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BACKGROUND: The Basic Public Health Service (BPHS), a recently announced free healthcare program, aims to combat the most prevalent Noncommunicable Disease-"Hypertension" (HTN)-and its risk factors on a nationwide scale. In China, there is a rife that HTN less impacts women during their lifetime. We, therefore, aimed to evaluate the sex disparity in hypertension patients with comorbidities among south-west Chinese and the contribution of BPHS to address that concern. METHODS: We have opted for a multistage stratified random sampling method to enroll hypertensive patients of 35 years and older, divided them into BPHS and non-BPHS groups. We assessed the sex disparity in HTN patients with four major comorbidities- Dyslipidemia, Diabetes Mellitus (DM), Cardiovascular Disease (CVD), and Chronic Kidney Disease (CKD), and descriptive data were compiled. Odds ratios from logistic regression models estimated the effectiveness of BPHS in the management of HTN with comorbidities. RESULTS: Among 1521 hypertensive patients,1011(66.5%) were managed in the BPHS group. The proportion of patients who had at least one comorbidity was 70.7% (95% confidence interval [CI]: 66.3-76.8%), patients aged 65 years and older were more likely to have coexisting comorbidities. Participants who received the BPHS showed significant blood pressure (BP) control with two comorbidities (odds ratio [OR] = 2.414, 95% CI: 1.276-4.570), three or more (OR = 5.500, 95%CI: 1.174-25.756). Patients with dyslipidemia and DM also benefited from BPHS in controlling BP (OR = 2.169, 95% CI: 1.430-3.289) and (OR = 2.785, 95%CI: 1.242-6.246), respectively. In certain high-income urban survey centers, there was sex differences in the HTN management provided by BPHS, with men having better BP control rates than women. CONCLUSIONS: Perhaps this is the first study in China to succinctly show the effectiveness and sex disparity regarding "management of hypertensive comorbidities". This supports that the BPHS program plays a pivotal role in controlling BP, therefore should recommend the national healthcare system to give women a foremost priority in BPHS, especially to those from low-socioeconomic and low-scientific literacy regions.
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Diabetes Mellitus , Dislipidemias , Hipertensão , Humanos , Feminino , Masculino , Pressão Sanguínea , China/epidemiologia , Comorbidade , Hipertensão/epidemiologia , Diabetes Mellitus/epidemiologia , Fatores de Risco , Serviços de SaúdeRESUMO
The increasing deployment of industrial robots in manufacturing requires accurate fault diagnosis. Online monitoring data typically consist of a large volume of unlabeled data and a small quantity of labeled data. Conventional intelligent diagnosis methods heavily rely on supervised learning with abundant labeled data. To address this issue, this paper presents a semi-supervised Informer algorithm for fault diagnosis modeling, leveraging the Informer model's long- and short-term memory capabilities and the benefits of semi-supervised learning to handle the diagnosis of a small amount of labeled data alongside a substantial amount of unlabeled data. An experimental study is conducted using real-world industrial robot monitoring data to assess the proposed algorithm's effectiveness, demonstrating its ability to deliver accurate fault diagnosis despite limited labeled samples.
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Water is a basic resource and an essential component of living organisms. It often exhibits some novel properties under confinement. The water clusters (H2O)n (n = 4-8) confined in the cavity of uranyl peroxide cluster Na20(UO2)20(O2)30 (U20) have been computationally investigated by using ab initio molecular dynamics (AIMD) simulations and density functional theory (DFT) calculations in this study. The results show that the confined water clusters can form hydrogen bonds with the internal oxygen atoms (Ouranyl) of U20, and their conformations changed significantly. The average lengths (2.553-2.645 Å) of hydrogen bonds in confined (H2O)n are shorter than those (2.731-2.841 Å) in the corresponding free water clusters. Moreover, these confined hydrogen bonds show better hydrogen bond patterns according to the quantified indices. The natural bond orbital (NBO) calculations determine that there is electron transferring from the U20 to its interior (H2O)n. It is the main reason for enhancing hydrogen bond interactions among the confined water molecules because their oxygen atoms are more negatively charged and their hydrogen atoms are more positively charged. The quantum theory of atoms in molecules (QTAIM) and interacting quantum atoms (IQA) analyses indicate that the confined hydrogen bonds are more covalent, based on the significant electron density ρ(r) and local energy density H(r) at the bond critical points (BCPs), and the stronger energies of interatomic exchange interactions (Vxc). These findings may help to promote the communication of confined water clusters and enrich the understating of confined hydrogen bonds.
