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1.
J Phys Condens Matter ; 36(28)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38574683

RESUMO

In recent years, higher-order topological phases have attracted great interest in various fields of physics. These phases have protected boundary states at lower-dimensional boundaries than the conventional first-order topological phases due to the higher-order bulk-boundary correspondence. In this review, we summarize current research progress on higher-order topological phases in both crystalline and non-crystalline systems. We firstly introduce prototypical models of higher-order topological phases in crystals and their topological characterizations. We then discuss effects of quenched disorder on higher-order topology and demonstrate disorder-induced higher-order topological insulators. We also review the theoretical studies on higher-order topological insulators in amorphous systems without any crystalline symmetry and higher-order topological phases in non-periodic lattices including quasicrystals, hyperbolic lattices, and fractals, which have no crystalline counterparts. We conclude the review by a summary of experimental realizations of higher-order topological phases and discussions on potential directions for future study.

2.
Anal Biochem ; 689: 115502, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38453047

RESUMO

Myoglobin (Myo), creatine kinase-MB (CKMB), and cardiac troponin I (cTnI) are crucial biomarkers for diagnosing acute myocardial infarction (AMI) The accurate and rapid detection of these three targets can greatly improve the prognosis of AMI patients. Herein, this study developed a microfluidic immunofluorescence method that can detect all three targets in 10-15 min. Ultrasonic atomization and spray technology are used to modify the surface of the injection-molded microfluidic chip (MFC), which effectively solves the problem of biological cross-linking and antibody immobilization on the MFC surface. In addition, it improves the hydrophilicity of the chip surface, thus enhancing fluid self-driving effect. The linear response towards Myo, CKMB and cTnI range from 5 ng/mL to 500 ng/mL, 1 ng/mL to 70 ng/mL, and 0.05 ng/mL to 30 ng/mL, respectively. The intra-batch precision is ≤ 10%, and the inter-batch precision is ≤ 15%. Furthermore, this method shows good consistency compared with the BECKMAN ACCESS2 chemiluminescent immunoanalyzer. The present work provides an AMI diagnostic method with high sensitivity, good repeatability, high accuracy and simple operation, which can satisfy the needs of clinical diagnosis, and shows promising application prospects.


Assuntos
Microfluídica , Infarto do Miocárdio , Humanos , Infarto do Miocárdio/diagnóstico , Creatina Quinase Forma MB , Prognóstico , Troponina I , Biomarcadores , Mioglobina , Sensibilidade e Especificidade
3.
Food Chem ; 439: 138101, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38043286

RESUMO

In milk, fat exists in the form of milk fat globules (MFGs). The average size (average fat globules of different particle sizes) is the most common parameter when describing MFG size. There are different views on whether there is a correlation between MFG size and milk fat content. Is the MFG size correlated with milk fat content in ruminants? To address this question, we conducted two experiments. In experiment Ⅰ, dairy cows (n = 40) and dairy goats (n = 30) were each divided into a normal group and a low-fat group according to the milk fat content. In experiment Ⅱ, dairy cows (n = 16) and dairy goats (n = 12) were each divided into a normal group and a conjugated linoleic acid (CLA)-induced low-fat group. The normal groups were fed a basal diet, and the CLA-induced low-fat groups were fed the basal diet + 300 g/d CLA (cows) or the basal diet + 90 g/d CLA (goats). In both experiments, we determined the correlation between MFG size and milk composition and MFG distribution. The results showed that in the normal and low-fat groups of cows and goats, MFG size was not correlated with milk fat, protein, or lactose content or fat-to-protein ratio. Additionally, there was no difference in the distribution of large, medium, and small MFGs (P > 0.05). However, in the CLA-induced low-fat groups, we found a correlation between MFG size and milk fat content and fat-to-protein ratio (R2 > 0.3). Moreover, there was a significant change in the size distribution of MFGs. Therefore, in natural milk, MFG size was not correlated with milk fat content. Following CLA supplementation, MFG size was correlated with milk fat content. Our findings revealed that CLA and not milk fat affects MFG distribution and size.


