three important processes have been discovered, namely Nod factor (NF) perception, NF signalling and autoregulation of nodulation. Nevertheless, application of the results of these studies is limited for non-model legume crops because a reference genome is unavailable. However, because the cost of whole-transcriptome analysis has dropped dramatically due to the Next generation sequencer (NGS) technology, minor crops for which reference sequences are yet to be constructed can still be studied at the genome level. In this study, we sequenced the leaf and root transcriptomes of Vigna angularis (accession IT213134) and de novo assembled. Our results demonstrate the feasibility of using the transcriptome assembly to effectively identify tissue-specific peptide clusters related to tissue-specific functions and species-specific nodulation-related genes.
Direct heteroarylation polymerization was employed to synthesize a novel low bandgap polymer, used as a p-type material of polymer photovoltaic cells. To achieve low bandgap of conjugated polymers, electron donor-acceptor (D-A) alternating strategy was used. The electron-donating 3-alkylthiophene and electron-withdrawing cyanothiophene were coupled to be polymerized via direct heteroarylation polymerization. The cyano moiety of the polymer backbone allowed a strong intermolecular interaction between neighboring chains and improved the structural perfection of the crystal structure on the substrate. The solar cell devices of ITO/PEDOT:PSS/P3HT:PCBM/LiF/Al were fabricated on ITO-coated glass substrate.
Geochemical characteristics of marine sediment from the southern Drake Passage were analyzed to reconstruct variations in sediment provenance and transport paths during the late Quaternary. The 5.95 m gravity core used in this study records paleoenvironmental changes during the last approximately 600 ka. Down-core variations in trace element, rare earth element, and Nd and Sr isotopic compositions reveal that sediment provenance varied according to glacial cycles. During glacial periods, detrital sediments in the southern Drake Passage were mostly derived from the nearby South Shetland Islands and shelf sediments. In contrast, interglacial sediments are composed of mixed sediments, derived from both West Antarctica and East Antarctica. The East Antarctic provenance of the interglacial sediments was inferred to be the Weddell Sea region. Sediment input from the Weddell Sea was reduced during glacial periods by extensive ice sheets and weakened current from the Weddell Sea. Sediment supply from the Weddell Sea increased during interglacial periods, especially those with higher warmth such as MIS 5, 9, and 11. This suggests that the influence of deep water from the Weddell Sea increases during interglacial periods and decreases during glacial periods, with the degree of influence increasing as interglacial intensity increases.
Recent extensive nanomechanical experiments have revealed that the instantaneous strength and plasticity of a material can be significantly affected by the size (of sample, microstructure, or stressed zone). One more important property to be added into the list of size-dependent properties is time-dependent plastic deformation referred to as creep; it has been reported that the creep becomes more active at the small scale. Analyzing the creep in the small scale can be valuable not only for solving scientific curiosity but also for obtaining practical engineering information about the lifetime or durability of advanced small-scale structures. For the purpose, nanoindentation creep experiments have been widely performed by far. Here we critically review the existing nanoindentation creep methods and the related issues and finally suggest possible novel ways to better estimate the small-scale creep properties.
The diatoms are an ecologically important group of algae that have been extensively studied by ecologists and taxonomists. However, the large-scale patterns of diatom distribution and the factors underlying this distribution are largely unknown. The aims of this study were to identify the large-scale spatial patterns of benthic diatom assemblages in Korean streams and rivers, and to assess the importance of numerous environmental factors on diatom distribution. We classified 720 study sites based on diatom flora. Benthic diatoms, water chemistry, altitude, and riparian land cover and use were characterized by multivariate analyses, Monte Carlo permutation tests, and indicator species analysis. In total, we identified 531 diatom taxa. Diatom assemblages were mostly dominated by species of the genera Achnanthes, Navicula, Nitzschia, Cocconeis, Fragilaria (Synedra included), Cymbella, Gomphonema, and Melosira. Cluster analysis partitioned all 720 sites into eight groups based on diatom species composition. Canonical correspondence analysis indicated that altitude, land cover and use, current velocity, electrical conductivity, and nutrient levels explained a significant amount of the variation in the composition of assemblages of benthic diatoms. At the national scale, a downstream ecological gradient was apparent, from fast-flowing, mostly oligotrophic highland streams to slow-flowing, mostly eutrophic lowland rivers. Our data suggest that spatial factors explain some of the variation in diatom distribution. The present investigation of the spatial patterns of benthic diatoms, the ecological determinants of diatom occurrence, and the identification of diatom indicator species contributes to development of a program for assessing the biological integrity of lotic ecosystems in Korea.
