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Fine and dispersed Mg–Ti–oxide inclusions, which act as heterogeneous nucleation sites for intragranular ferrite, have been acknowledged as an effective method for grain refinement. In this paper, the nucleation and growth mechanisms of ferrite on Mg–Ti-oxides surface were investigated through first-principles calculations and solid-state pressure bonding experiments. The calculated results show that the formation of cation vacancies is the limiting step for Mn solute atom absorption by Mg–Ti-oxides. As determined by the lower covalency and ionicity of the Mg–O bond compared to the Ti–O bond in Mg–Ti-oxides, Mn atoms will be efficiently absorbed by occupying the Mg vacancies. The experimental results demonstrate that MgTiO3 with the maximum Mn-depleted zone (MDZ) width is the most effective for ferrite nucleation, which is consistent with the calculation results. As a representative, the Fe(110)/MgTiO3(001) interface with the lowest planar disregistry (3.16%) was selected to analyze growth behaviors. Due to charge accumulation and variation, Fe atoms are more likely to gather on the Mg–O terminal MgTiO3(001) surface and form [(Mg–O)–Fe]-1 interfaces. Its adhesion work and interface energy are 1.74 and 2.46 J/m2, respectively. The present study illustrates the nucleation and growth mechanisms of ferrite on Mg–Ti-oxides, providing theoretical support for the application of Mg–Ti-oxide inclusions in oxide metallurgy.

Abstract Background Although maternal deaths are rare in developed regions, the morbidity associated with severe postpartum hemorrhage (SPPH) remains a major problem. To determine the prevalence and risk factors of SPPH, we analyzed data of women who gave birth in Guangzhou Medical Centre for Critical Pregnant Women, which received a large quantity of critically ill obstetric patients who were transferred from other hospitals in Southern China. Methods In this study, we conducted a retrospective case-control study to determine the prevalence and risk factors for SPPH among a cohort of women who gave birth after 28 weeks of gestation between January 2015 and August 2019. SPPH was defined as an estimated blood loss ≥1000 mL and total blood transfusion≥4 units. Logistic regression analysis was used to identify independent risk factors for SPPH. Results SPPH was observed in 532 mothers (1.56%) among the total population of 34,178 mothers. Placenta-related problems (55.83%) were the major identified causes of SPPH, while uterine atony without associated retention of placental tissues accounted for 38.91%. The risk factors for SPPH were maternal age

The distribution of pharmatically important alkaloids gelsemine, koumine, and gelsenicine in Gelsemium elegans tissues is a hot topic attracting research attention. Regretfully, the in planta visual distribution details of these alkaloids are far from clear although several researches reported the alkaloid quantification in G. elegans by LC-MS/MS. In this study, mass imaging spectrometry (MSI) was employed to visualize the in situ visualization of gelsemine, koumine, and gelsenicine in different organs and tissues of G. elegans at different growth stages, and the relative quantification of three alkaloids were performed according to the image brightness intensities captured by the desorption electrospray ionization MSI (DESI-MSI). The results indicated that these alkaloids were mainly accumulated in pith region and gradually decreased from pith to epidermis. Interestingly, three alkaloids were found to be present in higher abundance in the leaf vein. Along with the growth and development, the accumulation of these alkaloids was gradually increased in root and stem. Moreover, we employed LC-MS/MS to quantify three alkaloids and further validated the in situ distributions. The content of koumine reached 249.2 μg/g in mature roots, 272.0 μg/g in mature leaves, and 149.1 μg/g in mature stems, respectively, which is significantly higher than that of gelsemine and gelsenicine in the same organ. This study provided an accurately in situ visualization of gelsemine, koumine, and gelsenicine in G. elegans, and would be helpful for understanding their accumulation in plant and guiding application.