Assuntos
Lactação , Ácidos Linoleicos Conjugados , Feminino , Bovinos , Animais , Ácidos Graxos/metabolismo , Leite/metabolismo , Dieta/veterinária , Cabras/metabolismo , Ácidos Linoleicos Conjugados/metabolismo , Suplementos Nutricionais
4.
J Dairy Sci ; 106(12): 9868-9878, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37678795

RESUMO

Rumen-protected choline (RPC) supplementation in the periparturient period has in some instances prevented and alleviated fatty liver disease in dairy cows. Mechanistically, however, it is unclear how choline prevents the accumulation of lipid droplets (LD) in liver cells. In this study, primary liver cells isolated from liver tissue obtained via puncture biopsy from 3 nonpregnant mid-lactation multiparous Holstein cows (∼160 d postpartum) were used. Analyses of LD via oil red O staining, protein abundance via Western blotting, and phospholipid content and composition measured by thin-layer chromatography and HPLC/mass spectrometry were performed in liver cells cultured in choline-deficient medium containing 150 µmol/L linoleic acid for 24 h. In a subsequent experiment, lipophagy was assessed in liver cells cultured with 30, 60, or 90 µmol/L choline-chloride. All data were analyzed statistically using SPSS 20.0 via t-tests or one-way ANOVA. Compared with liver cells cultured in Dulbecco's Modified Eagle Medium alone, choline deficiency increased the average diameter of LD (1.59 vs. 2.10 µm), decreased the proportion of small LD (<2 µm) from 75.3% to 56.6%, and increased the proportion of large LD (>4 µm) from 5.6% to 15.0%. In addition, the speed of LD fusion was enhanced by the absence of choline. Among phospholipid species, the phosphatidylcholine (PC) content of liver cells decreased by 34.5%. Seventeen species of PC (PC [18:2_22:6], PC [15:0_16:1], PC [14:0_20:4], and so on) and 6 species of lysophosphatidylcholine (LPC; LPC [15:0/0:0]), PC (22:2/0:0), LPC (20:2/0:0), and so on] were decreased, while PC (14:1_16:1) and LPC (0:0/20:1) were increased. Choline deficiency increased the triglyceride (TAG) content (0.57 vs. 0.39 µmol/mg) in liver cells and increased the protein abundance of sterol regulatory element binding protein 1, sterol regulatory element binding protein cleavage activation protein, and fatty acid synthase by 23.5%, 17%, and 36.1%, respectively. Upon re-supplementation with choline, the phenotype of LD (TAG content, size, proportion, and phospholipid profile) was reversed, and the ratio of autophagy marker LC3II/LC3I protein was significantly upregulated in a dose-dependent manner. Overall, at least in vitro in mid-lactation cows, these data demonstrated that PC synthesis is necessary for normal LD formation, and both rely on choline availability. According to the limitation of the source of liver cells used, further work should be conducted to ascertain that these effects are applicable to liver cells from postpartum cows, the physiological stage where the use of RPC has been implemented for the prevention and treatment of fatty liver.


Assuntos
Doenças dos Bovinos , Deficiência de Colina , Feminino , Bovinos , Animais , Deficiência de Colina/metabolismo , Deficiência de Colina/veterinária , Gotículas Lipídicas/metabolismo , Colina/farmacologia , Colina/metabolismo , Lactação/fisiologia , Fígado/metabolismo , Fosfolipídeos/análise , Suplementos Nutricionais/análise , Dieta/veterinária , Rúmen/metabolismo , Leite/química , Doenças dos Bovinos/metabolismo
5.
Sci Total Environ ; 895: 165139, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37379916

RESUMO

Short-wall block backfill mining can effectively control the movement of overlying strata, prevent water loss and utilize waste gangue materials. However, heavy metal ions (HMI) of gangue backfill materials in the mined-out area can be released and transported to the underlying aquifer, causing pollution of water resources in the mine. Accordingly, with short-wall block backfill mining technology, this study analyzed the sensitivity of gangue backfill materials to the environment. The pollution mechanism of gangue backfill materials to water resources was revealed, and the transport rules of HMI were explored. The regulation and control methods of water pollution in the mine were then concluded. The design method of backfill ratio for comprehensive protection of overlying and underlying aquifers was proposed. The results show that the release concentration of HMI, the gangue particle size, the floor lithology, the burial depth of the coal seam, and the depth of the floor fractures were the main factors that affected the transport behaviors of HMI. After long-term immersion, HMI of gangue backfill materials underwent hydrolysis and were released constantly. HMI were subjected to the coupled action of seepage, concentration, and stress and then driven by water head pressure and gravitational potential energy to transported downward along the pore and fracture channels in the floor with mine water as the carrier. Meanwhile, the transport distance of HMI increased with increasing release concentration of HMI, the permeability of the floor stratum, and the depth of floor fractures. Still, it decreased with increasing gangue particle size and the burial depth of the coal seam. On that basis, external-internal cooperative control methods were proposed to prevent the pollution of gangue backfill materials to mine water. Furthermore, the design method of the backfill ratio for comprehensive protection of overlying and underlying aquifers was proposed.