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Coarse-graining (CG) molecular dynamics (MD) simulations are widely used in interpreting experimental observations and predicting assembly morphology as well as collective behaviour but also face the problem of poor accuracy. A main issue is that cross-termed interactions between different CG beads are inadequately parameterized. This work proposes a novel top-down and bottom-up combined strategy to parameterize both self- and cross-termed interactions of zwitterionic phospholipids in water solution based on a piecewise Morse potential describing nonbonded van der Waals interactions. The self-interacting force parameters were optimized by matching experimental density, heat vapourization, and surface tension in a top-down manner, while the cross-termed interactions were optimized by fitting pseudo properties obtained from atomistic simulations in a bottom-up way, including mixing density, intermolecular energy, and radial mixing coefficient. The transferability of the CG force field (FF) was confirmed by reproducing a variety of structural and thermodynamic properties of lipid membranes in both liquid and gel phases. This FF can well depict vesicle self-assembly and vesicle fusion processes. Matching pseudo properties opens a new way to develop CG FF with increased accuracy and transferability.
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Triglycerides (TGs) play important roles in renewable energies, food production, medicine, and metabolism in organisms. Here, we developed a novel coarse-grained (CG) force field (FF) for triglycerides to reproduce both the structural and thermodynamic properties of bulk TGs, TG/air interfaces, and TG/water mixtures using molecular dynamics (MD) simulations. We rigorously optimized the bonded and nonbonded force parameters between the CG beads of TGs and nonbonded force parameters between TG beads and polarizable CG water beads by employing an efficient meta-multilinear interpolation parameterization algorithm recently developed by us. This CG FF performs very well in reproducing the percolating network of the TG bulk phase self-assembled in water and a variety of molecular conformations predicted by all-atom MD simulations. More importantly, it also correctly reproduces multiple experimentally measurable macroscopic thermodynamic properties, including the density and surface tensions of both the TG/air and TG/water interfaces. This paves the way for studying more complicated systems involving TGs on a large scale.
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BACKGROUND: Congenital heart disease (CHD) is the leading cause of mortality in childhood worldwide. However, a large number of children with CHD are not diagnosed promptly in low- and middle-income regions, due to limited healthcare resources and lack the ability of prenatal and postnatal ultrasound examinations. The research on asymptomatic CHD in the community is still blank, resulting in a large number of children with asymptomatic CHD can not be found and treated in time. Through the China-Cambodia collaborative health care initiative, the project team conducted research, screened children's CHD through a sampling survey in China and Cambodia, collected relevant data, and retrospectively analyzed the data of all eligible patients. OBJECTIVES: The project aimed to evaluate the prevalence of asymptomatic CHD in a sample population of 3-18years old and effects on their growth status and treatment outcomes. METHODS: We examined the prevalence of 'asymptomatic CHD' among 3-18years old children and adolescents at the township/county levels in the two participating. A total of eight provinces in China and five provinces in Cambodia were analyzed from 2017 to 2020. During 1 year follow-up after treatment, the differences in heights and weights of the treated and control groups were evaluated. RESULTS: Among the 3,068,075 participants screened from 2017 to 2020, 3967 patients with asymptomatic CHD requiring treatment were identified [0.130%, 95% confidence interval (CI) 0.126 -0.134%]. The prevalence rate of CHD ranged from 0.02 to 0.88%, and was negatively related to local per capita GDP (p = 0.028). The average height of 3310 treated CHD patients were 2.23% (95% CI: -2.51%~-1.9%) lower than that of the standard group and the average weight was - 6.41% (95% CI: -7.17%~-5.65%) lower, the developmental gap widening with advancing age. One year after treatment, the relative height difference remained comparable while that, in weight was reduced by 5.68% (95% CI: 4.27% ~7.09%). CONCLUSIONS: Asymptomatic CHD now is often overlooked and is an emerging public health challenge. Early detection and treatment are essential to lower the potential burden of heart diseases in children and adolescents.
