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Group-3 medulloblastoma (MBL) is highly resistant to radiation (IR) and chemotherapy and has the worst prognosis. Hence, there is an urgent need to elucidate targets that sensitize these tumors to chemotherapy and IR. Employing standard assays for viability and sensitization to IR, we identified PRDX1 as a therapeutic target in Group-3 MBL. Specifically, targeting PRDX1 by RNAi or inhibition by Adenanthin led to specific killing and sensitization to IR of Group-3 MBL cells. We rescued sensitization of Daoy and UW228 cells by hypermorphic expression of PRDX1. PRDX1 knockdown caused oxidative DNA damage and induced apoptosis. We correlated PRDX1 expression to patient outcomes in a validated MBL tumor-microarray. Whole genome sequencing identified pathways/genes that were dysregulated with PRDX1 inhibition or silencing. Our in vivo studies in mice employing flank/orthotopic tumors from patient derived xenografts/Group-3 MBL cells confirmed in vitro observations. Animals with tumors in which PRDX1 was targeted by RNAi or Adenanthin (using mini osmotic pumps) showed decreased tumor burden and increased survival when compared to controls. Since, Adenanthin does not cross the blood brain barrier (BBB) we used HAV6 peptide to transiently disrupt the BBB and deliver Adenanthin to the tumor. Immunohistochemistry confirmed that targeting PRDX1 resulted in increased oxidative DNA damage, apoptosis and decreased proliferation. In summary, we have validated PRDX1 as a therapeutic target in group-3 MBL, identified Adenanthin as a potent chemical inhibitor of PRDX1 and confirmed the role of HAV peptide (in the transient modulation of BBB permeability) in an orthotopic model of group-3 MBL.
With the increase in regulations regarding the use of antibiotic growth promoters and the rise in consumer demand for poultry products from ‘Raised Without Antibiotics’ or ‘No Antibiotics Ever’ flocks, the quest for alternative products or approaches has intensified in recent years. A great deal of research has focused on the development of antibiotic alternatives to maintain or improve poultry health and performance. This review describes the potential for the various alternatives available to increase animal productivity and help poultry perform to their genetic potential under existing commercial conditions. The classes of alternatives described include probiotics, prebiotics, synbiotics, organic acids, enzymes, phytogenics, antimicrobial peptides, hyperimmune egg antibodies, bacteriophages, clay, and metals. A brief description of the mechanism of action, efficacy, and advantages and disadvantages of their uses are also presented. Though the beneficial effects of many of the alternatives developed have been well demonstrated, the general consensus is that these products lack consistency and the results vary greatly from farm to farm. Furthermore, their mode of action needs to be better defined. Optimal combinations of various alternatives coupled with good management and husbandry practices will be the key to maximize performance and maintain animal productivity, while we move forward with the ultimate goal of reducing antibiotic use in the animal industry.
We present recent observation results of Sgr A* at millimeter obtained with VLBI arrays in Korea and Japan.
7 mm monitoring of Sgr A* is part of our AGN large project. The results at 7 epochs during 2013-2014, including high resolution maps, flux density and two-dimensional size measurements are presented. The source shows no significant variation in flux and structure related to the G2 encounter in 2014. According to recent MHD simulations by kawashima et al., flux and magnetic field energy can be expected to increase several years after the encounter; We will keep our monitoring in order to test this prediction.
Astrometric observations of Sgr A* were performed in 2015 at 7 and 3.5 millimeter simultaneously. Source-frequency phase referencing was applied and a combined ”core-shift” of Sgr A* and a nearby calibrator was measured. Future observations and analysis are necessary to determine the core-shift in each source.
We show how estimates of parameters characterizing inflation-based theories of structure formation localized over the past year when large scale structure (LSS) information from galaxy and cluster surveys was combined with the rapidly developing cosmic microwave background (CMB) data, especially from the recent Boomerang and Maxima balloon experiments. All current CMB data plus a relatively weak prior probability on the Hubble constant, age and LSS points to little mean curvature (Ωtot = 1.08±0.06) and nearly scale invariant initial fluctuations (ns = 1.03±0.08), both predictions of (non-baroque) inflation theory. We emphasize the role that degeneracy among parameters in the Lpk = 212 ± 7 position of the (first acoustic) peak plays in defining the Ωtot range upon marginalization over other variables. Though the CDM density is in the expected range (Ωcdmh2 = 0.17 ± 0.02), the baryon density Ωbh2 = 0.030 ± 0.005 is somewhat above the independent 0.019 ± 0.002 nucleosynthesis estimates. CMB+LSS gives independent evidence for dark energy (ΩΛ = 0.66 ± 0.06) at the same level as from supernova (SN1) observations, with a phenomenological quintessence equation of state limited by SN1+CMB+LSS to wQ < −0.7 cf. the wQ=−1 cosmological constant case.