6.
Food Funct ; 14(5): 2304-2312, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36752527

RESUMO

In mammary epithelial cells, milk fat is synthesized as lipid droplets and secreted in the form of globules. Milk fat globules (MFGs) are covered by a lipid-protein membrane known as the milk fat globule membrane (MFGM). We randomly divided 12 Holstein cows into control and conjugated linoleic acid (CLA) groups. The control group was fed a basal diet, while the CLA group was fed the basal diet + CLA (15 g per kg DM) for 10 days. Cow performance, milk composition, and MFG size were measured daily. On day 10, we extracted MFGM proteins (n = 3) and identified them via quantitative proteomic analysis. We investigated the effects of the MFGM proteins from control and CLA-treated milk on the lipid droplet formation in MAC-T cells. Compared with the control group, the CLA group had reduced milk fat content (3.39 g/100 mL vs. 2.45 g/100 mL) and MFG size parameters (D[4,3] of 3.85 µm vs. 3.37 µm; D[3,2] of 3.24 µm vs. 2.83 µm). The specific surface area (SSA) increased in the CLA group. A total of 361 differentially expressed proteins were identified in the CLA group by iTRAQ quantitative proteomic analysis. Among these proteins, 100 were upregulated and 251 were downregulated (p < 0.05). In MAC-T cells, CLA-MFGM proteins increased the diameter of the lipid droplets to 1.32 µm. CLA-MFGM proteins decreased the proportion of the small lipid droplets (15.33% vs. 47.78%) and increased the proportion of the large lipid droplets (25.04% vs. 11.65%). CLA-MFGM proteins promoted lipid droplet fusion. Therefore, MFGM proteins play an important role in the regulation of the lipid droplet size.


Assuntos
Ácidos Linoleicos Conjugados , Gotículas Lipídicas , Feminino , Bovinos , Animais , Gotículas Lipídicas/metabolismo , Proteínas do Leite/metabolismo , Proteômica , Glicolipídeos/metabolismo , Células Epiteliais/metabolismo , Lactação , Ácidos Linoleicos Conjugados/farmacologia
7.
Sci Rep ; 12(1): 11783, 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35821389

RESUMO

Aiming at the problems that it is difficult to predict rock burst accurately in engineering practice and the implementation parameters of rock burst prevention measures depend on some empirical formulas, in order to study the advantages and disadvantages of different in-situ modification mechanisms deeply, determine the applicable conditions of unusual in-situ modification measures, and provide a theoretical basis for forming adaptive in-situ modification control schemes. Two kinds of modified control methods using the same foundation involve engineering scale and indoor scale. With the help of scale transformation, the whole failure process analysis test of bearing rock samples was carried out. The results show that various modification measures can effectively control the properties, and realize "hard-rock softening or soft-rock hardening" by changing the physical and mechanical parameters of the target rock sample. Compared with the control group, the automatic parameters of rocks deteriorated significantly under different modification measures. The evolution law of carrying energy is similar. However, there are obvious diversity between various modification measures in plastic stage and post-peaking phase stage, which provides favorable conditions for rock burst prevention. Based on this, an adaptive modification control system was constructed. At the same time, filling materials is considered to increase the energy of post-peaking phase (non newtonian fluid: energy-absorbing materials), and further slow down the intensity of released energy within post-peaking phase stage. Because rock burst is characterized by rapid release of energy, non newtonian fluid has a good absorption effect on high-speed impact force. Therefore, in the design test, the effect of non newtonian fluid is realized by applying a high loading rate, and the evaluation of energy absorption effect of bearing rock samples filled with non newtonian fluid in borehole is considered.

8.
Ecol Evol ; 12(5): e8927, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35592070

RESUMO

Density dependence in reproduction plays an important role in stabilizing population dynamics via immediate negative feedback from population density to reproductive output. Although previous studies have shown that negative density-dependent reproduction is associated with strong spacing behavior and social interaction between individuals, the proximal mechanism for generating negative density-dependent reproduction remains unclear. In this study, we investigated the effects of density-induced stress on reproduction in root voles. Enclosed founder populations were established by introducing 6 (low density) and 30 (high density) adults per sex into per enclosure (four enclosures per density in total) during the breeding season from April to July 2012 and from May to August 2015. Fecal corticosterone metabolite (FCM) levels, reproductive traits (recruitment rate and the proportion of reproductively active individuals), and founder population numbers were measured following repeated live trapping in both years. The number of founders was negatively associated with recruitment rates and the proportion of reproductively active individuals, displaying a negative density-dependent reproduction. FCM level was positively associated with the number of founders. The number of founder females directly affected the proportion of reproductive females, and directly and indirectly through their FCM levels affected the recruitment rate; the effect of the number of male founders on the proportion of reproductive males was mediated by their FCM level. Our results showed that density-induced stress negatively affected reproductive traits and that density-induced stress is one ecological factor generating negative density-dependent reproduction.

