The current outbreak of coronavirus disease-2019 (COVID-19) poses unprecedented challenges to global health
. The new coronavirus responsible for this outbreak-severe acute respiratory syndrome ...coronavirus 2 (SARS-CoV-2)-shares high sequence identity to SARS-CoV and a bat coronavirus, RaTG13
. Although bats may be the reservoir host for a variety of coronaviruses
, it remains unknown whether SARS-CoV-2 has additional host species. Here we show that a coronavirus, which we name pangolin-CoV, isolated from a Malayan pangolin has 100%, 98.6%, 97.8% and 90.7% amino acid identity with SARS-CoV-2 in the E, M, N and S proteins, respectively. In particular, the receptor-binding domain of the S protein of pangolin-CoV is almost identical to that of SARS-CoV-2, with one difference in a noncritical amino acid. Our comparative genomic analysis suggests that SARS-CoV-2 may have originated in the recombination of a virus similar to pangolin-CoV with one similar to RaTG13. Pangolin-CoV was detected in 17 out of the 25 Malayan pangolins that we analysed. Infected pangolins showed clinical signs and histological changes, and circulating antibodies against pangolin-CoV reacted with the S protein of SARS-CoV-2. The isolation of a coronavirus from pangolins that is closely related to SARS-CoV-2 suggests that these animals have the potential to act as an intermediate host of SARS-CoV-2. This newly identified coronavirus from pangolins-the most-trafficked mammal in the illegal wildlife trade-could represent a future threat to public health if wildlife trade is not effectively controlled.
Under investigation in this paper is the AB system, which describes marginally unstable baroclinic wave packets in geophysical fluids. Through symbolic computation, Lax pair and conservation laws are ...derived and the Darboux transformation is constructed for this system. Furthermore, three types of breathers on the continuous wave (cw) background are generated via the obtained Darboux transformation. The following contents are mainly discussed by figures plotted: (1) Modulation instability processes of the Akhmediev breathers in the presence of small perturbations; (2) Propagations characteristics of Ma solitons; (3) Dynamic features of the breathers evolving periodically along the straight line with a certain angle of
z
-axis and
t
-axis.
One important goal of the current electrocatalysis is to develop integrated electrodes from the atomic level design to multilevel structural engineering in simple ways and low prices. Here, a series ...of oxygen micro‐alloyed high‐entropy alloys (O‐HEAs) is developed via a metallurgy approach. A (CrFeCoNi)97O3 bulk O‐HEA shows exceptional electrocatalytic performance for the oxygen evolution reaction (OER), reaching an overpotential as low as 196 mV and a Tafel slope of 29 mV dec−1, and with stability longer than 120 h in 1 m KOH solution at a current density of 10 mA cm−2. It is shown that the enhanced OER performance can be attributed to the formation of island‐like Cr2O3 microdomains, the leaching of Cr3+ ions, and structural amorphization at the interfaces of the domains. These findings offer a technological‐orientated strategy to integrated electrodes.
A new class of bulk electrodes is designed by incorporating oxide microdomains into the so‐called high‐entropy alloys (HEAs). From these, unprecedented oxygen evolution reaction (OER) activity is achieved, with an ultralow overpotential of 196 mV and a Tafel slope of 29 mV dec−1, and with stability longer than 120 h in 1 m KOH solution at current density of 10 mA cm−2.
In this paper, an inhomogeneous discrete nonlinear Schrödinger equation is analytically investigated. The modulation instability condition and conservation laws are derived. By virtue of the discrete ...Darboux transformation, two types of explicit solutions on the vanishing and non-vanishing backgrounds are generated. Those results might be useful in the study of solitons propagation in discrete optical fibers.
Dihydromyricetin (DMY), one of the flavonoids in vine tea, exerts several pharmacological actions. However, it is not clear whether DMY has a protective effect on pressure overload-induced myocardial ...hypertrophy. In the present study, male C57BL/6 mice aging 8⁻10 weeks were subjected to transverse aortic constriction (TAC) surgery after 2 weeks of DMY (250 mg/kg/day) intragastric administration. DMY was given for another 2 weeks after surgery. Blood pressure, myocardial structure, cardiomyocyte cross-sectional area, cardiac function, and cardiac index were observed. The level of oxidative stress in the myocardium was assessed with dihydroethidium staining. Our results showed that DMY had no significant effect on the blood pressure. DMY decreased inter ventricular septum and left ventricular posterior wall thickness, relative wall thickness, cardiomyocyte cross-sectional areas, as well as cardiac index after TAC. DMY pretreatment also significantly reduced arterial natriuretic peptide (ANP), brain natriuretic peptide (BNP) mRNA and protein expressions, decreased reactive oxygen species production and malondialdehyde (MDA) level, while increased total antioxidant capacity (T-AOC), activity of superoxide dismutase (SOD), expression of sirtuin 3 (SIRT3), forkhead-box-protein 3a (FOXO3a) and SOD2, and SIRT3 activity in the myocardium of mice after TAC. Taken together, DMY ameliorated TAC induced myocardial hypertrophy in mice related to oxidative stress inhibition and SIRT3 pathway enhancement.
