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1.
Phys Chem Chem Phys ; 25(2): 1331-1341, 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36533691

RESUMO

N2 fixation is very difficult because of the nonpolarity and high stability of N2. Traditionally, it is achieved by transition metal (TM) systems utilizing the back donation from the d orbitals of the TM to the antibonding π* orbitals of N2 to activate N2. This back donation is rare for main group compounds due to the lack of high-lying valence d orbitals. In the present study, we show that borane compounds with weak B-X (X = H, Si, Ge, and Sb) bonds can mimic TM systems and be used to fix and activate N2. This is achieved by the back donation from the σ bonding orbitals of the B-X bonds to the antibonding π* and σ* orbitals of N2. There is even a linear relationship between the number of B-X bonds and the binding potential energy of N2 with BR1R2R3 (R1, R2, R3 = H, CH3, SiH3, GeH3, and SbH2). Based on these findings, we designed several stable silylborane compounds that are feasible for N2 fixation and activation under mild reaction conditions, i.e., room temperature and 1 atm. In some sandwich-like complexes formed between N2 and silylborane compounds, N2 is even activated from the triple bond to double bond.

2.
Mol Breed ; 41(12): 73, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37309520

RESUMO

Photo-(thermo-) sensitive genic male-sterile line is the key component of two-line hybridization system in foxtail millet (Setaria italica), but the genetic basis of male sterility in most male-sterile lines is still unclear. In the present study, a large F2 population was developed derived from a cross between the photo-(thermo-) sensitive male-sterile line A2 and the fertile-line 1484-5. Thirty plants with extreme high and extreme low fertility were selected from the population to construct a sterile DNA pool and a fertile DNA pool, respectively. Sequencing both DNA pools and data analysis revealed that two QTLs conferred male-sterility, qSiMS6.1 with a major effect and qSiMS6.2 with a minor effect, on chromosome 6. Both QTLs exhibited complete dominance. The major QTL, qSiMS6.1, was delimited to a 186-kb interval between the markers SiM20 and SiM9 by the joint analysis of QTL-seq and QTL mapping with SSR and structure variation markers. Millet_GLEAN_10020454 in this region is the most likely candidate gene for qSiMS6.1 since it is predicted to encode a male-sterile 5 like protein. These results lay a solid foundation for qSiMS6.1 cloning and provided gene resources for breeding new male-sterile lines. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-021-01269-2.

3.
J Chem Phys ; 151(10): 104311, 2019 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-31521070

RESUMO

We have employed extended multiconfiguration quasidegenerate perturbation theory, fourfold-way diabatic molecular orbitals, and configurational uniformity to develop a global three-state diabatic representation of the potential energy surfaces and their couplings for the electronically nonadiabatic reaction OH* + H2 → H2O + H, where * denotes electronic excitation to the A 2Σ+ state. To achieve sign consistency of the computed diabatic couplings, we developed a graphics processing unit-accelerated algorithm called the cluster-growing algorithm. Having obtained consistent signs of the diabatic couplings, we fit the diabatic matrix elements (which consist of the diabatic potentials and the diabatic couplings) to analytic representations. Adiabatic potential energy surfaces are generated by diagonalizing the 3 × 3 diabatic potential energy matrix. The comparisons between the fitted and computed diabatic matrix elements and between the originally computed adiabatic potential energy surfaces and those generated from the fits indicate that the current fit is accurate enough for dynamical studies, and it may be used for quantal or semiclassical dynamics calculations.

4.
Chemistry ; 24(50): 13238-13245, 2018 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-29938854

RESUMO

Ammonia borane (AB) has been in the spotlight for the chemical storage of hydrogen over the past decade. However, the development of methods for efficient and controlled hydrogen release from AB under mild conditions is still underway. Herein, using density functional theory (DFT) computations, we designed a metal-free frustrated Lewis pair (FLP) catalyst o-(BPh2 )C6 H4 (NiPr2 ) (M1) that can efficiently dehydrogenate AB to release more than two equivalents of H2 under mild conditions. Catalyst M1 can dehydrogenate not only AB to H2 N=BH2 (AOB) and H2 , but also oligomers of AOB with rather low free-energy barriers. The high dehydrogenation activity of M1 is the key of new oligomerization routes to the efficient dehydrogenation of AB to borazine (BZ) or H2 B-(NH=BH)n -NH2 (PIB) and finally to polyborazylene (PBZ) so that more than two equivalents of H2 can be released. A first-principle kinetic Monte Carlo (KMC) study reveals that the activity of our catalytic system can be tuned by varying the initial concentration of M1 and AB. This work can guide the design of catalyst for the highly efficient utilization of AB as a hydrogen storage material.