9.
Plant Signal Behav ; 17(1): 2005882, 2022 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-34913407

RESUMO

Seed germination and seedling development in nearly all orchid species rely on a symbiotic relationship with mycorrhizal fungi; however, this is not the case with all mycorrhizal fungi. This study aims to provide an understanding about the important role of mycorrhiza in seed germination and growth of Paphiopedilum barbigerum. Therefore, we isolated and identified endophytic fungi from the roots of wild P. barbigerum. The beneficial mycorrhizal fungi Epulorhiza sp. FQXY019 and Tulasnella calospora FQXY017 were screened by seed symbiotic germination tests and found to promote seed germination. However, only the seeds inoculated with FQXY019 progressed from the seed germination to rooting stage. This shows that mycorrhizal fungi and P. barbigerum have a specific relation at different growth phases. In addition, we selected FQXY019 and inoculated it into MS medium, B5 medium, OMA medium, and PDA medium. The results showed that FQXY019 co-cultured on PDA significantly promoted the increase in seedling fresh weight, leaf length, and root length (p < .01). Furthermore, it significantly promoted the root number and leaf number of seedlings compared with those co-cultured on MS, B5, and OMA media and control (p < .05). Thus, this study demonstrated the promoting effect of Epulorhiza sp. FQXY019 on seed germination and seedling development, making it an alternative method for the artificial propagation of P. barbigerum.


Assuntos
Micorrizas , Orchidaceae , Germinação , Orchidaceae/microbiologia , Plântula , Sementes , Simbiose
10.
Artigo em Inglês | MEDLINE | ID: mdl-34135982

RESUMO

BACKGROUND: Rho-related coiled helix forming protein kinase (Rho-ROCK) and another important fibrogenic factor-PDGF play a critical role in collagen deposition in rat lung tissue. Yifei decoction (YFT), a Chinese herbal decoction, has been used to treat idiopathic pulmonary fibrosis (IPF) in clinical practice and has produced positive outcomes; however, convincing evidence is currently lacking. The present study aimed to investigate the effects of YFT combined with MitoQ in rats with IPF and to explore the underlying mechanism. METHODS: Rat IPF model was established by endotracheal injection of 5 mg/kg BleomycinA5 into the specific pathogen-free SD rats. MitoQ (6.5 µmol/kg once daily), YFT (10 ml/kg once daily), and MitoQ + YFT (6.5 µmol/kg + 10 ml/kg once daily) were used to treat the rat model for 4 weeks, respectively. The normal rats without IPF were used as the controls. After 4 weeks of drug treatment, lung histopathology was assessed. Immunohistochemistry was used to detect the expression of fibronectin and collagen IV in lung tissue. The expression of IL-6, IL-1ß, TNF-α, GSH-Px, SOD, MDA, and hydroxyproline was determined by enzyme-linked immunosorbent assay. The expressions of TGFß1, NOX4, PDGFR-ß, and ROCK1 were determined using real-time quantitative PCR and Western blot. RESULTS: After 4 weeks of drug treatment, comparison of the MitoQ + YFT group with the IPF group showed that lung injury scores, W/D, lung tissue hydroxyproline, fibronectin, collagen IV content, and IL-6, IL-1ß, TNF-α, and MDA levels were significantly lower (P < 0.05), as well as the expression of TGFß1, NOX4, PDGFR-ß, and ROCK1, but the activity of GSH-Px and SOD was higher (P < 0.05). CONCLUSION: MitoQ combined with YFT can improve lung injury in rats with pulmonary fibrosis by reducing the secretion of proinflammatory cytokines and inhibiting TGFß1/NOX4 and PDGF/ROCK signaling pathways. It may provide a new method for the treatment of pulmonary fibrosis.