Oxidation-induced stress evolutions in Ta thin films were investigated using ex situ microstructure analyses and in situ wafer curvature measurements. It was revealed that Ta thin films are oxidized to a crystalline TaO2 layer, which is subsequently oxidized to an amorphous tantalum pentoxide (a-Ta2O5) layer. Initial layered oxidation from Ta to TaO2 phases abruptly induces high compressive stress up to about 3.5 GPa with fast diffusion of oxygen through the Ta layer. Subsequently, it is followed by stress relaxation with the oxidation time, which is related to the slow oxidation from TaO2 to Ta2O5 phases. The initial compressive stress originates from the molar volume expansion during the layered formation of TaO2 from the Ta layer, while the relaxation of the compressive stresses is ascribed to the amorphous character of the a-Ta2O5 layer. According to Kissinger's analysis of the stress evolution during an isochronic heating process, the oxygen diffusion process through the a-Ta2O5 layer is the rate-controlling stage in the layered oxidation process of forming a a-Ta2O5/TaO2/Ta multilayer and has an activation energy of about 190.8 kJ/mol.
Although electrical pacing is of great utility in many cardiovascular diseases, its effects on the combined cardiac cell therapy have not been established. We hypothesised that mesenchymal stem cell transplantation changes cardiac sympathetic nerve and gap junction, and concomitant pacing has additional biological effects.
We monitored cardiac rhythm for 4 weeks after human mesenchymal stem cell transplantation (1 × 107, epicardial injection) in 18 dogs in vivo, seven human mesenchymal stem cell with pacing, six human mesenchymal stem cell, and five sham, and evaluated the sympathetic innervation, nerve growth factor-β; tyrosine hydroxylase, angiogenesis, von Willebrand factor, and connexin43 expressions by real time (RT)–polymerase chain reaction and immunostaining. We also measured mRNA expressions of nerve growth factor-β, von Willebrand factor, and connexin43 in vitro culture of human mesenchymal stem cell with or without pacing.
Human mesenchymal stem cell transplanted hearts expressed higher mRNA of nerve growth factor-β (p < 0.01) with sympathetic nerves (p < 0.05), higher mRNA of von Willebrand factor (p < 0.001) with angiogenesis (p < 0.001), but lower mRNA of connexin43 (p < 0.0001) with reduced gap junctions (p < 0.001) than sham. Pacing with human mesenchymal stem cell transplantation resulted in higher expression of mRNA of connexin43 (p < 0.02) and gap junctions (p < 0.001) compared with sham. In contrast, in vitro paced mesenchymal stem cell reduced expression of connexin43 mRNA (p < 0.02).
Human mesenchymal stem cell transplantation increased cardiac sympathetic innervation and angiogenesis, but reduced gap junction after transplanted in the canine heart. In contrast, concomitant electrical pacing increased gap junction expression by paracrine action.
Large-area vertically aligned silicon nanowire (Si NW) arrays were synthesized with a controlled length (0.3 ˜ 9 μm) by the chemical etching of n-type silicon substrates. Upon their excitation using a fs Ti-sapphire laser pulse (800 nm), their THz emission intensity exhibits strong dependence on their length; the intensity increases sharply up to a length of 3 μm and then decreases slightly, due to the complete absorption of the optical pump power. The Raman scattering spectrum exhibits the same behavior as that of the THz emission. We suggest that the field enhancement by localized surface plasmons induces more efficient THz emission or Raman scattering for the longer Si NWs. The photocurrent measured in a photoelectrochemical cell showed consistently the length dependence with a maximum value at the length of 5 μm.