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The present study investigated the association between fibre degradation and the concentration of dissolved molecular hydrogen (H2) in the rumen. Napier grass (NG) silage and corn stover (CS) silage were compared as forages with contrasting structures and degradation patterns. In the first experiment, CS silage had greater 48-h DM, neutral-detergent fibre (NDF) and acid-detergent fibre degradation, and total gas and methane (CH4) volumes, and lower 48-h H2 volume than NG silage in 48-h in vitro incubations. In the second experiment, twenty-four growing beef bulls were fed diets including 55 % (DM basis) NG or CS silages. Bulls fed the CS diet had greater DM intake (DMI), average daily gain, total-tract digestibility of OM and NDF, ruminal dissolved methane (dCH4) concentration and gene copies of protozoa, methanogens, Ruminococcus albus and R. flavefaciens, and had lower ruminal dH2 concentration, and molar proportions of valerate and isovalerate, in comparison with those fed the NG diet. There was a negative correlation between dH2 concentration and NDF digestibility in bulls fed the CS diet, and a lack of relationship between dH2 concentration and NDF digestibility with the NG diet. In summary, the fibre of CS silage was more easily degraded by rumen microorganisms than that of NG silage. Increased dCH4 concentration with the CS diet presumably led to the decreased ruminal dH2 concentration, which may be helpful for fibre degradation and growth of fibrolytic micro-organisms in the rumen.
Staff surveillance is crucial during the containment phase of a pandemic to help reduce potential healthcare-associated transmission and sustain good staff morale. During an outbreak of SARS-COV-2 with community transmission, our institution used an integrated strategy for early detection and containment of COVID-19 cases among healthcare workers (HCWs).
Our strategy comprised 3 key components: (1) enforcing reporting of HCWs with acute respiratory illness (ARI) to our institution’s staff clinic for monitoring; (2) conducting ongoing syndromic surveillance to obtain early warning of potential clusters of COVID-19; and (3) outbreak investigation and management.
Over a 16-week surveillance period, we detected 14 cases of COVID-19 among HCWs with ARI symptoms. Two of the cases were linked epidemiologically and thus constituted a COVID-19 cluster with intrahospital HCW–HCW transmission; we also detected 1 family cluster and 2 clusters among HCWs who shared accommodation. No transmission to HCWs or patients was detected after containment measures were instituted. Early detection minimized the number of HCWs requiring quarantine, hence preserving continuity of service during an ongoing pandemic.
An integrated surveillance strategy, outbreak management, and encouraging individual responsibility were successful in early detection of clusters of COVID-19 among HCWs. With ongoing local transmission, vigilance must be maintained for intrahospital spread in nonclinical areas where social mingling of HCWs occurs. Because most individuals with COVID-19 have mild symptoms, addressing presenteeism is crucial to minimize potential staff and patient exposure.
Much effort has been devoted to improving the efficiency of animal cloning. The aim of this study was to investigate the effect of BRG1 contained in Xenopus egg extracts on the development of cloned mouse embryos. The results showed that mouse NIH/3T3 cells were able to express pluripotent genes after treatment with egg extracts, indicating that the egg extracts contained reprogramming factors. After co-injection of Xenopus egg extracts and single mouse cumulus cells into enucleated mouse oocytes, statistically higher pronucleus formation and development rates were observed in the egg Extract− co-injected group compared with those in the no egg extract-injected (NT) group (38–66% vs 18–34%, P<0.001). Removal of BRG1 protein from Xenopus egg extracts was conducted, and the BRG1-depleted extracts were co-injected with single donor cells into recipient oocytes. The results showed that the percentages of pronucleus formation were significantly higher in both BRG1-depleted and BRG1-intact groups than that in the nuclear transfer (NT) group (94, 64% vs 50%, P<0.05). Furthermore, percentages in the BRG1-depleted group were even higher than in the BRG1-intact group (94% vs 64%). More confined expression of Oct4 in the inner cell mass (ICM) was observed in the blastocyst derived from the egg extract-injected groups. However, Nanog expression was more contracted in the ICM of cloned blastocysts in the BRG1-depleted group than in the BGR1-intact group. Based on the present study, BRG1 might not play an essential role in reprogramming, but the factors enhancing pronucleus formation and development of cloned mouse embryos are contained in Xenopus egg extracts.