11.
Phys Rev Lett ; 126(20): 206404, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34110216

RESUMO

Higher-order topological insulators are established as topological crystalline insulators protected by crystalline symmetries. One celebrated example is the second-order topological insulator in three dimensions that hosts chiral hinge modes protected by crystalline symmetries. Since amorphous solids are ubiquitous, it is important to ask whether such a second-order topological insulator can exist in an amorphous system without any spatial order. Here, we predict the existence of a second-order topological insulating phase in an amorphous system without any crystalline symmetry. Such a topological phase manifests in the winding number of the quadrupole moment, the quantized longitudinal conductance, and the hinge states. Furthermore, in stark contrast to the viewpoint that structural disorder should be detrimental to the higher-order topological phase, we remarkably find that structural disorder can induce a second-order topological insulator from a topologically trivial phase in a regular geometry. We finally demonstrate the existence of a second-order topological phase in amorphous systems with time-reversal symmetry.

12.
Nanomaterials (Basel) ; 11(1)2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33435592

RESUMO

For the development of spacecraft with long-servicing life in low earth orbit (LEO), high-temperature resistant polymer films with long-term atomic oxygen (AO) resistant features are highly desired. The relatively poor AO resistance of standard polyimide (PI) films greatly limited their applications in LEO spacecraft. In this work, we successfully prepared a series of novel AO resistant PI composite films containing nanocaged polyhedral oligomeric silsesquioxane (POSS) components in both the PI matrix and the fillers. The POSS-containing PI matrix film was prepared from a POSS-substituted aromatic diamine, N-[(heptaisobutyl-POSS)propyl]-3,5-diaminobenzamide (DABA-POSS) and a common aromatic diamine, 4,4'-oxydianline (ODA) and the aromatic dianhydride, pyromellitic dianhydride (PMDA) by a two-step thermal imidization procedure. The POSS-containing filler, trisilanolphenyl POSS (TSP-POSS) was added with the fixed proportion of 20 wt% in the final films. Incorporation of TSP-POSS additive apparently improved the thermal stability, but decreased the high-temperature dimensional stable nature of the PI composite films. The 5% weight loss temperature (T5%) of POSS-PI-20 with 20 wt% of DABA-POSS is 564 °C, and its coefficient of linear thermal expansion (CTE) is 81.0 × 10-6/K. The former is 16 °C lower and the latter was 20.0 × 10-6/K higher than those of the POSS-PI-10 film (T5% = 580 °C, CTE = 61.0 × 10-6/K), respectively. POSS components endowed the PI composite films excellent AO resistance and self-healing characteristics in AO environments. POSS-PI-30 exhibits the lowest AO erosion yield (Es) of 1.64 × 10-26 cm3/atom under AO exposure with a flux of 2.51 × 1021 atoms/cm2, which is more than two orders of magnitude lower than the referenced PI (PMDA-ODA) film. Inert silica or silicate passivation layers were detected on the surface of the PI composite films exposed to AO.

13.
Phys Rev Lett ; 127(26): 263004, 2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35029461

RESUMO

Recent theoretical studies predict that structural disorder, serving as a bridge connecting a crystalline material to an amorphous material, can induce a topological insulator from a trivial phase. However, to experimentally observe such a topological phase transition is very challenging due to the difficulty in controlling structural disorder in a quantum material. Given experimental realization of randomly positioned Rydberg atoms, such a system is naturally suited to studying structural disorder induced topological phase transitions and topological amorphous phases. Motivated by the development, we study topological phases in an experimentally accessible one-dimensional amorphous Rydberg atom chain with random atom configurations. In the single-particle level, we find symmetry-protected topological amorphous insulators and a structural disorder induced topological phase transition, indicating that Rydberg atoms provide an ideal platform to experimentally observe the phenomenon using state-of-the-art technologies. Furthermore, we predict the existence of a gapless symmetry-protected topological phase of interacting bosons in the experimentally accessible system. The resultant many-body topological amorphous phase is characterized by a Z_{2} invariant.

14.
Brain Res ; 1748: 147070, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32827549

RESUMO

Hypoxic-ischemic encephalopathy (HIE) results in high neonatal mortality and severe neurological impairments, and its underlying molecular mechanism underwent extensive investigations. Long non-coding RNA (lncRNA) is considered to be an important regulator on brain development and many neurological diseases. Currently, little is known about the role of Vof-16 (lncRNA) in HIE. We detected the relative expression level of Vof-16 in the cortex and hippocampus of hypoxic-ischemic (HI) models whose successful establishment was verified by TTC staining. Then, Vof-16 knockout rats were generated using the CRISPR/Cas engineering technology to search the specific function of the Vof-16 through a series of behavioral evaluations including Neurological severity scores (NSS), Y-maze test, Morris water maze (MWW) test, open field test, and Rotarod test. The results demonstrated the expression of Vof-16 was substantially up-regulated in the cortex and hippocampus of rats with HI injury. Importantly, Vof-16 knockout facilitated the recovery from long-term HI induced nerve damage and neurobehavioral dysfunctions. In conclusion, this study suggests Vof-16 knockout is a promising treatment target for neonatal HIE.