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Amigos , Cardiopatias Congênitas , Criança , Feminino , Adolescente , Gravidez , Humanos , Camboja , Estudos Retrospectivos , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias Congênitas/epidemiologia , China/epidemiologia , Diagnóstico PrecoceRESUMO
Charge-shift (CS) bonding is a new bonding paradigm in the field of chemical bonds. Our recent study has revealed that certain Cu/Ag/Au-bonds display both CS bonding and ω-bonding characters. In this investigation, we extend our study to halogen bonding. Our focus is on scrutinizing the CS bonding in halogen-bonded BXY (B is a small Lewis base H2O or NH3; X and Y are halogen atoms) complexes by using natural bond orbital (NBO) analysis, natural resonance theory (NRT), and atoms in molecules (AIM) methods. The primary objective is to establish a connection between halogen bonding (B-X) in BXY and CS bonding in free XY (di-halogens). The calculations indicate that the studied BXY can be classified into two types. One type with a weak halogen bond shows closed-shell interaction. The other type with a stronger B-X interaction exhibits both CS bonding and ω-bonding characters (as seen in NH3ClF, NH3BrF, and NH3IF). Another interesting finding is a novel propensity that the CS bonding in free XY tends to carry over the halogen bonding in BXY, and the same propensity is found in Cu/Ag/Au ω-bonded species. The present study may offer an approach to probe CS bonding in many more 3c/4e ω-bonded molecules.
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A series of unnatural tripeptides, each consisting of two aromatic γ-amino acid residues and an Ï-amino acid residue, are designed to probe their folding into hairpin conformations. The Ï-amino acid residues, with aliphatic or aromatic spacers of different sizes, serve as the loop of the hairpins. Studies based on one-dimensional (1D) 1H NMR performed at different concentrations, solvent polarity, and temperature, along with 2D-NMR studies, demonstrated that the doubly H-bonded aromatic γ-amino acid residues play important roles in driving these tripeptides into the hairpin conformation. The loop based on 5-aminovaleric acid, which offers a four-carbon (CH2)4 spacer, enhanced the stability of the corresponding hairpin, while loops having a shorter, a longer and a more rigid spacer disfavored the formation of the hairpins. Results from computational studies are in good agreement with the experimental observations. Furthermore, the crystal structure of peptide 1b revealed the expected hairpin conformation in the solid state. This turn motif, which contains H-bonded aromatic γ-amino acid residues as the core unit and an Ï-amino acid residue serving as the loop, provides a new platform that can be used to obtain a variety of turn conformations by incorporating diverse amino acids into the loops.
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Coarse-grained (CG) molecular dynamics simulations are widely used to predict morphological structures and interpret mechanisms of mesoscopic behavior between the scope of traditional experiments and all-atom simulations. However, most current CG force fields (FFs) are not precise enough, especially for polar molecules or functional groups. A main obstacle in developing accurate CG FFs for polar molecules is the freezing problem met at room temperature. In this work, we introduce an indirect parametrization strategy for weakly polar groups by considering their short-chain homologs to avoid freezing. Here, a polar group containing three to four heavy atoms is mapped into one CG bead that is connected to one alkyl bead composed of three or four carbons. The CG beads interact via 4-parameter nonbonded Morse potentials and harmonic bonded potentials. An efficient meta-multilinear interpolation parameterization algorithm, as recently developed by us, is used to rigorously optimize the force parameters. Satisfactory accuracy is witnessed in terms of the density, heat of vaporization, surface tension, and solvation free energy of the homologs of twelve polar molecules, all deviating from the experiment by less than 5%. The transferability of the current FF is indicated by the predicted density, heat of vaporization, and end-to-end distance distributions of fatty acid methyl esters composed of multiple functional groups parameterized in this work.