5.
Nutr Cancer ; 69(8): 1281-1289, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29111814

RESUMO

Sarsaparilla (Smilax Glabra Rhizome) exerts growth inhibitory effect on multiple cancer cells in vitro and in vivo, and redox-dependent persistent activation of ERK1/2 has been reported to underlie this effect. Here, we report an activation of ATM/ATR-dependent signaling pathway also as a mechanism for the cancer cell growth inhibition induced by the supernatant fraction of the water-soluble extract from sarsaparilla (SW). SW treatment (3.5 µg/µL) promoted the phosphorylations of ATM, ATR, and CHK1 in AGS and HT-29 cells. The ATM kinase inhibitor, KU55933, could reverse SW-induced ERK phosphorylation but not the reduced glutathione/oxidized glutathione (GSH/GSSG) imbalance in AGS cells. However, both the redox inhibitor glutathione (GSH) and ERK inhibitor U0126 antagonized SW-induced phosphorylations of ATM, ATR, and CHK1 in AGS cells. We further found KU55933 significantly antagonized SW-induced S phase arrest, apoptosis, autophagy and the resultant cell growth inhibition. Our results provide another molecular basis for the anticancer action of sarsaparilla.


Assuntos
Apoptose/efeitos dos fármacos , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Autofagia/efeitos dos fármacos , Extratos Vegetais/farmacologia , Smilax/química , Proteínas Mutadas de Ataxia Telangiectasia/genética , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Glutationa/metabolismo , Dissulfeto de Glutationa/metabolismo , Células HT29 , Humanos , Morfolinas/farmacologia , Oxirredução/efeitos dos fármacos , Pironas/farmacologia , Rizoma/química , Fase S , Transdução de Sinais
6.
Phys Chem Chem Phys ; 19(41): 28313-28322, 2017 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-29034387

RESUMO

A strategy for the reduction of CO2 to CO by or catalyzed by metal-free silylboranes has been proposed with the aid of density functional theory (DFT) computations. We showed that one oxygen atom of CO2 can be abstracted by silylboranes without catalysts or by diboranes in the presence of silylborane catalysts with surprisingly low free-energy barriers so that the reaction can be realized under mild experimental conditions. To achieve this, the reduction mechanism of CO2 by a hierarchy of silylboranes (R1)2BSi(R2)3 was systematically investigated. Several rules of thumb were obtained to guide the design of silylboranes with high activity toward CO2 reduction. After considering many factors, such as side reactions, the stability of the silylboranes, and the solvent effect, two silylboranes, (PFP)2BSi(CH2F)3 and Me2BSi(CH2F)3, suitable for the reduction of CO2 under mild experimental conditions were designed. The overall free-energy barriers for the reduction of CO2 by the two silylboranes are just 26.1-27.0 kcal mol-1 and 28.1-28.9 kcal mol-1, respectively, at 298.15 K in solution. We further showed that CO2 can be reduced to CO by diborane Me2BBMe2 using Me2BSi(CH2F)3 as the catalyst. The overall free-energy barrier for this catalytic reaction is just 30.6-30.7 kcal mol-1 at 298.15 K in solution.

8.
J Chem Phys ; 147(3): 034301, 2017 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-28734300

RESUMO

We present global ground-state potential energy surfaces for the quintet and singlet spin states of the O4 system that are suitable for treating high-energy vibrational-rotational energy transfer and collision-induced dissociation in electronically adiabatic, spin-conserving O2-O2 collisions. The surfaces are based on MS-CASPT2/maug-cc-pVTZ electronic structure calculations with scaled external correlation. The active space has 16 electrons in 12 orbitals. The calculations cover nine kinds of geometrical arrangements corresponding to dissociative diatom-diatom collisions of O2, geometries corresponding to O3-O, geometries identified by running trajectories, and geometries along linear synchronous transit paths. The global ground-state potential energy surfaces were obtained by a many-body approach with an accurate O-O pairwise interaction and a fit of the many-body interaction to 12 684 electronic structure data points for the singlet and 10 543 electronic structure data points for the quintet. The many-body fit is based on permutationally invariant polynomials in terms of bond-order functions of the six interatomic distances; the bond-order functions are mixed exponential-Gaussian functions.