Assuntos
Encéfalo/metabolismo , Hipóxia-Isquemia Encefálica/genética , Proteínas/genética , Recuperação de Função Fisiológica/fisiologia , Animais , Animais Recém-Nascidos , Sistemas CRISPR-Cas , Técnicas de Inativação de Genes , Hipóxia-Isquemia Encefálica/metabolismo , Aprendizagem em Labirinto/fisiologia , Atividade Motora/fisiologia , Proteínas/metabolismo , Ratos , Ratos Sprague-Dawley
15.
Phys Rev Lett ; 123(7): 076401, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31491126

RESUMO

We study amorphous systems with completely random sites and find that, through constructing and exploring a concrete model Hamiltonian, such a system can host an exotic phase of topological amorphous metal in three dimensions. In contrast to the traditional Weyl semimetals, topological amorphous metals break translational symmetry, and thus they cannot be characterized by the first Chern number defined based on the momentum space band structures. Instead, their topological properties will manifest in the Bott index and the Hall conductivity as well as the surface states. By studying the energy band and quantum transport properties, we find that topological amorphous metals exhibit a diffusive metal behavior. We further introduce a practical experimental proposal with electric circuits where the predicted phenomena can be observed using state-of-the-art technologies. Our results open the door to exploring topological gapless phenomena in amorphous systems.

16.
Polymers (Basel) ; 11(6)2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31181709

RESUMO

Protection of polymeric materials from the atomic oxygen erosion in low-earth orbit spacecrafts has become one of the most important research topics in aerospace science. In the current research, a series of novel organic/inorganic nanocomposite films with excellent atomic oxygen (AO) resistance are prepared from the phosphorous-containing polyimide (FPI) matrix and trisilanolphenyl polyhedral oligomeric silsesquioxane (TSP-POSS) additive. The PI matrix derived from 2,2'-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA) and 2,5-bis[(4-amino- phenoxy)phenyl]diphenylphosphine oxide (BADPO) itself possesses the self-healing feature in AO environment. Incorporation of TSP-POSS further enhances the AO resistance of the FPI/TSP composite films via a Si-P synergic effect. Meanwhile, the thermal stability of the pristine film is maintained. The FPI-25 composite film with a 25 wt % loading of TSP-POSS in the FPI matrix exhibits an AO erosion yield of 3.1 × 10-26 cm3/atom after an AO attack of 4.0 × 1020 atoms/cm2, which is only 5.8% and 1.0% that of pristine FPI-0 film (6FDA-BADPO) and PI-ref (PMDA-ODA) film derived from 1,2,4,5-pyromellitic anhydride (PMDA) and 4,4'-oxydianline (ODA), respectively. Inert phosphorous and silicon-containing passivation layers are observed at the surface of films during AO exposure.

