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Seasonal influenza virus epidemics have a major impact on healthcare systems. Data on population susceptibility to emerging influenza virus strains during the interepidemic period can guide planning for resource allocation of an upcoming influenza season. This study sought to assess the population susceptibility to representative emerging influenza virus strains collected during the interepidemic period. The microneutralisation antibody titers (MN titers) of a human serum panel against representative emerging influenza strains collected during the interepidemic period before the 2018/2019 winter influenza season (H1N1-inter and H3N2-inter) were compared with those against influenza strains representative of previous epidemics (H1N1-pre and H3N2-pre). A multifaceted approach, incorporating both genetic and antigenic data, was used in selecting these representative influenza virus strains for the MN assay. A significantly higher proportion of individuals had a ⩾four-fold reduction in MN titers between H1N1-inter and H1N1-pre than that between H3N2-inter and H3N2-pre (28.5% (127/445) vs. 4.9% (22/445), P < 0.001). The geometric mean titer (GMT) of H1N1-inter was significantly lower than that of H1N1-pre (381 (95% CI 339–428) vs. 713 (95% CI 641–792), P < 0.001), while there was no significant difference in the GMT between H3N2-inter and H3N2-pre. Since A(H1N1) predominated the 2018–2019 winter influenza epidemic, our results corroborated the epidemic subtype.
The oriental armyworm, Mythimna separata is an important crop pest in eastern Asia. Nocturnal insects, including nocturnal moths, have phototactic behavior to an artificial light source. Phototactic behavior in insects is species-specific in response to different wavelengths of light sources. Our previous study showed that green (520 nm) light emitting diode (LED) light resulted in a significantly higher phototactic behavior in M. separata moths compared to the other wavelength LED lights. The goal of the present study is to investigate the influence of green light illumination on biological characteristics of different developmental stages in M. separata. Our results revealed that when different developmental stages of M. separata were exposed to the green light illumination in a dark period, several biological characteristics in all developmental stages except for egg stage were positively changed, but those of F1 generation M. separata which are next generation of the adults exposed to the green light did not significantly change compared with the control level. These findings suggest that green light illumination at night (or dark period) has a positive effect on the development and longevity of M. separata.
Vitamin E and selenium have been reported to improve immune function across a range of species. Ewes lambing on poor-quality dry pasture in autumn in Western Australia are at risk of being deficient in vitamin E and selenium at lambing thus predisposing their lambs to deficiencies and increasing the risk of infection and disease. This study tested the hypotheses that (i) supplementation of autumn-lambing ewes with vitamin E plus selenium in late gestation will increase the concentrations of vitamin E and selenium in plasma in the ewe and lamb and (ii) that the increased concentrations of vitamin E and selenium in plasma in the lambs will improve their innate and adaptive immune responses and thus survival. Pregnant Merino ewes were divided into a control group (n=58) which received no supplementation or a group supplemented with vitamin E plus selenium (n=55). On days 111, 125 and 140 of pregnancy ewes in the vitamin E plus selenium group were given 4 g all-rac-α-tocopherol acetate orally. On day 111 the ewes were also given 60 mg of selenium as barium selenate by subcutaneous injection. The concentrations of α-tocopherol and selenium were measured in ewes and/or lambs from day 111 of pregnancy to 14 weeks of age±10 days (weaning). Immune function of the lamb was assessed by analysing the numbers and phagocytic capacities of monocytes and polymorphonuclear leucocytes and plasma IgG and anti-tetanus toxoid antibody concentrations between birth and 14 weeks of age±10 days. Maternal supplementation with vitamin E plus selenium increased the concentration of α-tocopherol in plasma (1.13 v. 0.67 mg/l; P<0.001) and selenium in whole blood (0.12 v. 0.07 mg/l; P<0.01) of the ewes at lambing compared with controls. Supplementation also increased the concentration of α-tocopherol (0.14 v. 0.08 mg/l; P<0.001) and selenium (0.08 v. 0.05 mg/l; P<0.01) in lambs at birth compared with controls. There was no significant effect of supplementation on immune function or survival in the lambs.
To study the clinical effect of lens cleaning paper patching on traumatic eardrum perforations.
A total of 122 patients were divided into 2 groups, of which 56 patients were treated with lens cleaning paper patching and 66 acted as controls. The closure rate and healing time were compared between the two groups.