The hydroxyapatite nanoparticles (nHAPs) were synthesized rapidly by the self-assembled dual-frequency ultrasonic method. The ultrasonic time and power effect on the morphology and phase composition of nHAPs were investigated through field-emission scanning electron microscopy (FE-SEM), X-ray diffraction, energy dispersive spectrometer (EDS) spectrometer, and Fourier transform infrared spectroscopy, which showed that the most uniform nanoparticles were obtained when the ultrasonic time was 30 min and the ultrasonic power was 280 W. Cytotoxicity and hemolysis tests showed that an indistinctive cytotoxic effect was within the concentration of 25–400 μg/mL and the hemolytic ratio was below 2.0% at concentration of 25–200 μg/mL, respectively, revealing a good biocompatibility of nHAPs. By loading tetracycline hydrochloride onto nHAPs spheres, the drug release results showed that the drug loading and encapsulation efficiency were (26.34 ± 2.99)% and (52.68 ± 5.98)%, respectively. The drug-loaded sample shows a slow-release property, indicating that nHAPs may be promising as drug carriers.
This article revisits the issue of the offshore islands in the Taiwan Strait during the Cold War. Benefitting from archival materials only recently made available, specifically Chiang Kai-shek's personal diaries, CIA declassified materials, Taiwanese Foreign Ministry files, and rare publications from the Contemporary Taiwan Collection at the Library of the Institute of Oriental Culture, University of Tokyo, this research examines the cloud of suspicion surrounding the secret contacts between Taipei and Beijing leading up to and during the 1958 offshore islands crisis, elucidating how such a political tête-à-tête, and the resultant tacit consensus over the status of the islands, gradually brought about an end to the conflict between Taiwan and Communist China. In hindsight, the crises over the offshore islands along China's southeast coast momentarily brought the United States closer to war with Communist China, while putting the relationship between Taipei and Washington to a serious test. The end result, however, was that, while these isles were technically embedded in the unfinished civil war between the Chinese Nationalists and Communists, they provided, ironically, an opportunity for secret communications and, ultimately, a kind of détente between the two supposedly deadly enemies across the Taiwan Strait. A close examination of the details of these crises, along with their attendant military, political, and diplomatic complexities, reveals an amazing amount of political intrigue at both the local and international levels that has not been fully realized until now.
Ubiquinone is a lipid antioxidant, and a novel liquid ubiquinol (a hydro-soluble, reduced form of coenzyme Q10) supplement was recently developed. The purpose of this study was to examine the levels of glucose, lipids and antioxidant capacity of type 2 diabetes patients after liquid ubiquinol supplementation. This study was designed as a randomised, double-blind, placebo-controlled trial. In all, fifty participants were randomly assigned to a placebo (n 25) or liquid ubiquinol (100 mg/d, n 25) group, and the intervention lasted for 12 weeks. Plasma coenzyme Q10, glucose homoeostasis parameters, lipid profiles, oxidative stress and antioxidative enzyme activities were measured during the study. After 12 weeks of supplementation, glyco Hb (HbA1c) value was significantly decreased in the liquid ubiquinol group (P=0·03), and subjects in the liquid ubiquinol group had significantly lower anti-glycaemic medication effect scores (MES) compared with those in the placebo group (P=0·03). The catalase (P<0·01) and glutathione peroxidase (P=0·03) activities were increased significantly after supplementation. Plasma coenzyme Q10 was correlated with the insulin level (P=0·05), homoeostatic model assessment-insulin resistance (P=0·07), quantitative insulin sensitivity check index (P=0·03) and the anti-hyperglycaemic agents’ MES (P=0·03) after supplementation. Lipid profiles did not change after supplementation; however, the subjects in the placebo group had a significantly lower level of HDL-cholesterol after 12 weeks of intervention. In conclusion, oral intake of 100 mg/d liquid ubiquinol might benefit type 2 diabetes patients by increasing antioxidant enzyme activity levels, reducing HbA1c levels and maintaining HDL-cholesterol levels.
Attention-deficit hyperactivity disorder (ADHD) increases the risk of suicidal behaviours through psychiatric comorbidities; however, a significant direct association has not been observed between ADHD and suicide attempts.
To evaluate the risk of suicide attempt in adolescents and young adults with ADHD.
Using a nationwide, population-based insurance claims database, this longitudinal cohort study enrolled 20 574 adolescents and young adults with ADHD and 61 722 age- and gender-matched controls between 2001 and 2009. Any suicide attempt was identified from enrolment to 31 December 2011. The association between ADHD medications and the likelihood of suicide attempt was assessed.
ADHD was an independent risk factor for any suicide attempt (hazard ratio = 3.84, 95% CI = 3.19–4.62) and repeated suicide attempts (hazard ratio = 6.52, 95% CI = 4.46–9.53). Subgroup analyses of men, women, adolescents and young adults demonstrated the same trend. Methylphenidate or atomoxetine treatment did not increase the risk of suicide attempt or repeated suicide attempts. Long-term methylphenidate treatment was associated with a significantly decreased risk of repeated suicide attempts in men (hazard ratio = 0.46, 95% CI = 0.22–0.97).
ADHD was a risk factor for suicide attempt and a stronger predictor of repeated suicide attempts, independent of comorbidities. Further investigation is warranted to explore the mechanism underlying the association between ADHD and suicidal behaviours.