9.
J Chem Phys ; 144(2): 024309, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26772573

RESUMO

This work presents two global triplet potential energy surfaces (PESs) for the high-energy reaction N2(X(1)Σ) + O((3)P) → NO(X(2)Π) + N((4)S)-in particular, for the lowest energy (3)A' and (3)A″ PESs. In order to obtain the energies needed for fitting analytic surfaces, we carried out multireference configuration interaction (MRCI) calculations based on wave functions obtained from state-averaged complete active space self-consistent field calculations for 2280 geometries for the three lowest (3)A″ states and for 2298 geometries for the three lowest (3)A' states. The lowest-energy (3)A' and (3)A″ states at each of these geometries were then improved by applying the dynamically scaled external correlation (DSEC) method to all MRCI points, and the resulting DSEC energies were used for construction of the ground-state PES for each symmetry. The many-body component of the DSEC energies for the three-dimensional (3)A' and (3)A″ PESs was then least-squares fitted in terms of permutationally invariant polynomials in mixed exponential-Gaussian bond order variables. The global and local minima as well as the transition structures of both the (3)A' and the (3)A″ analytic PES were explored. In agreement with previous work, we find that the reverse reaction is barrierless on the (3)A″ surface along the minimum energy pathway. However, we have explored several new local minima and transition structures on the (3)A' PES. Furthermore, based on the newly found minima and transition structures, two independent reaction mechanisms have been illustrated for the reaction path on the (3)A' PES. The analytic surfaces may be used for dynamics calculations of electronically adiabatic reactive scattering and energy transfer.

10.
J Chem Phys ; 144(2): 024310, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26772574

RESUMO

We present a global ground-state triplet potential energy surface for the N2O2 system that is suitable for treating high-energy vibrational-rotational energy transfer and collision-induced dissociation. The surface is based on multi-state complete-active-space second-order perturbation theory/minimally augmented correlation-consistent polarized valence triple-zeta electronic structure calculations plus dynamically scaled external correlation. In the multireference calculations, the active space has 14 electrons in 12 orbitals. The calculations cover nine arrangements corresponding to dissociative diatom-diatom collisions of N2, O2, and nitric oxide (NO), the interaction of a triatomic molecule (N2O and NO2) with the fourth atom, and the interaction of a diatomic molecule with a single atom (i.e., the triatomic subsystems). The global ground-state potential energy surface was obtained by fitting the many-body interaction to 54 889 electronic structure data points with a fitting function that is a permutationally invariant polynomial in terms of bond-order functions of the six interatomic distances.

11.
Cytokine ; 68(2): 69-75, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24845795

RESUMO

BACKGROUND: Th1/Th17 imbalance had been indicated to mediate several kinds of inflammatory diseases. We deduce that Th1/Th17 imbalance might also contribute to the pathogenesis of acute graft-versus-host disease (GVHD). This study is to investigate the relation between Th1/Th17 imbalance and acute GVHD. METHODS: We applied a murine GVHD model of C57BL/6 (H-2(b)) donor to BALB/c (H-2(d)) recipient by treating the recipients with low dose of halofuginone (HF), which is competent in selectively inhibiting Th17 differentiation and facilitating Th1 differentiation. Recipient mice were monitored for survival rate, body weight change, clinical symptoms and pathological evidence of acute GVHD. We also measured the proportions of Th1 and Th17 cells in circulation and expression levels of IFN-γ and IL-17A in tissues involved in GVHD. RESULTS: Firstly, we confirm the existence of Th1/Th17 imbalance in acute GVHD and Th1/Th17 imbalance positively correlates with severity of acute GVHD. Secondly, low dose of HF augments Th1/Th17 imbalance by driving the Th1/Th17 balance to a Th1-dominant reaction. Finally, augmented Th1/Th17 imbalance leads to aggravated systemic GVHD. An increased Th1-type reaction results in aggravated hepatic and intestinal GVHD, and inhibiting Th17 differentiation is sufficient to alleviate pulmonic impairment. CONCLUSION: Our study is indicative for a critical role of Th1/Th17 imbalance in the pathogenesis of murine GVHD.


