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A growing number of Korean adolescents consume energy drinks, which may increase the risk of obesity, anxiety and insomnia. We examined whether poor sleep was associated with energy drink consumption among study participants.
We used a cross-sectional design.
The Korea Youth Risk Behavior Web-Based Survey data from 2019.
To determine the association between sleep and energy drink consumption, we compared the independent variables for 50,455 adolescents in Korea (aged 14–19 years) using multivariate logistic regression and sensitivity analyses.
In Korea, 69·5 % adolescents consumed energy drinks, 17·1 % slept for less than 5 h, 22·4 % slept for 5–6 h, 23·8 % slept for 6–7 h, 19·9 % slept for 7–8 h and 16·7 % slept for 8 h or more. Regarding sleep satisfaction, 21·0 % reported sufficient, 32·6 % reported just enough and 46·5 % reported insufficient. Regarding sleep duration, it was found that less than 5 h (OR, 2·36; 95 % CI (2·14, 2·60)) and lower sleep satisfaction (OR, 1·12; 95 % CI (1·03, 1·21)) were highly associated with energy drink consumption, with statistical significance at P < 0·05. Adolescents with lower sleep duration (adjusted OR (aOR), 6·37; 95 % CI (4·72, 8·61)) and a lack of sleep satisfaction (aOR, 1·44; 95 % CI (1·16, 1·78)) reported drinking a high amount of energy drinks, that is, at least once a day.
In addition to efforts to decrease the amount of energy drinks consumed, sleep hygiene education needs to be strengthened.
This study was performed to improve production efficiency at the level of recipient pig and donor nuclei of transgenic cloned pigs used for xenotransplantation. To generate transgenic pigs, human endothelial protein C receptor (hEPCR) and human thrombomodulin (hTM) genes were introduced using the F2A expression vector into GalT–/–/hCD55+ porcine neonatal ear fibroblasts used as donor cells and cloned embryos were transferred to the sows and gilts. Cloned fetal kidney cells were also used as donor cells for recloning to increase production efficiency. Pregnancy and parturition rates after embryo transfer and preimplantation developmental competence were compared between cloned embryos derived from adult and fetal cells. Significantly higher parturition rates were shown in the group of sows (50.0 vs. 4.1%), natural oestrus (20.8 vs. 0%), and ovulated ovary (16.7 vs. 5.6%) compared with gilt, induced and non-ovulated, respectively (P < 0.05). When using gilts as recipients, final parturitions occurred in only the fetal cell groups and significantly higher blastocyst rates (15.1% vs. 21.3%) were seen (P < 0.05). Additionally, gene expression levels related to pluripotency were significantly higher in the fetal cell group (P < 0.05). In conclusion, sows can be recommended as recipients due to their higher efficiency in the generation of transgenic cloned pigs and cloned fetal cells also can be recommended as donor cells through correct nuclear reprogramming.
We report our experience with an emergency room (ER) shutdown related to an accidental exposure to a patient with coronavirus disease 2019 (COVID-19) who had not been isolated.
A 635-bed, tertiary-care hospital in Daegu, South Korea.
To prevent nosocomial transmission of the disease, we subsequently isolated patients with suspected symptoms, relevant radiographic findings, or epidemiology. Severe acute respiratory coronavirus 2 (SARS-CoV-2) reverse-transcriptase polymerase chain reaction assays (RT-PCR) were performed for most patients requiring hospitalization. A universal mask policy and comprehensive use of personal protective equipment (PPE) were implemented. We analyzed effects of these interventions.
From the pre-shutdown period (February 10–25, 2020) to the post-shutdown period (February 28 to March 16, 2020), the mean hourly turnaround time decreased from 23:31 ±6:43 hours to 9:27 ±3:41 hours (P < .001). As a result, the proportion of the patients tested increased from 5.8% (N=1,037) to 64.6% (N=690) (P < .001) and the average number of tests per day increased from 3.8±4.3 to 24.7±5.0 (P < .001). All 23 patients with COVID-19 in the post-shutdown period were isolated in the ER without any problematic accidental exposure or nosocomial transmission. After the shutdown, several metrics increased. The median duration of stay in the ER among hospitalized patients increased from 4:30 hours (interquartile range [IQR], 2:17–9:48) to 14:33 hours (IQR, 6:55–24:50) (P < .001). Rates of intensive care unit admissions increased from 1.4% to 2.9% (P = .023), and mortality increased from 0.9% to 3.0% (P = .001).