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Coarse-grained (CG) molecular dynamics are powerful tools to access a mesoscopic phenomenon and simultaneously record microscopic details, but currently the CG force fields (FFs) are still limited by low parameterization efficiency and poor accuracy especially for polar molecules. In this work, we developed a Meta-Multilinear Interpolation Parameterization (Meta-MIP) algorithm to optimize the CG FFs for alcohols. This algorithm significantly boosts parameterization efficiency by constructing on-the-fly local databases to cover the global optimal parameterization path. In specific, an alcohol molecule is mapped to a heterologous model composed of an OH bead and a hydrocarbon portion which consists of alkane beads representing two to four carbon atoms. Non-bonded potentials are described by soft Morse functions that have no tail-corrections but can still retain good continuities at truncation distance. Nearly all of the properties in terms of density, heat of vaporization, surface tension, and solvation free energy for alcohols predicted by the current FFs deviate from experimental values by less than 7%. This Meta-MIP algorithm can be readily applied to force field development for a wide variety of molecules or functional groups, in many situations including but not limited to CG FFs.
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A fast, reasonable, and transferable coarse-grained (CG) molecular dynamics force field (FF) is essential to combine experimental and simulation data. However, the parameterization of CG FF usually requires massive computation, which hinders its rapid development. Here, we presented an efficient optimization protocol by combining multilinear interpolation technique with simplex algorithm. In this preliminary work, taking the experimental properties as the benchmark, we constructed a new set of CG FF for water and n-alkanes by adopting piecewise Morse function to describe the nonbonded interactions. This CG FF has a delicate balance between efficiency, accuracy, and transferability and well reproduced the correct structural and thermodynamics properties of pure water and alkane liquids. More importantly, optimized Morse potential was also successfully applied to describe the interactions between water and n-alkanes. It nicely predicted the phase separation, interface tension, hydration free energy, and formation of microemulsions of water/oil mixtures. © 2019 Wiley Periodicals, Inc.
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BACKGROUND: The noninvasive assessment of hepatic inflammatory activity (HIA) is crucial for making clinical decisions and monitoring therapeutic efficacy in chronic liver disease (CLD). PURPOSE: To develop MRI-based radiomics models by extracting features from the whole liver and localized regions of the right liver lobe, compare the efficiency of two radiomics models, and further develop a radiomics nomogram for the assessment of HIA in CLD. STUDY TYPE: Retrospective. POPULATION: In all, 137 consecutive patients. FIELD STRENGTH/SEQUENCE: 1.5T/T2 -weighted imaging. ASSESSMENT: All patients (nonsignificant HIA, n = 98; significant HIA, n = 39) were randomly divided into a training (n = 95) and a test cohort (n = 42). Radiomics features were extracted from the regions covering the whole liver (ROI-w) and localized regions of the right liver lobe (ROI-r). Least absolute shrinkage and selection operator (LASSO) and multivariate logistic regression analyses were used to select features and develop radiomics models. A combined model fusing the valuable radiomics features with clinical-radiological predictors was developed. Finally, a radiomics nomogram derived from the combined model was developed. STATISTICAL TESTS: Synthetic minority oversampling technique algorithm, LASSO, receiver operator characteristic curve, and calibration curve analysis were performed. RESULTS: The area under the curve (AUC), sensitivity, and specificity of the ROI-w radiomics model in assessing HIA were 0.858, 0.800, and 0.733, respectively. The ROI-r model were 0.844, 0.733, and 0.867, respectively. No differences were detected between the two radiomics models (P = 0.8329). The combined model fusing valuable ROI-w radiomics features, albumin, and periportal edema exhibited a promising performance (AUC, 0.911). The calibration curves showed good agreement between the actual observations and nomogram predictions. DATA CONCLUSION: The MRI-based radiomics models had a powerful ability to evaluate HIA and the ROI-w radiomics model was comparable to the ROI-r model. Moreover, the radiomics nomogram could be a favorable method to individually estimate HIA in CLD. J. MAGN. RESON. IMAGING 2020;52:1668-1678.