Assuntos
Progressão da Doença , Doença Enxerto-Hospedeiro/imunologia , Células Th1/imunologia , Células Th17/imunologia , Doença Aguda , Animais , Interferon gama/metabolismo , Interleucina-17/metabolismo , Contagem de Linfócitos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Especificidade de Órgãos/efeitos dos fármacos , Piperidinas/administração & dosagem , Piperidinas/farmacologia , Quinazolinonas/administração & dosagem , Quinazolinonas/farmacologia
12.
ACS Omega ; 9(13): 14747-14765, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38585095

RESUMO

With the increasing oil demand, more attention has been paid to enhancing oil recovery in old oil fields. CO2 flooding is popular due to its high oil displacement efficiency and ability to reduce greenhouse gas emissions. Laboratory experiments and on-site application cases have shown that the minimum miscibility pressure has a greater impact on CO2 flooding than other factors. If the reservoir pressure is below the minimum miscible pressure, then there is CO2 immiscible flooding. Both theoretical analysis and experimental results show that the recovery rate of CO2 miscible flooding is 2-5 times higher than that of immiscible flooding. If the reservoir pressure is increased by water flooding before CO2 injection, it is easily limited by the physical property parameters. Therefore, accurately determining and effectively reducing the minimum mixing pressure has become the focus of research. Currently, there are two types of methods for determining the minimum miscible pressure: experimental and theoretical methods. The experimental method is generally considered more accurate, including the slim tube test, rising bubble apparatus, and vanishing interfacial tension, etc. However, it is worth noting that the minimum miscibility pressure is dynamically changing, and there will be high economic costs if measured repeatedly through experimental methods during reservoir development. Therefore, it is recognized that the minimum mixing pressure can be determined at any time using theoretical calculation of initial data, which will reduce economic and time costs to a high degree. In this paper, the theoretical calculation method is divided into empirical correlation, state equation, and artificial intelligence algorithm. The techniques for reducing the minimum miscibility pressure can be classified into two categories: miscible solvents and surfactant methods. The miscible solvent method can be further divided into monocomponent and polycomponent methods. This paper compares the advantages and disadvantages of the existing techniques for measuring and reducing MMP and selects the best method.

13.
Life Sci ; 312: 121207, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36403642

RESUMO

Trastuzumab (TZM) is commonly used for target therapy in breast cancer patients with high HER2 although the cardiotoxicity restricts its clinical usage. DNA damage and ferroptosis are implicated in anti-tumor drug cardiotoxicity. Given the emerging use of SGLT2 inhibitors in clinical cardiology, this study evaluated the impact of SGLT2 inhibitor Empagliflozin on TZM-induced cardiotoxicity, and mechanism involved with a focus on DNA damage and ferroptosis. Adult C57BL/6 mice were challenged with TZM (10 mg/kg/week, i.p.) or saline for six weeks. A cohort of mice received Empagliflozin (10 mg/kg, i.p.) at the same time. Myocardial function, morphology, ultrastructure, mitochondrial integrity, oxidative stress, DNA damage and various cell death domains were evaluated in TZM-challenged mice with or without Empagliflozin treatment. Our data revealed that TZM challenge overtly increased levels of serum LDH and troponin I, promoted adverse myocardial remodeling (increased heart weight, chamber size, cardiomyocyte area and interstitial fibrosis), contractile dysfunction and intracellular Ca2+ mishandling, oxidative stress, lipid peroxidation, mitochondrial ultrastructural damage, DNA damage, apoptosis and ferroptosis, the effects of which were greatly attenuated or mitigated by Empagliflozin with little effects from Empagliflozin itself. In vitro study indicated that induction of DNA damage mimicked TZM-induced lipid peroxidation and cardiomyocyte contractile dysfunction while the ferroptosis inducer erastin mitigated Empagliflozin-offered protection against lipid peroxidation and cardiomyocyte dysfunction (but not DNA damage). Likewise, in vivo and in vitro inhibition of ferroptosis recapitulated Empagliflozin-offered cardioprotection against TZM exposure. Taken together, these data demonstrated that Empagliflozin may be possible candidate drug for TZM cardiotoxicity likely through a DNA damage-ferroptosis-mediated mechanism.