Molecular dynamics was employed to study the inhibition mechanism of vinyl lactam‐based kinetic hydrate inhibitors (KHIs). By comparing the inhibition functions of the same KHIs at different initial ...locations, we found that the KHI molecules on the surface of hydrate nuclei could obviously prolong the hydrate induction time and exhibited the best inhibition effect. The impacts of KHIs on the methane migration and the arrangement of H2O molecules were analyzed at the molecular level. A gas‐adsorbing mechanism for KHIs (i.e., the KHIs with an excellent gas adsorption ability could reduce the supersaturation of methane in the aqueous solution, reinforce the migration resistance of methane to the nucleus, and further inhibit the hydrate growth) was proposed. In addition, the conformations of KHI polymer molecules in the aqueous solution are closely related to their inhibitory effect, that is, stretched skeletons and well‐organized structures would maximize their inhibitory effect.
Via the finite-gap integration theory, we study the defocusing Lakshmanan–Porsezian–Daniel (LPD) equation. Meanwhile, we derive the degenerate forms for the single-phase periodic solution. In ...addition, we obtain the basic and combined structures of the dispersive shock wave through the Whitham modulation equation parameterized by the Riemann invariant.
Abstract
Three-legged bosonic/fermionic magnetic ladder, reproducing the main features of magnetic lattice systems, is an ideal model to study the edge-bulk coupling and chiral edge dynamics, which ...are a hallmark of quantum Hall physics. Here, the ground state transition, localization, and chiral edge (bulk) states of an interacting three-legged bosonic magnetic ladder are studied analytically and numerically. When the system is in a quasi-steady state, using variational analysis, the threshold for the transition from zero momentum state to plane wave state is obtained. The energy spectrum, the ground state diagram, the chiral current of the system are presented, and the chiral current reversal at the state transition point is observed. Furthermore, the localization and its stability in the system are discussed, and rich localized phenomena (diffusion, breather, soliton, and self-trapping) are predicted. Stable soliton/breather prefers to form an edge state, while the self-trapping is favorite to form a bulk state, i.e. localized edge and bulk states are obtained. Particularly, for the unstable soliton in the ground state or metastable state, different kinds of chiral edge/bulk state and edge-bulk coupling are observed. The stability of the localized states, the edge-bulk coupling characteristics, and the chirality of the system depend on the energy band structure of the system. Additionally, a controllable transition between localized edge state and bulk state is realized by quenching the soliton state. We proposed a theoretical evidence to design and manipulate edge-bulk coupling and different kinds of localized/chiral edge (bulk) states in three-legged bosonic magnetic ladder.
Aims
To evaluate the compliance of patients after gastrectomy in taking oral nutritional supplementation and to explore the promoting and hindering factors.
Design
A mixed‐methods design with an ...explanatory sequential approach was employed.
Methods
We conducted a 12‐week longitudinal study to evaluate the oral nutritional supplementation compliance of 122 patients after gastric cancer surgery and the factors that affected their compliance. After the quantitative phase, we selected the interview subjects and developed the interview outline based on the analysis of the quantitative results. In‐depth interviews (n = 15) were conducted to explain and supplement the quantitative phase results. Data were collected from October 2019 to May 2020.
Results
The average overall compliance rate of oral nutritional supplementation in patients with gastric cancer over 12 weeks was 30.59%. Adverse reactions to oral nutritional supplementation, the identity of the main caregivers and the patient's financial ability were independent factors that affected patient compliance. In subsequent interviews, we extracted four themes: social support plays an important role in patients taking oral nutritional supplementation, adverse reactions discourage patients from continuing to take oral nutritional supplementation, patients' attitudes affect their motivation to take oral nutritional supplementation, and the different needs of patients for oral nutritional supplementation affect patient compliance.
Conclusion
Patients' compliance with oral nutritional supplementation after gastric cancer surgery is very low. Health education should pay more attention to the management of adverse reactions and the role of patients' peers and family members. Oral nutritional supplementation products should be diversified to provide patients with more choices.
Impact
This study clarifies the factors that hinder and promote oral nutritional supplementation compliance and provides an important reference for the establishment and revision of health education strategies for patients after gastric cancer surgery.
Background It is very necessary to implement gastric cancer screening in China to reduce the mortality of gastric cancer, but there are no national screening guidelines and programs. Understanding of ...individual preferences is conducive to formulating more acceptable screening strategies, and discrete choice experiments can quantify individual preferences. In addition, the first-degree relatives of gastric cancer patients are at high risk for gastric cancer. Compared with those without a family history of gastric cancer, the risk of gastric cancer in first-degree relatives of gastric cancer patients is increased by 60%. Therefore, a discrete choice experiment was carried out to quantitatively analyse the preferences of first-degree relatives of gastric cancer patients for gastric cancer screening to serve as a reference for the development of gastric cancer screening strategies. Methods A questionnaire was designed based on a discrete choice experiment, and 342 first-degree relatives of gastric cancer patients were investigated. In STATA 15.0 software, the data were statistically analysed using a mixed logit model. Results The five attributes included in our study had a significant influence on the preferences of first-degree relatives of gastric cancer patients for gastric cancer screening (P < 0.05). Participants most preferred the sensitivity of the screening program to be 95% (coefficient = 1.424, P < 0.01) with a willingness to pay 2501.902 Yuan (95% CI, 738.074-4265.729). In addition, the participants' sex and screening experiences affected their preferences. An increase in sensitivity 35 to 95% had the greatest impact on the participants' willingness to choose a gastric cancer screening program. Conclusion The formulation of gastric cancer screening strategies should be rooted in people's preferences. The influence of sex differences and screening experiences on the preferences of people undergoing screening should be considered, and screening strategies should be formulated according to local conditions to help them play a greater role. Keywords: Gastric cancer, Cancer screening, Discrete choice experiment, Preferences
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