The healing rate of small perforations was 96.4 per cent (27 out of 28) in the patching group and 90 per cent (27 out of 30) in the control group. The difference was not statistically significant (p > 0.05). The healing rate of large perforations was 89.3 per cent (25 out of 28) and 80.6 per cent (29 out of 36) in the two groups, respectively. The difference was statistically significant (p < 0.05). The healing time of large perforations was shorter in the patching group than in the control group (p < 0.01).
Patching with lens cleaning paper under an endoscope can accelerate the closure of large traumatic eardrum perforations.
Dietary cholesterol induces hepatic inflammation and fibrosis in animals. We aimed to determine whether dietary cholesterol affects liver-related mortality in hepatitis C virus (HCV)-infected patients. We performed a retrospective cohort study using extended follow-up data from the Hepatitis C Antiviral Long-Term Treatment Against Cirrhosis Trial. The study included HCV patients with advanced fibrosis and compensated cirrhosis. The analysis included 657 patients who completed two FFQ. We assessed whether cholesterol intake, measured in mg/4184 kJ (mg/1000 kcal) of energy intake, was associated with liver-related death or transplantation. In 4·7 (sd 1·6) years, the incidence of liver-related death (n 46) or transplantation (n 52) was 31·8/1000 person-years. The relationship between cholesterol intake and liver-related death or transplantation was significantly different between men and women (test for interaction, P value=0·01). Each higher quartile of cholesterol intake was associated with an increased risk for liver-related death or transplantation in women (adjusted hazard ratio (AHR) 1·83; 95 % CI 1·12, 2·99; Ptrend=0·02), but not in men (AHR 0·96; 95 % CI 0·76, 1·22; Ptrend=0·73). Compared with women whose cholesterol intake was within the recommended guidelines (300 mg/d with a 8368 kJ (2000 kcal) diet), women who consumed more cholesterol had significantly increased risk for liver-related death or transplantation (AHR 4·04; 95 % CI 1·42, 11·5). High dietary cholesterol was associated with an increased risk for liver-related death and transplantation in HCV-infected women with advanced fibrosis or compensated cirrhosis. Future studies should assess whether reducing cholesterol intake, among women who consume an excessive amount, can decrease HCV-related mortality.
We recently fabricated and characterized a new class of multilayer dielectric elastomer films comprising alternating layers of two different polymers, at least one of which is an elastomer. The films discussed here contain THV (a terpolymer of poly(vinylidene fluoride)) and poly(ethylene octene) [EO] elastomer. The multilayer structure provides improved dielectric and electromechanical performance relative to monolithic films of THV or EO. These properties are controlled by the composition and the layer structure. For example, increasing the concentration of the elastomeric EO component increases the maximum axial strain (sz). Layering EO with THV also increases the breakdown strength (EB ∼ 265 - 300 V/µm) relative to monolithic EO (EB ∼ 150 V/µm) or THV (EB ∼ 245 V/µm) control films. This enhancement in breakdown strength is consistent with a barrier effect that is also observed in multilayer polymer capacitor films. The increase in breakdown strength allows 512-layer 75 vol% EO / 25 vol% THV films to achieve maximum axial strains of sz nearly 4%, higher than can be attained by either EO or THV films alone. In addition, layering reduces remnant strain and electromechanical hysteresis by limiting the effective field within the THV layers. The 75% EO/ 25% THV films show robust operational longevity with little loss in axial strain when subjected to repeated actuation at Emax = 225 V/µm (producing sz = 2.2%). Under these conditions, we observe 3,000 consecutive actuation cycles with no electrical breakdown. In comparison, single component EO control films undergo electrical breakdown at this field and THV control films survive only a few hundred actuation cycles under these conditions. The results demonstrate that multilayering is an effective technique to increase the dielectric strength of elastomer materials and in turn improve upon strain and operational longevity (repeated actuation cycles) characteristics.
For the gate last approach of a high K metal gate scheme used in advanced CMOS technology, various materials were tested as wetting layers to allow Aluminum (Al) gap fill at gate widths of10 to 45 nanometers. In this study, Titanium (Ti) and Cobalt (Co) were investigated as a wetting layer for Al gap fill. It was discovered that Al-Ti and Al-Co alloys were formed during high temperature Al deposition. Alloys were characterized using XRD. Alloy’s impacts on line resistivity and subsequent Al Chemical Mechanical Polish (Al CMP) were also investigated. In addition, a model was established to predict the alloy type and alloy mole% with respect to feature size. The predicted Al mole% by this model correlated very well with 1) line resistivity trend and 2) morphologies. The model also predicted that due to Al lower electro-chemical potential than Ti, Co or its alloys, galvanic corrosion could take place depending on the chemical environment in the Al CMP slurry. Different slurry or cleaning chemical may reduce or increase the risk of galvanic corrosion. The knowledge gained with the help of the model provides clear directions on selection criteria for wetting layers, optimization for deposition processes and Al CMP consumable design to meet the challenges.