Assuntos
Ferroptose , Inibidores do Transportador 2 de Sódio-Glicose , Camundongos , Animais , Cardiotoxicidade/etiologia , Cardiotoxicidade/prevenção & controle , Trastuzumab/farmacologia , Camundongos Endogâmicos C57BL , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Dano ao DNA
14.
ACS Omega ; 7(2): 2391-2397, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35071926

RESUMO

Through theoretical computations, we found that boron can form thermodynamically stable pentacoordinate compounds. Pentacoordinate boron (penta-B) is just hypercoordinate but not hypervalent because it forms only four covalent bonds, of which at least one is a multicenter bond. Being electron deficient, to be pentacoordinate, at least two of its bonding atoms should have low electronegativity. Penta-B can be formed in H k B(CH3) m (XH3) n (X = Si, Ge, Sn, and n ≥ 2) and BR5 (R = BH2NH3, AsH2, and BeH). Based on a systematic investigation of these model compounds, we designed three thermodynamically stable penta-B compounds that can potentially be synthesized by hydrogenating their tricoordinate counterparts under mild reaction conditions.

15.
Waste Manag ; 137: 72-80, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34749179

RESUMO

In order to achieve thermal treatment of coal slime and depth control of NOx, a 75 t/h circulating fluidized bed (CFB) boiler arranging post-combustion air is constructed. In the experiment, the combustion atmosphere and the ratio of primary air and secondary air are adjusted to decrease the NOx emissions below 50 mg/m3 (dry basis at 6% O2). Compared with conventional CFB combustion, the post-combustion technology decreases the NOx emissions from 92.9 to 65.4 mg/m3 by adjusting the combustion atmosphere. Then, the primary air volume is adjusted to decrease the NOx emissions further. On the one hand, decreasing primary air volume contributes to inhibiting the NOx generation in the dense phase. On the other hand, it is proved that the combination of the cyclone and a post-combustion chamber plays a crucial role in the de-NOx process of post-combustion technology. More char particles are brought to the cyclone as the primary air volume decreases. The NOx reduction in the cyclone and the post-combustion chamber is promoted. Finally, the NOx emissions are decreased to 42.6 mg/m3 when the ratio of primary air and secondary air is 50.0%. In addition, the SO2 emissions and the combustion efficiency during the ultra-low NOx condition are 23.2 mg/m3 and 98.3%, respectively.


Assuntos
Poluentes Atmosféricos , Carvão Mineral , Poluentes Atmosféricos/análise , Atmosfera , Carvão Mineral/análise , Resíduos Sólidos , Tecnologia
16.
Biochim Biophys Acta Gen Subj ; 1866(12): 130245, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36126834

RESUMO

BACKGROUND: Binge drinking leads to compromised mitochondrial integrity and contractile function in the heart although little effective remedy is readily available. Given the possible derangement of autophagy in ethanol-induced cardiac anomalies, this study was designed to examine involvement of Beclin1 in acute ethanol-induced cardiac contractile dysfunction, in any, and the impact of Beclin1 haploinsufficiency on ethanol cardiotoxicity with a focus on autophagy-related ferroptosis. METHODS: WT and Beclin1 haploinsufficiency (BECN+/-) mice were challenged with ethanol for one week (2 g/kg, i.p. on day 1, 3 and 7) prior to assessment of cardiac injury markers (LDH, CK-MB), cardiac geometry, contractile and mitochondrial integrity, oxidative stress, lipid peroxidation, apoptosis and ferroptosis. RESULTS: Ethanol exposure compromised cardiac geometry and contractile function accompanied with upregulated Beclin1 and autophagy, mitochondrial injury, oxidative stress, lipid peroxidation and apoptosis, and ferroptosis (GPx4, SLC7A11, NCOA4). Although Beclin1 deficiency did not affect cardiac function in the absence of ethanol challenge, it alleviated ethanol-induced changes in cardiac injury biomarkers, cardiomyocyte area, interstitial fibrosis, echocardiographic and cardiomyocyte mechanical properties along with mitochondrial integrity, oxidative stress, lipid peroxidation, apoptosis and ferroptosis. Ethanol challenge evoked pronounced ferroptosis (downregulated GPx4, SLC7A11 and elevated NCOA4, lipid peroxidation), the effect was alleviated by Beclin1 haploinsufficiency. Inhibition of ferroptosis using LIP-1 rescued ethanol-induced cardiac mechanical anomalies. In vitro study noted that ferroptosis induction using erastin abrogated Beclin1 haploinsufficiency-induced response against ethanol. CONCLUSIONS: In sum, our data suggest that Beclin1 haploinsufficiency benefits acute ethanol challenge-induced myocardial remodeling and contractile dysfunction through ferroptosis-mediated manner.