A novel nano-scale manipulator capable of handling low-dimensional materials with three-dimensional linear motion, gripping action, and push–pull action of the gripper was developed for an in situ experiment in transmission electron microscopy. X-Y-Z positioning and push–pull action were accomplished by a piezotubing system, combined with a specially designed assembly stage that consisted of a lever-action gripping tip backed by a push–pull piezostack. The gripper tip consisted of tungsten wire fabricated by electrochemical etching followed by a focused ion beam process. Performance of the nano-scale manipulator was demonstrated in a grab-and-pick test of a single silver nanowire and in an in situ tensile test of a pearlitic steel sample with a specific orientation.
Alcohol consumption is a possible co-factor of high-risk human papillomavirus (HR-HPV) persistence, a major step in cervical carcinogenesis, but the association between alcohol and continuous HPV infection remains unclear. This prospective study identified the association between alcohol consumption and HR-HPV persistence. Overall, 9230 women who underwent screening during 2002–2011 at the National Cancer Center, Korea were analysed in multivariate logistic regression. Current drinkers [odds ratio (OR) 2·49, 95% confidence interval (CI) 1·32–4·71] and drinkers for ⩾5 years (OR 2·33, 95% CI 1·17–4·63) had a higher risk of 2-year HR-HPV persistence (HPV positivity for 3 consecutive years) than non-drinkers and drinkers for <5 years, respectively (vs. HPV negativity for 3 consecutive years). A high drinking frequency (⩾twice/week) and a high beer intake (⩾3 glasses/occasion) had higher risks of 1-year (OR 1·80, 95% CI 1·01–3·36) HPV positivity for 2 consecutive years) and 2-year HR-HPV persistence (OR 3·62, 95% CI 1·35–9·75) than non-drinkers. Of the HPV-positive subjects enrolled, drinking habit (OR 2·68, 95% CI 1·10–6·51) and high consumption of beer or soju (⩾2 glasses/occasion; OR 2·90, 95% CI 1·06–7·98) increased the risk of 2-year consecutive or alternate HR-HPV positivity (vs. consecutive HPV negativity). These findings suggest that alcohol consumption might increase the risk of cervical HR-HPV persistence in Korean women.
To modify the rigid structure of alginate, polyvinyl alcohol was mixed. Rheological properties and viscoelastic properties of the polymer blend solution were investigated. Complex and shear viscosity and tangent delta of the solution were obtained to find optimum condition of spinning dope. Effect of blend ratio on morphology and property change was investigated.
InGaN/GaN multi-quantum well (MQW) laser diodes (LDs) were grown on c-plane sapphire substrates using a multi-wafer MOCVD system. The threshold current for pulsed lasing was 1.6 A for a gain-guided laser diode with a stripe of 10 × 800 μm2. The threshold current density was 20.3 kA cm−2 and the threshold voltage was 16.5 V. The optical power ratio of transverse electric mode to transverse magnetic mode was found to be greater than 50. The characteristic temperature measured from the plot of threshold current versus measurement temperature was between 130 and 150K.
Enterotoxigenic Escherichia coli (ETEC) is now recognized as a common cause of foodborne outbreaks. This study aimed to describe the first ETEC O169 outbreak identified in Korea. In this outbreak, we identified 1642 cases from seven schools. Retrospective cohort studies were performed in two schools; and case-control studies were conducted in five schools. In two schools, radish kimchi was associated with illness; and in five other schools, radish or cabbage kimchi was found to have a higher risk among food items. Adjusted relative risk of kimchi was 5·87–7·21 in schools that underwent cohort studies; and adjusted odds ratio was 4·52–12·37 in schools that underwent case-control studies. ETEC O169 was isolated from 230 affected students, and was indistinguishable from the isolates detected from the kimchi product distributed by company X, a food company that produced and distributed kimchi to all seven schools. In this outbreak, we found that the risk of a kimchi-borne outbreak of ETEC O169 infection is present in Korea. We recommend continued monitoring regarding food safety in Korea, and strengthening surveillance regarding ETEC O169 infection through implementation of active laboratory surveillance to confirm its infection.
Although livestock production accounts for a sizeable share of global greenhouse gas emissions, numerous technical options have been identified to mitigate these emissions. In this review, a subset of these options, which have proven to be effective, are discussed. These include measures to reduce CH4 emissions from enteric fermentation by ruminants, the largest single emission source from the global livestock sector, and for reducing CH4 and N2O emissions from manure. A unique feature of this review is the high level of attention given to interactions between mitigation options and productivity. Among the feed supplement options for lowering enteric emissions, dietary lipids, nitrates and ionophores are identified as the most effective. Forage quality, feed processing and precision feeding have the best prospects among the various available feed and feed management measures. With regard to manure, dietary measures that reduce the amount of N excreted (e.g. better matching of dietary protein to animal needs), shift N excretion from urine to faeces (e.g. tannin inclusion at low levels) and reduce the amount of fermentable organic matter excreted are recommended. Among the many ‘end-of-pipe’ measures available for manure management, approaches that capture and/or process CH4 emissions during storage (e.g. anaerobic digestion, biofiltration, composting), as well as subsurface injection of manure, are among the most encouraging options flagged in this section of the review. The importance of a multiple gas perspective is critical when assessing mitigation potentials, because most of the options reviewed show strong interactions among sources of greenhouse gas (GHG) emissions. The paper reviews current knowledge on potential pollution swapping, whereby the reduction of one GHG or emission source leads to unintended increases in another.