17.
Syst Parasitol ; 96(3): 337-346, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30903446

RESUMO

We examined faeces of 76 endangered Tibetan antelopes Pantholops hodgsonii (Abel) in May 2017, from the Hoh Xil Nature Reserve, Qinghai Province, China, and found 62/76 (82%) discharging oöcysts representing five new species of Eimeria Schneider, 1875. Oöcysts of Eimeria pantholopensis n. sp., found in 54/76 (71%) chiru, are subspheroidal/ellipsoidal, 15-22 × 12-19 (18.6 × 16.1) µm, with a length/width (L/W) ratio of 1.0-1.3 (1.2); micropyle cap and 1-3 polar granules are present, but oöcyst residuum is absent. Sporocysts are ovoidal, 7-11 × 4-6 (9.2 × 5.3) µm, with a L/W ratio of 1.6-2.0 (1.7); Stieda body and sporocyst residuum of small, scattered granules are present; each sporozoite contains 2 refractile bodies. Oöcysts of Eimeria wudaoliangensis n. sp. found in 52/76 (68%) chiru, are pyriform, 21-29 × 17-21 (24.9 × 19.0) µm, with a L/W ratio of 1.1-1.5 (1.3); micropyle, micropyle cap and 1-4 polar granules are present, but oöcyst residuum is absent. Sporocysts are ovoidal, 9-13 × 5-8 (11.7 × 6.7) µm, with a L/W ratio of 1.4-2.7 (1.7); Stieda body and sporocyst residuum of disbursed granules are present; sporozoites have a single large refractile body. Oöcysts of Eimeria hodgsonii n. sp. found in 20/76 (26%) chiru, are elongate-ellipsoidal, 25-32 × 18-21 (28.9 × 19.8) µm, with a L/W ratio of 1.2-1.7 (1.5); micropyle, micropyle cap and 1-3 polar granules are present, but oöcyst residuum is absent. Sporocysts are ovoidal, 11-14 × 6-7 (12.3 × 6.8) µm, with a L/W ratio of 1.7-2.1 (1.8); Stieda body and sporocyst residuum as group of large granules lying along the interface between intertwined sporozoites are present; sporozoites have 2 refractile bodies. Oöcysts of Eimeria schalleri n. sp. found in 49/76 (64.5%) chiru, are ellipsoidal, 26-36 × 19-25 (30.4 × 23.2) µm, with a L/W ratio of 1.2-1.5 (1.3); micropyle with micropyle cap and polar granules appearing as many diffuse tiny bodies are present, but oöcyst residuum is absent. Sporocysts are ovoidal, 12-16 × 7-9 (14.2 × 7.8) µm, with a L/W ratio of 1.6-2.1 (1.8); Stieda body and sporocyst residuum are present, the latter as a group of small dispersed granules between intertwined sporozoites; sporozoites with 2 refractile bodies. Oöcysts of Eimeria sui n. sp. found in 4/76 (5%) chiru, are ovoidal, 32-38 × 26-30 (36.6 × 28.6) µm, with a L/W ratio of 1.0-1.4 (1.3); micropyle and micropyle cap and 1-3 polar granules are present, but oöcyst residuum is absent. Sporocysts are ovoidal, 15-18 × 8-10 (16.7 × 8.9) µm, with a L/W ratio of 1.7-2.1 (1.9); Stieda body and sporocyst residuum are present, the latter as a group of dispersed small granules; sporozoites with 2 refractile bodies. Five of 62 faecal samples in which oöcysts were detected (8%) had a single species infection, 13 of 62 (21%) had two species, 28 of 62 (45%) had three species and 16 of 62 (26%) had four species.


Assuntos
Antílopes/parasitologia , Coccidiose/parasitologia , Eimeria/classificação , Animais , China/epidemiologia , Coccidiose/epidemiologia , Eimeria/citologia , Fezes/parasitologia , Especificidade da Espécie
18.
J Wildl Dis ; 52(4): 945-948, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27458832

RESUMO

We used a flotation technique to survey fecal samples from 27 Przewalski's gazelles ( Procapra przewalskii Büchner, 1891) for intestinal parasites. Samples were collected from the Qinghai Lake region, Qinghai-Tibet plateau, China, in April 2015. We report parasites belonging to two nematode (Nematodirus, Marshallagia) genera and one apicomplexan (Eimeria) genus; one of the latter was a new species from the critically endangered Przewalski's gazelle. Sporulated oocysts of the new eimerian were spheroidal; they had a thick, outer wall without a micropyle, but with a distinct polar granule and an oocyst residuum. Oocysts measured a mean of 18.6(±0.8)×17.3(±0.9) µm in length and width, with a mean 1.1(±0.1) length/width ratio and a spheroidal oocyst residuum that had a mean width of 2.0(±0.7) µm. Sporocysts were ovoid, measuring a mean of 9.4(±0.6)×5.5(±0.5) µm in length and width, with a mean 1.7(±0.2) length/width ratio. A Stieda body and sporocyst residuum were present, but a substieda body was absent. Sporozoites each had a small anterior refractile body and a larger, posterior refractile body; a small nucleus was visible between them.


Assuntos
Coccidiose/veterinária , Eimeria/patogenicidade , Ruminantes/microbiologia , Animais , China , Parasitos , Tibet
19.
Zhongguo Zhen Jiu ; 34(4): 385-8, 2014 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-24946646