Assuntos
Ferroptose , Cardiopatias , Camundongos , Animais , Proteína Beclina-1/genética , Proteína Beclina-1/farmacologia , Miócitos Cardíacos , Etanol/toxicidade
17.
Front Plant Sci ; 13: 1035906, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36704173

RESUMO

As a bridge between genome and phenotype, metabolome is closely related to plant growth and development. However, the research on the combination of genome, metabolome and multiple agronomic traits in foxtail millet (Setaria italica) is insufficient. Here, based on the linkage analysis of 3,452 metabolites via with high-quality genetic linkage maps, we detected a total of 1,049 metabolic quantitative trait loci (mQTLs) distributed in 11 hotspots, and 28 metabolite-related candidate genes were mined from 14 mQTLs. In addition, 136 single-environment phenotypic QTL (pQTLs) related to 63 phenotypes were identified by linkage analysis, and there were 12 hotspots on these pQTLs. We futher dissected 39 candidate genes related to agronomic traits through metabolite-phenotype correlation and gene function analysis, including Sd1 semidwarf gene, which can affect plant height by regulating GA synthesis. Combined correlation network and QTL analysis, we found that flavonoid-lignin pathway maybe closely related to plant architecture and yield in foxtail millet. For example, the correlation coefficient between apigenin 7-rutinoside and stem diameter reached 0.98, and they were co-located at 41.33-44.15 Mb of chromosome 5, further gene function analysis revealed that 5 flavonoid pathway genes, as well as Sd1, were located in this interval . Therefore, the correlation and co-localization between flavonoid-lignins and plant architecture may be due to the close linkage of their regulatory genes in millet. Besides, we also found that a combination of genomic and metabolomic for BLUP analysis can better predict plant agronomic traits than genomic or metabolomic data, independently. In conclusion, the combined analysis of mQTL and pQTL in millet have linked genetic, metabolic and agronomic traits, and is of great significance for metabolite-related molecular assisted breeding.

18.
Front Plant Sci ; 13: 1008198, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36212350

RESUMO

Sorghum [Sorghum bicolor (L.) Moench] is an important crop for food security in semiarid and arid regions due to its high tolerance to abiotic and biotic stresses and its good performance in marginal lands with relatively low fertility. To deeply understand the interrelationship among sorghum genotype, environment, sowing dates, and densities in the spring sowing early maturing (SSEM) areas of China, and to provide a basis for specifying scientific and reasonable cultural practices, a two-year field experiment was conducted with six popular varieties at six locations. Combined ANOVA showed that the yield difference between years was significant (P<0.05); the yield differences among locations, varieties, sowing dates, and densities were all highly significant (P<0.01). The variety effect was mainly influenced by location, year, sowing dates and their interactions. The sowing effect was mainly influenced by the location, year, variety and their interactions The plant density effect was significantly influenced by location and location-year interaction. Of the contributions of various test factors to yield variance, the location was the largest one (38.18%), followed by variety (12.31%), sowing date (1.53%), density (0.54%), and year (0.09%), with all these single factors accounting for 52.65%. The total contribution of all two-factor interactions accounted for 14.24%, among which the greatest contributor was location-hybrid interaction (8.07%). The total contribution of all three-factor interactions accounted for 14.58%, of which year-location-hybrid interaction was the largest contributor (9.02%). Sowing dates significantly affected model of sorghum growth and development, especially during the late period. The key climatic factors affecting yield were different among the six locations. Weather factors during the grain filling stages contributed much more than those during the early stage to grain yield. Mid-maturing varieties are recommended other than early maturing varieties for the SSEM areas even when late sowing occurs. Sowing as early as possible is recommended for areas with very short frost-free period (Harbin, Tongliao, and Datong). Proper delayed sowing is recommended for areas with a relative long frost-free period (Gongzhuling, Baicheng and Zhangjiakou). This research will provide a conducive reference for sorghum production in similar areas.