The clinical impact of antimicrobial resistance on the outcome of pneumococcal bacteraemia has remained unclear. This study aimed to evaluate risk factors for mortality and determine the impact of antimicrobial resistance on clinical outcomes. A total of 150 adult patients with pneumococcal bacteraemia were identified over a period of 11 years at Seoul National University Hospital. Of the 150 patients, 122 (81·3%) had penicillin-susceptible (Pen-S) strains and 28 (18·7%) penicillin-non-susceptible (Pen-NS) strains; 43 (28·7%) had erythromycin-susceptible (EM-S) strains and 107 (71·3%) erythromycin-non-susceptible (EM-NS) strains. On multivariate analysis, elevated APACHE II score [odds ratio (OR) 1·24, 95% confidence interval (CI) 1·14–1·34, P<0·001) and presence of solid organ tumour (OR 2·99, 95% CI 1·15–7·80, P=0·025) were independent risk factors for mortality. Neither erythromycin resistance nor penicillin resistance had a significant effect on clinical outcomes. However, for the 76 patients with pneumococcal pneumonia, the time required for defervescence was significantly longer in the EM-NS group than in the EM-S group (5·45±4·39 vs. 2·93±2·56, P=0·03 by log rank test). In conclusion, antimicrobial resistance does not have an effect on mortality in adult patients with pneumococcal bacteraemia.
A series of ZnO thin films with various deposition temperatures were prepared on (100) GaAs substrates by radio-frequency magnetron sputtering using ZnO target. The ZnO films were studied by field emission scanning electron microscope(FESEM), x-ray diffraction(XRD), photoluminescence(PL), cathodoluminescence(CL), and Hall measurements. The structural, optical, and electrical properties of the films were discussed as a function of the deposition temperature. With increasing temperature, the compressive stress in the films was released and their crystalline and optical properties were improved. From the depth profile of As measured by secondary ion mass spectrometry(SIMS), As doping was confirmed, and, in order to activate As dopant atoms, post-annealing treatment was performed. After annealing treatment, electrical and optical properties of the films were changed.
Our study describes the synthesis of novel nanoscale Pd cage and wires whose sizes and shapes are templated by mesoporous matrices. The templates used are cubic phase MCM-48 and hexagonal phase CnMCM-41 (n = 16, and 22), SBA-15, which have pore diameters of ∼3, ∼3.8, ∼4.7, and ∼9 nm, respectively. For Pd@MCM-48, the Pd metal forms spherical domains (∼38 nm) consisting of three dimensionally interconnected into Pd arrays; for Pd@SBA-15 and Pd@MCM-41, the Pd metal forms of one-dimensional wires. Etching out the matrix produces porous Pd cages (pore sizes of ∼1.5 - 2.0 nm) with retaining original domain sizes of ∼38 nm; similarly Pd@SBA-15 and Pd@MCM-41 afford freestanding Pd nanowires. All the materials are examined by TEM, XRD, BET, and EDAX analysis. Furthermore, the thermal behavior of Pd nanowire is briefly described.
The relation between the ion irradiation induced grain growth in bilayer system and the basic parameters involved in ion beam mixing process was studied. TEM micrographs showed that a significant grain growth has been induced by Ar+ irradiation at room temperature. The grain size increases rapidly in low dose region, while it approaches a saturated value in high dose region, and it has close relationship with thermodynamic properties such as cohesive energy ( ΔHc ) and heat of mixing( ΔHm ). The experimental results are in good agreement with the model for the grain growth based on the thermal spike induced atomic migration.
This paper presents the recent achievements of ZnO/GaN heteroepitaxy. The general controlling method and mechanism for the polarity of heteroepitaxial ZnO and GaN films by interface engineering via Plasma-assisted Molecular beam epitaxy(P-MBE) are introduced in a viewpoint of principle for polarity control. We propose the principle of crystal polarity: Crystal polarity can succeed at the heterointerface when no interface layer is formed, while an interface layer with inversion symmetry is formed, the crystal polarity is inverted at the heterointerfae. The effects of polarity on the interface, surface and bulk structure, and the structural and optical properties of ZnO/GaN epitaxy are also included. The polarity of GaN on ZnO is successfully controlled based on the proposed principle for control of crystal polarity. Additionally, the electronic characteristics such as electron concentration, band-line-up, and C-V characteristics of ZnO/GaN heterointerface are dicussed.