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Hepatopatias , Imageamento por Ressonância Magnética , Humanos , Hepatopatias/diagnóstico por imagem , Nomogramas , Estudos RetrospectivosRESUMO
Many studies have been carried out on ultrasound computed tomography (USCT) for its potential application in breast imaging. The sound speed (SS) image modality in USCT can help doctors diagnose the breast cancer, as the tumor usually has a higher sound speed than normal tissues. Travel time is commonly used to reconstruct SS image. Raypath travel-time tomography (RTT) assumes that the sound wave travels through a raypath. RTT is computationally efficient but with low contrast to noise ratio (CNR). Fresnel zone travel-time tomography (FZTT) is based on the assumption that the sound wave travels through an area called the Fresnel zone. FZTT can provide SS image with high CNR but low accuracy due to the wide Fresnel zone. Here, we propose a zone-shrinking Fresnel zone travel-time tomography (ZSFZTT), where a weighting factor is adopted to shrink the Fresnel zone during the inversion process. Numerical phantom and in vivo breast experiments were performed with ZSFZTT, FZTT, and RTT. In the numerical experiment, the reconstruction biases of size by ZSFZTT, FZTT, and RTT were 0.2%~8.3%, 2.3%~31.7%, and 1.8%~25%; the reconstruction biases of relative SS value by ZSFZTT, FZTT, and RTT were 24.7%~42%, 53%~60.8%, and 30.3%~47.8%; and the CNR by ZSFZTT, FZTT, and RTT were 67.7~96.6, 68.5~98, and 1.7~2.7. In the in vivo breast experiment, ZSFZTT provided the highest CNR of 8.6 compared to 8.1 by FZTT and 1.9 by RTT. ZSFZTT improved the reconstruction accuracy of size and the relative reconstruction accuracy of SS value compared to FZTT and RTT while maintaining a high CNR similar to that of FZTT.
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Algoritmos , Doenças Mamárias , Ultrassonografia Mamária , Doenças Mamárias/diagnóstico por imagem , Feminino , Humanos , Imagens de Fantasmas , Som , Tomografia , Tomografia Computadorizada por Raios XRESUMO
Optical microscopy shows that the peripheral antimicrobial peptide (AMP) gomesin does not disrupt the bacterial membrane by forming stable transmembrane pores but induces lipid accumulation domains, which is followed by a sudden burst near the domains. The molecular action mechanisms of gomesin on vesicle and planar bilayer membranes are investigated in this work using coarse-grained molecular dynamics simulations. By comparing the membrane morphology and property changes induced by gomesin and the pore-forming AMP melittin, we determined that the amphiphilic shape of the AMPs is a key factor affecting the mechanism of cell death. The binding of wedge-shaped gomesin, with a small hydrophobic surface, onto the membrane induces protrusion and folding of the outer monolayer followed by sudden membrane lacerations at the axillae of the protuberances. Alternatively, cylinder-shaped melittins with comparable hydrophilic and hydrophobic surfaces destroy membranes by forming stable pores coexisting with exocytosis-like buddings and endocytosis-like invaginations. The multiple actions of AMPs on the bacterial membrane suggest diverse paradigms for designing molecular carriers for delivering drugs to the cell.