Problematic accidental exposure and nosocomial transmission of COVID-19 can be successfully prevented through active isolation and surveillance policies and comprehensive PPE use despite longer ER stays and the presence of more severely ill patients during a severe COVID-19 outbreak.
Cultivated soybeans [Glycinemax (L.) Merr.] have various flower colours such as dark purple, purple, light purple, pink, magenta, near white and white. About one-third of the soybean accessions in the United States Department of Agriculture – Germplasm Resource Information Network (USDA-GRIN) Soybean Germplasm Collections have white flowers and are the second dominant accessions after the purple-flowered accessions. Earlier studies have shown that the w1 recessive allele of the W1 gene encoding flavonoid 3′,5′-hydroxylase produces white flowers. In the present study, we aimed to understand why the white-flowered accessions have become abundant among the cultivated soybeans and what their genetic and regional origin is. For this purpose, 99 landraces with white flowers and 39 landraces with purple flowers from eight Asian countries and Russia were analysed with regard to the nucleotide sequences of the W1 locus. We not only found that the w1 alleles of the 99 white-flowered landraces were identical to those of the white-flowered Williams 82, but also found that these w1 alleles displayed no polymorphism at all. By carrying out a phylogenetic analysis, we were able to identify a group with W1 alleles from which the w1 allele might have diverged.
A method allowing for the stable growth of carbon nanotubes (CNTs) on the surface of a fibrous metal mesh substrate (SUS304) was developed with the assistance of the microwave plasma-enhanced chemical vapor deposition process. The controlled addition of up to ∼13% of O2 to the CH4 plasma reacting gas flow was found to promote the growth of the CNTs by oxidizing the amorphous carbon and removing the active H2 radicals. However, excessive amounts of O2 (i.e., fraction of O2 > ∼13%) and H2 were found to play a negative role in the growth of the CNTs. The control of the density and length of the CNTs was also achieved by varying the H2 plasma reduction time and CH4 plasma reacting time, respectively. Longer H2 reduction pretreatment of the catalytic metal islands resulted in the formation of a less dense CNT forest with craters. When the growth time of the CNTs was increased to ∼20 min, their length was increased to ∼10 μm. However, when the growth time of the CNTs exceeded 20 min, their length was significantly decreased, indicating that the continuous presence of O2 in the CH4 plasma destroys the preformed CNTs due to the oxidation reaction.
The low frequency noise of individual ZnO nanowire (NW) field effect transistors (FETs) exposed to air is systematically characterized. The measured noise power spectrum shows a classical 1/f type. The noise amplitude is independent of source-drain current and inversely proportional to gate voltage. The extracted Hooge's constant of ZnO NW is found to be 6.52×10−3. In addition, the low frequency noise of ZnO NW according to NW resistance and contact property are investigated. The noise amplitude is proportional to the square of ZnO NW resistance. If a sample shows a nonlinear current-voltage (I-V) characteristic due to a poor electrical contact, the noise power spectrum is proportional to the third power of current instead of the square of current.
Field effect transistors(FETs) made of ZnO nanowires are very sensitive to the gas environment, so that the passivation can be a good way to get reliable nanowire FETs with longer lifetime and the better mobility. The studies on the passivation effects with the positive electron-beam resist was investigated by selectively covering the part of nanowire devices between the electrodes. Reproducible electrical characteristics were recorded, reflecting the stable electrical properties by the passivation which deters the degradation of a device. Considering the defect states of oxide nanowires dominate the charge states, the pre-state just before the passivation process will be crucial to understand the reproducible and controllable device characteristics of nanowire devices.
Organic thin film transistors(OTFTs) were simulated by a SPICE model adopted in hydrogenated amorphous TFTs(a-Si:H). The gate voltage-dependent mobilities were assumed to fit the representative current-voltage characteristics. The optimal fitting procedures were suggested to compare the experimental data with the mathematical expressions used in the amorphous TFTs. Each SPICE parameter explains the gate dependent mobilities in OTFTs originating from the distribution of trap sites for the hopping conduction.