Fluazifop-P-butyl, a selective graminicide, has been widely used to control annual grass weeds for more than three decades in Taiwan, and a resistant (R) biotype of goosegrass has consequently appeared. In this study, liquid chromatography/tandem mass spectrometry (LC/MS/MS) was applied to analyze metabolites of fluazifop-P-butyl in a R biotype of goosegrass. Six signals, including mass-to-charge ratios (m/z) 512, 432, 423, 415, 314, and 160, in positive scanning mode, and four signals, including m/z 788, 623, 593, and 162, in negative scanning mode, were found in the metabolites of the R and S biotypes, respectively. All of the signals of these metabolites in the R biotype showed higher intensity than those of the S biotype, except for m/z 162. Based on the molecular weights of the fragments (MS2 signal) from the molecules (MS1 signal) and comparison with the Metabolite Link Metabolomics database, MassBank database, and related references, one reduced form of fluazifop acid, i.e., 2-[4-(5- trifluoromethyl-2-pyridyloxy) phenoxy] propanol (MW 313); two types of intermediates of MW 163, i.e., 5-trifluoromethyl-2-pyridone and 5-trifluoromethyl-2-hydroxypyridine (or 2-hydroxy-5-trifluoromethyl pyridine); and five possible conjugated compounds containing a common core fragment (MW 255) from fluazifop acid were identified. In addition, another compound, likely degraded from one of the five conjugated compounds, was also detected. Accordingly, the metabolic pathway of fluazifop-P-butyl in goosegrass is described in this study. An enzyme kinetic study on glutathione S-transferase showed that the R biotype has higher affinities to the substrates reduced glutathione (GSH) and 1-chloro-2, 4-dinitrobenzene, with S/R Km ratios of 3.0 and 2.4, respectively. No difference in Vmax was found, revealing that the S biotype has a strong ability to bind GSH and herbicide or target molecules and showed susceptibility to fluazifop.
In this paper, we consider two innovative structured matrices, CUPL-Toeplitz matrix and CUPL-Hankel matrix. The inverses of CUPL-Toeplitz and CUPL-Hankel matrices can be expressed by the Gohberg-Heinig type formulas, and the stability of the inverse matrices is verified in terms of 1-, ∞- and 2-norms, respectively. In addition, two algorithms for the inverses of CUPL-Toeplitz and CUPL-Hankel matrices are given and examples are provided to verify the feasibility of these algorithms.
The Lorentz factor (Γ) is an important parameter related to the relativistic jet physics. We study the evolution patterns of Γ within gamma-ray burst (GRB) and active galactic nuclear jets for individual GRB 090168, GRB 140508A, and 3C 454.3. By estimating the Γ values for well-separated pulses in GRBs 090618 and 140508A with an empirical relation derived from typical GRBs, we find that the Γ evolution pattern in the two GRBs are different. The increasing-to-coasting evolution pattern of Γ in GRB 090618 likely indicates that the GRB fireball is still being accelerated in the prompt phase. The clear decrease evolution pattern of Γ in GRB 140508A suggests the deceleration of the fireball components. By deriving the Γ value through fitting their spectral energy distribution in different flares of 3C 454.3, a pattern of Γ-tracking-γ-ray flux is clearly found, likely indicating that the observed gamma-ray flares are being due to the Doppler boosting effect to the jet emission.
A novel radio frequency identification tag antenna is composed of a resonant open-slot exciter and a dipole-type ground radiator. For a conjugate match to the Alien Higgs-4 chip impedance of 8−j149 Ω at 925 MHz, a quarter wavelength open-slot resonator embedded at the center of the dipole-type ground plane (130 × 18 mm2) was investigated and fabricated. Simple size adjustments and various loaded inductor of the open-slot resonator allow for easy control of the tag antenna resistance and inductive reactance, from which the chip impedance requirement can be easily obtained. The read range of the prototype antenna attached on a foam in the free space can reach more than 9 m, which has been tested for a radio frequency identification reader with 4.0-W of effective isotropic radiated power. Measurement data are in good agreement with simulation results.
In contrast to voice traffic, wireless data traffic is mostly asymmetric and time-variant with a requirement for a dynamically adjusting technique to divide the uplink (UL) and downlink (DL) resource. In typical cellular systems, the length of UL resource and the length of DL resource are predetermined. In a typical frequency-division duplex (FDD) system, the UL and DL transmission use distinctive frequency bands, which is especially efficient in cases of symmetric traffic due to the avoidance of possible interference between UL and DL transmission. However the FDD system has difficulty in adjusting its UL and DL resource in asymmetric traffic since the resource division is operated by the duplexer in the hardware. A typical time-division duplex (TDD) system is capable of adjusting the UL and DL transmission in time domain. However, due to the requirement of synchronization in order to eliminate the interference, the UL and DL resource is still fixed. To support asymmetric and time-variant traffic, LTE provides small cell base stations (BSs) with dynamic TDD by supporting seven TDD UL/DL configurations, enabling the BSs dynamically to change the ratio of UP and DL resource to handle the time-variant traffic. Nevertheless, such a scheme also induces two type of interference: BS–BS interference and MS–MS interference. In this chapter the interference issues and several interference mitigation methods will be extensively discussed.