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Antibacterianos/química , Peptídeos Catiônicos Antimicrobianos/química , Bicamadas Lipídicas/metabolismo , Lipossomos/metabolismo , Bicamadas Lipídicas/química , Lipossomos/química , Meliteno/química , Microdomínios da Membrana/efeitos dos fármacos , Simulação de Dinâmica MolecularRESUMO
The noble-gas hydrides, HNgX (X is an electronegative atom or fragment), represent potential high-energy materials because their two-body decomposition process, HNgX â Ng + HX, is strongly exoergic. Our previous studies have shown that each member of the HNgX (X = halogen atom or CN/NC fragment) molecules is composed of three leading resonance structures: two ω-bonding structures (H-Ng+ :X- and H:- Ng+-X) and one long-bonding structure (Hâ§X). The last one paints a novel [small sigma, Greek, circumflex]-type long-bonding picture. The present study focuses on the relationship between this novel bonding motif and the unusual energetic properties. We chose HNgCO+/CS+/OSi+/CN/NC, with the formula HNgAB (Ng = He, Ar, Kr, Xe, Rn; AB = CO+/CS+/OSi+/CN/NC) as the research system. We first investigated the bonding of HNgCO+ and its analogous HNgCS+/OSi+ species using NBO/NRT methods, and quantitatively compared the bonding with that in HNgCN/NC molecules. NBO/NRT results showed that each of the HNgCO+/CS+/OSi+ molecules could be better represented as a resonance hybrid of ω-bonding and long-bonding structures, but the long-bonding is much weaker than that in HNgCN/NC molecules. Furthermore, we introduced the long-bonding concept into the rationalization of the high-energy properties, and found a good correlation between the highly exothermic two-body dissociation channel and the long-bond order, bH-A. We also found that the long-bond order is highly tunable for these noble-gas hydrides due to its dependence on the nature of the electronegative AB fragments or the central noble-gas atoms, Ng. On the basis of these results, we could optimize the energetic properties by changing the long-bonding motif of our studied molecules. Overall, this study shows that the long-bonding model provides an easy way to rationalize and modulate the unusual energy properties of noble-gas hydrides, and that it is helpful to predict some noble-gas hydrides as potential energetic materials.
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A 2 × 2 factorial arrangement (rearing room with or without pad-fan cooling × diet with or without 2.5 kg/t organic acid) was used to evaluate the effect of pad-fan cooling and dietary organic acid supplementation during perinatal period on reproductive performance and antioxidant status of sows in hot weather. This study was conducted in a subtropical city in Guangdong Province in South China between August and October, 2015. At day 85 of gestation, a total of 112 sows were randomly assigned to the four treatments with 28 sows per treatment, and maintained until day 21 of lactation, and the feeding trial lasted for 51 days. During the experimental period, room temperature and humidity were recorded hourly. The lactation feed intake of sows (P = 0.109) and stillbirths (P < 0.05) increased when the sows were reared in the room with the pad-fan cooling against the room without pad-fan cooling. The number of weak newborns per litter and the malondialdehyde content in days 14 and 21 milk decreased (P < 0.05), while the lactation feed intake of sows, weaned litter weights, and individual pig weights increased when the sows were fed the organic acid (P < 0.05). In conclusion, pad-fan cooling in rearing room improved the lactation feed intake of sows, and dietary organic acid supplementation improved reproductive performance and milk antioxidant status of sows. Pad-fan cooling is recommended in farrowing room, but not in gestating room.
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Ração Animal/análise , Antioxidantes/química , Dieta/veterinária , Temperatura Alta , Lactação/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Ácidos/uso terapêutico , Fenômenos Fisiológicos da Nutrição Animal , Animais , China , Suplementos Nutricionais , Feminino , Malondialdeído/química , Leite , Paridade , Gravidez , Suínos , Desmame , Tempo (Meteorologia)RESUMO
The intercalation behaviour of cobalt underneath both epitaxial graphene monolayer and bilayer on 6H-SiC(0001) have been investigated by scanning tunneling microscopy (STM) and density functional theory (DFT). Upon deposition, cobalt atoms prefer to agglomerate into clusters on the epitaxial graphene. After annealing the sample to 850 °C, the intercalation of the adsorbed cobalt atoms into both monolayer and bilayer epitaxial graphene on SiC takes place, as observed by the atomically resolved STM images. Further studies based on DFT modeling and simulated STM images show that, resulting from the interplay between the intercalated cobalt atoms and the carbon layers sandwiching it, the most energetically favourable intercalation sites of cobalt atoms underneath monolayer and bilayer graphene differ. Furthermore, the results show energy barriers of 0.60 eV and 0.41 eV for cobalt penetration through mono-vacancy defects at monolayer and bilayer graphene.