Bonding process using indium-silver alloy which can withstand high temperature was investigated at relatively low temperature. We used a thermal evaporator and vacuum coater for making indium-silver contact. From the result of experiment, we observed that indium and silver films which have good quality are formed. From phase diagram of In-Ag alloy, we can find that melting point of these compounds increases with the silver content, i.e. eutectic (144° C) <AgIn2 (166° C) < (300° C) < (670° C) < (695° C). And these compounds are determined by the composition ratio of the source metal. Now we confirmed the thermal characteristics of Indium-Silver alloy is controlled by silver. Consequently we have developed Ag/In/Ag multi-layer composite which has higher melting point than that of normal contact. The melting point of Ag/In/Ag multi-layer is about 700° C. The joint cross-sections are studied using SEM(scanning electron microscopy) and EDX(Energy Dispersive X-rays). From these data, we observed that the composition and microstructure of Ag/In/Ag multi-layer were reliable and this bonding procedure is a better technique compared to the conventional structure of quantum well LED and GaN/Si LED structure was made by using sapphire for substrate and might be good for high temperature electronic devices in the future.
To test the hypothesis that the availability of glucose or its precursors can
influence the response of milk protein concentration to the intravenous infusion of
amino acids, five cows were used in a 5 × 5 Latin square design with period lengths
of 7 d. The five treatments were the basal diet of grass silage ad lib. plus 5 kg/d of a
cereal-based supplement containing feather meal (Basal); Basal plus 4 g/d histidine,
8 g/d methionine and 26 g/d lysine (4H); Basal plus 8 g/d histidine, 8 g/d methionine
and 26 g/d lysine (8H); and these two amino acid mixtures together with 600 g/d of
glucose (4HG and 8HG respectively). Earlier experiments with this basal diet had
shown that histidine was first-limiting for secretion of milk protein, followed by
methionine and lysine. The yield of milk protein was increased progressively with the
amount of histidine infused. The efficiency of transfer of histidine into milk protein
was 0·42 for the 4H and 4HG and 0·35 for the 8H and 8HG treatments, and the
concentration of milk protein was increased over Basal by all infusion treatments.
However, milk protein concentrations were higher, and lactose concentrations in the
milk were lower, in the absence of added glucose. Concentrations of insulin in blood
plasma were not affected by treatment. It is concluded that, with the treatments
without added glucose, a shortage of glucose prevented an increase in lactose
secretion, and hence limited the increase in milk yield, leading to an increased
concentration of protein in the milk.
V2O5 nanofibers showed the rectifying current-voltage characteristics under an asymmetric contact configuration at room temperature, indicating the formation of a Schottky diode. The ideality factors as a Schottky diode were estimated to be 6.1 at the forward bias and 1.4 at the reverse bias. The larger current at the reverse bias defined by the negative voltage at the metal electrode may originate from the contribution of the tunneling via field emission or thermionic field emission. The ultimate geometric size of nanofibers enhances the influence of the tunneling mechanism and modifies the nano-scale Schottky diode, requiring more understanding in designing the nano-scale electronic devices with the metal contacts.
The transport of L-glutamine by the lactating rat mammary
been investigated using rat mammary tissue explants and the in situ
mammary gland. L-glutamine uptake by both explants and the perfused
gland was via both Na+-dependent and Na+-independent
pathways. It appeared that
these pathways are situated on the blood-facing aspect of the mammary gland.
L-glutamine uptake by both mammary preparations was markedly inhibited
2-aminobicyclo[2,2,1]heptane-2-carboxylic acid in the absence
Na+. This is consistent with L-glutamine uptake via
system L. The
of L-glutamine uptake remains to be precisely identified. However,
system A can be
ruled out on the basis that L-glutamine was not inhibited by (methylamino)isobutyric
acid. Mammary tissue concentrates L-glutamine with respect to
both milk and
plasma: we suggest that the Na+-dependent component(s)
of L-glutamine uptake is
responsible for generating the intracellular to extracellular concentration
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