19.
Zhonghua Yi Xue Za Zhi ; 91(26): 1843-6, 2011 Jul 12.
Artigo em Chinês | MEDLINE | ID: mdl-22093788

RESUMO

OBJECTIVE: To explore the functions of TH17 cell in cutaneous graft-versus-host disease (GVHD). METHODS: A model of acute GVHD (aGVHD) was established with a major histocompatibility complex class I/II-disparate allogeneic bone marrow transplantation (BMT). Bone marrow monocytes and splenic T cells from donor C57/BL6 were enriched. The recipient BABL mice were irradiated ((60)Co source) with 7.5 Gy total body irradiation (TBI) and injected with 5 × 10(6) marrow monocytes and 5 × 10(5) T cells. The experimental mice were divided into 3 groups: lethal total body irradiation (TBI); allogeneic bone marrow transplantation (BMT) and recipients of halofuginone (HF). The symptoms of aGVHD were observed daily and detailed histopathologic analyses of recipient skin were performed at Day 6 post-transplantation. And Tri-color flow cytometry (FCM) was performed at Day 6 post-transplantation to measure the levels of interleukin (IL)-17, interferon (IFN)-γ and TH1/TH17. RESULTS: Clinical GVHD symptoms were observed in recipient mice. The administration of HF to lethally irradiated recipients led to very modest GVHD-induced cutaneous changes manifested predominantly by fur loss. However, the experimental animals receiving only allogeneic BMT showed significant fur loss and pathologic skin conditions. Consistent with the clinical evaluations, the histopathologic results demonstrated significantly increased pathologic cutaneous lesions in recipients undergoing only BMT. The median ratios of TH1/TH17 cells were 17.57 and 5.31 in the HF and BMT groups respectively. The difference had statistical significance (P < 0.05). The serum levels of IL-17 were(1.47 ± 0.18) and (2.81 ± 0.19) pg/ml in the TBI and BMT groups respectively (P < 0.05). But IL-17 could not be detected in the HF group. The serum levels of IFN-γ were (3.86 ± 0.32), (42.97 ± 0.42) and (9.89 ± 0.51) pg/ml in the TBI, BMT and HF groups respectively. The inter-group differences had statistical significance (P < 0.05). CONCLUSION: An absence of TH17 cell may alleviate the cutaneous GVHD but exacerbate the systemic GVHD.


Assuntos
Doença Enxerto-Hospedeiro/imunologia , Dermatopatias/imunologia , Células Th17/imunologia , Animais , Transplante de Medula Óssea/efeitos adversos , Doença Enxerto-Hospedeiro/etiologia , Interferon gama/sangue , Interleucina-17/sangue , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Dermatopatias/etiologia , Transplante Homólogo
20.
ACS Omega ; 6(13): 8850-8861, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33842756

RESUMO

It is crucial to accurately evaluate the slagging characteristics of coal before industrial application. However, when evaluating the Xinjiang high-sodium low-rank coal (XJc) according to the properties of the ash prepared at 815 °C, the ashing temperature of the coal sample specified by Chinese standards, forecasting failures are frequent. To figure out the internal reason, the influence of ashing temperature on predicting slagging characteristics of XJc was investigated via an ashing test and thermodynamic equilibrium calculation. Experimental results show that when XJc is ashed at 815 °C, the ash yield apparently reduces compared to the case when ashed at 500 °C since numerous volatile components are released. The release of these components contributes to an obvious inhibition in the formation of the liquid phase in the residual ash, especially at temperatures below 1200 °C. Hence, reducing the ashing temperature is conducive to the acquirement of more real ash compositions of XJc and thereby to the accurate prediction of the slagging behaviors. By a comparison with reported experimental results, it is found that the liquid ratio-temperature curve calculated from the ash compositions of the ash prepared at 500 °C basically reflects the actual slagging tendency of XJc. According to the evolution of minerals with temperature, two slagging mechanisms, self-fusion of sodium-bearing salts and low-temperature eutectics, are confirmed. In addition, effects of antislagging measures of adding refractory oxides greatly differ among coal types due to the diversity in ash compositions.

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