This study describes the elimination of threading dislocations (TDs) in GaN nanostructures. Cross-sectional transmission electron microscopy (XTEM) analysis reveals that the nominal  line direction of a TD changes when it enters a GaN nanostructure and the dislocation then terminates at a sidewall facet. It is suggested that the driving force for this process is the reduction of dislocation line energy, and for a pure-edge dislocation, this TD elimination process can be accomplished simply by dislocation climb. This mechanism is active whenever a threading defect is in close proximity to a surface. Preliminary XTEM analysis of defects in AlGaN and InGaN core–shell growth onto GaN nanostructures is also shown. Although more work is required to improve the quality of core–shell InGaN epitaxial growth, nanostructures appear to offer a route to defect-free, nonpolar GaN-based devices.
Surface treatment of polymer films is
usually necessary to improve surface wetting and adhesion characteristics.
Traditional liquid chemical processes have several disadvantages in contrast
to dry finishing processes, like plasma technology. Dielectric barrier
discharges at atmospheric pressure are extensively studied for surface
treatment, however, almost no research has been done on surface treatment
with a dielectric barrier discharge at medium pressure. Therefore, in this
paper, a polypropylene (PP) film is plasma-treated with a dielectric barrier
discharge (DBD) in nitrogen at medium pressure (5.0 kPa). The surface
properties of the plasma-treated samples are examined using contact angle
measurements, X-ray photoelectron spectroscopy (XPS) and atomic force
microscopy (AFM). Results show that the surface wettability is significantly
enhanced after plasma treatment. The incorporation of nitrogen on the
surface is significant (10 at%), demonstrating the ability of the used
DBD set-up to generate nitrogen-containing functional groups on the PP
surface. Nevertheless, a considerable amount of oxygen (10 at%) is
incorporated onto the PP surface underlining the extreme reactivity of
oxygen active species and the difficulty in overcoming the air contamination
problem. Moreover, AFM analysis reveals that the nitrogen plasma creates
large changes in the surface morphology of the PP film due to the selective
etching of the amorphous regions of the polymer film.
Control of the low-temperature sintering of nanosilver particles was attained by dispersing and stabilizing nanosilver particles into a paste form using the selected organic binder systems. As demonstrated by scanning electron microscopy (SEM) and thermogravimetric analysis (TGA), with the existing binder systems, undesirable premature coalescence of nanosilver particles was prevented and the metastable structure was retained until the binder burned out at relatively higher temperatures. Enhanced densification was achieved upon the binder burnout because at the relatively higher temperatures the densification mechanisms, e.g., grain-boundary or lattice diffusion, become more dominant. We propose that the onset of sintering, extent of densification, and final grain size can be controlled by either the size of the initial nanosilver particles or the binder systems with different burnout characteristics.
In2O3 nanowire and carbon nanotube transistors were used to study the chemical gating effects in response to LDL particles. Low density lipoprotein (LDL) cholesterol in blood constitutes a risk factor for coronary artery disease (heart attack). The interactions of LDL particles with these two different surfaces were investigated. The degree of LDL particles binding to carbon nanotubes was ten-fold higher than to In2O3 nanowires possibly owing to the hydrophobic/hydrophilic interactions. The conductance of field effect transistors (FET) based on nanowires and nanotubes showed complementary responses after exposure to LDL particles. While In2O3 nanowire transistors exhibited higher conductance accompanied by a negative shift of the threshold voltage, nanotube transistors displayed a lower conductance. This phenomenon was attributed to the complementary doping between the n-type In2O3 nanowires and p-type carbon nanotubes.
High-density and high-quality single walled carbon nanotubes are directly grown on surface by Chemical Vapor Depositions. We found that those SWNT thin films could be used to fabricate thin film field-effect transistors. Those transistors are very sensitive to surface charges changes in aqueous solutions and could be used tobuild chemical sensors.