Dynamic TDD system overview
To divide the UL and DL traffic resource, some typical communication systems apply FDD, where different frequency bands are used for transmitting and receiving, the benefit of which is that no interference will be incurred between UL and DL signals. For the symmetrical traffic on UL and DL (e.g., voice service), the FDD system is suitable since the BS is assigned the same amount of radio resource in the UL and DL. Whereas for wireless data services, FDD is not flexible enough to handle this type of dynamic UL/DL traffic due to the character of the UL and DL traffic being asymmetric and time-variant in these cases.
Compared to FDD, TDD is different in that the UL and DL resource is divided in time domain and can be easily adjusted. It possesses an advantage of greater flexibility in handling the dynamic UL/DL traffic. In the TDD system, the boundary between the UL and DL duty cycle is adaptively adjustable according to service requirements.
Many studies have suggested that folate-related one-carbon metabolism-related nutrients may play a role in certain cancer risks, but few studies have assessed their associations with the risk for nasopharyngeal carcinoma (NPC). In this study, we investigated the association between four folate-related one-carbon metabolism-related nutrients (folate, vitamin B6, vitamin B12 and methionine) and NPC risk in Chinese adults. A total of 600 patients newly diagnosed (within 3 months) with NPC were individually matched with 600 hospital-based controls by age, sex and household type (urban v. rural). Folate, vitamin B6, vitamin B12 and methionine intakes were measured using a validated seventy-eight-item FFQ. A higher dietary folate or vitamin B6 intake was associated with a lower NPC risk after adjusting for potential confounders. The adjusted OR of NPC for quartiles 2–4 (v. 1) were 0·66 (95 % CI 0·48, 0·91), 0·52 (95 % CI 0·37, 0·74) and 0·34 (95 % CI 0·23, 0·50) (Ptrend<0·001) for folate and 0·72 (95 % CI 0·52, 1·00), 0·55 (95 % CI 0·39, 0·78) and 0·44 (95 % CI 0·30, 0·63) (Ptrend<0·001) for vitamin B6. No significant association with NPC risk was observed for dietary vitamin B12 or methionine intake. The risk for NPC with dietary folate intake was more evident in the participants who were not exposed to toxic substances than in those who were exposed (Pinteraction=0·014). This study suggests that dietary folate and vitamin B6 may be protective for NPC in a high-risk population.
A 0.18 µm CMOS Binary Frequency Shift Keying Modulator with a novel frequency synthesizer structure is proposed in this paper. Based on an analog adder technique being the backbone of the synthesizer, this prototype demonstrates a compact modulator with low complexity, which achieves 1 Mbps at 400 MHz while dissipating 3.1 mW at 1.5 V supply. The proposed design is ideal for biomedical sensor network systems including distributed wearable body area network.
Biomolecular detection is crucial from various perspectives, such as quality
control of our food and water, identification of biological terrorist
agents, and diagnosis of diseases. Early detection of disease is important
for effective treatment and for prognostic assessment of disease
progression; in addition, the trend of ageing societies leads to an
increasing requirement for biomarker diagnoses for personalized healthcare
monitoring. This results in more stress on the social healthcare system [1,
2]. As a consequence, researchers have focused on developing biomolecular
detection devices and systems. Over the past decade, emerging methods to
address the above needs have bloomed because of developments in
micro/nanotechnologies. To enhance throughputs and reduce costs,
moreover, these detection devices and systems are evolving from label-based
to label-free technologies.
Traditionally, label-based molecular diagnosis techniques have been used as a
useful fundamental concept for the detection of potential disease biomarkers
or pathogen nucleic acids. In general, the detection signal comes from the
usage of a specific tag for a target molecule. The tags can be conventional
fluorescent dyes or radioisotopes. To fulfill the requirements of different
applications, a number of conventional label-based techniques, such as
polymerase chain reaction (PCR), DNA or protein microarrays, and
enzyme-linked immunosorbent assay (ELISA), have been developed and
implemented. Some of them have been used to form a versatile platform for
many diverse applications with promising results and represent the gold
standards of biomedical diagnosis [3–5]. However, these techniques
require trained staff and expensive equipment, and are time-consuming.
Moreover, the detection of such low-abundance biomarkers in biological
fluids (e.g. blood, urine, saliva) requires large quantities of the sample
and complicated sample preparation. Consequently, these label-based
techniques encounter problems of cost-effectiveness and throughput under