RESUMO

OBJECTIVE: To compare the effects on anesthesia recovery between assisted-electroacupuncture fast tracking anesthesia and simple fast tracking anesthesia in patients with minim ally invasive percutaneous nephrolithotomy (mPCNL). METHODS: Eighty cases of mPCNL were selected and randomly divided into a treatment group and a control group. Fentanyl (1-2 microg/kg), sevoflurane (8%) and rocuronium (0.5 mg/kg) were applied to perform anesthesia induction in both groups, and endotracheal inhalation of sevoflurane and intravenous pump injection of remifentanil were adopted to main anesthesia status during the operation. 20 min before anesthesia induction, bilateral Neiguan (PC 6), Neimadian, Hegu (LI 4), Yangxi (LI 5), Zhongji (CV 3), Qichong (ST 30), Zuwuli (LR 10) were selected and punctured in the treatment group, and elecctroacupuncture was given after arrival of qi until 30 min after the wake-up from anesthesia and withdrawal of endotracheal tube. The dosage for anesthesia maintenance, recovery time of awareness, extubation time, incidences of nausea, vomiting and chill and irritation of urethral catheters were observed and recorded. RESULTS: (1) The dosages of remifentanil and sevoflurane in the treatment group during the operation were obviously less than those in the control group [remifentanil: (5. 27 +/-1.23) micro g/kg h vs (7.35+/-1.70) micro g/kg . h; sevoflurane: (1.12+/-0.43) vol% vs (2.35+/-0.87) vol% , both P<0. 001]. (2) The recovery time of awareness and extubation time in the treatment group were significantly earlier than those in the control group [recovery time of awareness: (5.65 +/- 2.34) min vs (8. 87 +/- 6. 84) min, P<0. 01; extubation time : (7. 23+/-4. 35) min vs (10. 62+/-8. 16) min, P<0. 05]. (3) The incidences of nausea, vomiting and chill in the treatment group were significantly less than those in the control group (all P<0. 05). (4) The irritation of urethral catheters on urethra in the treatment group was significantly less than that in the control group (P<0. 001). CONCLUSION: The assisted-electroacupuncture anesthesia could reduce the dosage of remifentanil and sevoflurane in mPCNL fast tracking anesthesia in urinary surgery, reduce the incidences of nausea, vomiting, chill and irritation of urethral catheters during recovery stage, and prompt recovery of mPCNL patients.


Assuntos
Período de Recuperação da Anestesia , Anestésicos Intravenosos/efeitos adversos , Eletroacupuntura , Náusea e Vômito Pós-Operatórios/terapia , Adolescente , Adulto , Anestésicos Intravenosos/administração & dosagem , Feminino , Fentanila/administração & dosagem , Fentanila/efeitos adversos , Humanos , Masculino , Éteres Metílicos/administração & dosagem , Éteres Metílicos/efeitos adversos , Pessoa de Meia-Idade , Nefrostomia Percutânea , Piperidinas/administração & dosagem , Piperidinas/efeitos adversos , Remifentanil , Sevoflurano , Adulto Jovem
20.
Nan Fang Yi Ke Da Xue Xue Bao ; 32(12): 1804-7, 2012 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-23268415

RESUMO

OBJECTIVE: To investigate the genetic variation and typing of hepatitis B virus (HBV) in patients with chronic hepatitis B in relation to HBeAg status. METHODS: Fluorescence quantitative polymerase chain reaction (PCR) was employed to detect serum HBV DNA in patients with chronic hepatitis B negative for HBeAg. Real-time fluorescent PCR and PCR-reverse dot blot hybridization were used to detect HBV genotypes and mutations, respectively. RESULTS: Of the 389 patients, 214 (55.01%) were positive and 175 (44.99%) were negative for HBV DNA; 102 (26.22%) had a HBV DNA copy number of 1×10(3), and 41 (10.54%) had a copy number of 1×10(4) (Χ(2)=226.6729, P<0.001). Of the 21 patients with a HBV DNA load of 1×10(5), 15 (71.43%) were found to have precore mutations, and 11 (52.38%) had basic core promoter (BCP) mutations; a higher HBV-DNA load was associated with an increased incidence of HBV mutations. In the 214 patients positive for HBV DNA, HBV genotypes A, B, C, D and the mixed type were found in 6 (2.80%), 84 (39.25%), 106 (49.53%), and 7 (3.27%), and 11 (5.14%) patients, who showed precore mutation rates of 16.67% (1 case), 36.90% (31 cases), 44.34% (47 cases), 0, and 0, and BCP mutation rates of 0, 19.05% ( 16 cases), 26.42% (28 cases), 0, and 0, respectively, demonstrating significant differences in HBV mutations between the genotype groups (P<0.001). CONCLUSION: HBeAg-negative and HBV DNA-positive patients with chronic hepatitis B have a relatively low HBV replication level, and HBV DNA load is associated with HBV mutations. The B and C genotypes are more likely to have HBV mutations in HBeAg-negative patients.


Assuntos
Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , DNA Viral/sangue , Feminino , Genótipo , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/classificação , Hepatite B Crônica/sangue , Humanos , Masculino , Mutação , Regiões Promotoras Genéticas , Proteínas do Core Viral/genética , Carga Viral
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