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Two experiments were conducted to investigate the effect of combined supplementation of α-galactosidase and xylanase on nutrient digestibility and growth performance in growing pigs. Experiment 1 had a 2 × 2 Latin square design, where eight barrows (45.0 ± 0.52 kg body weight [BW]) were fitted with a simple T-cannula in the distal ileum and received a basal diet without or with supplementation of α-galactosidase (12 U/kg diet) and xylanase (15 AXC/kg diet) within two periods of 10 d. The apparent ileal digestibility (AID) and apparent total tract digestibility of nutrients, pH, viscosity of digesta and digestive enzyme activities were assessed. In Experiment 2, a total of 432 growing pigs (initial BW 44.7 ± 0.66 kg) were allocated to four treatments. Diets were based on corn and soybean meal and had a normal or reduced nutrient level (reduced by 0.42 kJ digestible energy [DE] per kg and 0.8% crude protein). Both diets were offered without or with supplementation of α-galactosidase and xylanase. The growth performance was assessed within a 43-d feeding period, where at the end, biochemical serum indices were estimated. In Experiment 1, the enzyme-supplemented diet had a greater contents of DE and DE/gross energy ratio (p < 0.05), and a higher AID of Arg, raffinose, stachyose and arabinoxylan (p < 0.05). In Experiment 2, the low nutrient level caused lower daily gain (p < 0.05), which was partially compensated by enzyme addition. Enzyme addition also increased the serum concentration of Lys (p < 0.05). Moreover, it appears that the tested enzyme supplementation could increase dietary DE, serum total amino acid concentrations and decrease serum urea nitrogen.
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Dieta/veterinária , Digestão/efeitos dos fármacos , Endo-1,4-beta-Xilanases/metabolismo , Sus scrofa/fisiologia , alfa-Galactosidase/metabolismo , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Suplementos Nutricionais/análise , Endo-1,4-beta-Xilanases/administração & dosagem , Feminino , Masculino , Glycine max/química , Sus scrofa/crescimento & desenvolvimento , Zea mays/química , alfa-Galactosidase/administração & dosagemRESUMO
Investigations on the bottom-up fabrication of graphene nanostructures with 10, 10'-dibromo-9, 9'-bianthryl (DBBA) as a precursor on Ru(1010) were carried out using scanning tunnelling microscopy (STM) and density functional theory (DFT) calculations. Upon annealing the sample at submonolayer DBBA coverage, N = 7 graphene nanoribbons (GNRs) aligned along the [1210] direction form. Higher DBBA coverage and higher annealing temperature lead to the merging of GNRs into ribbon-like graphene nanoflakes with multiple orientations. These nanoflakes show different Moiré patterns, and their structures were determined by DFT simulations. The results showed that GNRs possess growth preference on the Ru(1010) substrate with a rectangular unit cell, and GNRs with armchair and zigzag boundaries are obtainable. Further DFT calculations suggest that the interaction between graphene and the substrate controls the orientations of the graphene overlayer and the growth of graphene on Ru(1010).
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A bottom-up fabrication of graphene via molecular self-assembly of p-Terphenyl on Ru(0001) has been investigated by scanning tunneling microcopy and density functional theory. Upon annealing of the sample at 450 °C, the intermediate stage is observed, in which the adsorbed p-Terphenyl molecules and graphitized flakes converted from the molecules coexist, implying the onset of dehydrogenation of p-Terphenyl. At the annealing temperature of 480 °C, the graphitized flakes start to convert into graphene. An adsoption energy of 5.99 eV is calculated for an individual p-Terphenyl molecule on Ru(0001), denoting a strong interaction between the adsorbate and substrate. The intermolecular interaction brings an extra adsorption energy of 0.28 eV for each molecule in the di-molecule adsorption system. During the conversion process from adsorbed molecule into graphene, the intermolecular interaction leads to the increase of the dehydrogenation barrier from 1.52 to 1.64 eV.