Objective To investigate the outcome on 90 d and influencing factors for the outcome in conscious patients with intracerebral hemorrhage (ICH). Methods Two hundred and twenty-five patients with ICH were admitted to our hospital within 6 h after onset and were suitable to be treated with medical conservative therapy. Patients were divided into two groups, the conscious group [Glasgow Coma Scale (GCS) score ≥ 9] and the coma group (GCS score ≤ 8). Clinical features including gender, age, National Institute of Health Stroke Scale (NIHSS) score, etc, were recorded. The prognosis of these patients on 90 d after onset was evaluated by the following index: survival or death; favorable prognosis [modified Rankin Scale (mRS) score ≤ 2] or unfavorable prognosis (mRS score ≥ 3, death or severe disability). The difference of clinical features and prognosis between the conscious group and coma group was explored. The prognosis of the patients in conscious group was analyzed, and influencing factors for prognosis were explored. Results Multifactorial Logistic regression analysis indicated that hyperglycemia, higher NIHSS score, rehemorrhagia and hematemesis were independent risk factors for 90-day mortality. On the other hand, advanced age, higher NIHSS score, rehemorrhagia and hematemesis were independent risk factors for death or severe disability on 90-day. Conclusion In ICH patients who were conscious on admission, hyperglycemia, advanced age, higher NIHSS score, rehemorrhagia and hematemesis are strong predictors for mortality and unfavourable outcome. Controlling hyperglycemia and prevention of rehemorrhagia and hematemesis are important elements for reducing 90-day mortality and severe disability.

The optimal regulation properties of multi-input and multioutput (MIMO) discrete-time networked control systems (NCSs), over additive white Gaussian noise (AWGN) fading channels, based on state space representation, are investigated. The average performance index is introduced. Moreover, the regulation performance is measured by the control energy and the error energy of the system, and fundamental limitations are obtained. Two kinds of network parameters, fading and the additive white Gaussian noise, are considered. The best attainable regulation performance limitations can be obtained by the limiting steady state solution of the corresponding algebraic Riccati equation (ARE). The simulation results are given to demonstrate the main results of the theoretical development.

Some plant growth-promoting rhizobacteria (PGPR) regulated plant growth and elicited plant basal immunity by volatiles. The response mechanism to the Bacillus amyloliquefaciens volatiles in plant has not been well studied. We conducted global gene expression profiling in Arabidopsis after treatment with Bacillus amyloliquefaciens FZB42 volatiles by Illumina Digital Gene Expression (DGE) profiling of different growth stages (seedling and mature) and tissues (leaves and roots). Compared with the control, 1,507 and 820 differentially expressed genes (DEGs) were identified in leaves and roots at the seedling stage, respectively, while 1,512 and 367 DEGs were identified in leaves and roots at the mature stage. Seventeen genes with different regulatory patterns were validated using quantitative RT-PCR. Numerous DEGs were enriched for plant hormones, cell wall modifications, and protection against stress situations, which suggests that volatiles have effects on plant growth and immunity. Moreover, analyzes of transcriptome difference in tissues and growth stage using DGE profiling showed that the plant response might be tissue-specific and/or growth stage-specific. Thus, genes encoding flavonoid biosynthesis were downregulated in leaves and upregulated in roots, thereby indicating tissue-specific responses to volatiles. Genes related to photosynthesis were downregulated at the seedling stage and upregulated at the mature stage, respectively, thereby suggesting growth period-specific responses. In addition, the emission of bacterial volatiles significantly induced killing of cells of other organism pathway with up-regulated genes in leaves and the other three pathways (defense response to nematode, cell morphogenesis involved in differentiation and trichoblast differentiation) with up-regulated genes were significantly enriched in roots. Interestingly, some important alterations in the expression of growth-related genes, metabolic pathways, defense response to biotic stress and hormone-related genes were firstly founded response to FZB42 volatiles.

The variations of microstructure and mechanical properties of a high-chromium cast iron for rolls were studied from as-cast to the final heat treatments. Results show that the as-cast microstructure of the HCCI consists of M7C3 carbide, M23C6 carbide, martensite matrix, and retained austenite. The large dendritic M7C3 carbide surrounds the matrix, and the M23C6 carbide is mainly distributed in the matrix. Part of M23C6 carbide transforms to M7C3 carbide and is dissolved in austenite during austenization at 1020°C. Thus, the amount of M23C6 carbide decreases, whereas that of M7C3 carbide increases after quenching; the highest hardness is also obtained. After tempering, the martensite transforms to a tempered martensite, and some carbide precipitates in the martensite matrix. The hardness also changes from HRC62.1, which corresponds to quenching, to HRC55.2 and HRC56.3, which correspond to once and twice tempering, respectively. However, tempering could improve the impact toughness and wear resistance of the HCCI.

We propose an energy-aware dynamic routing strategy in order to provide balanced energy consumption in wireless sensor networks, hence, prolonging the lifetime of the network. The proposed routing algorithm uses local betweenness centrality to estimate the energy consumption of the neighboring nodes around a given local sensor node, without requiring global information about the network topology or energy consumption, and to divert traffic from nodes that are more heavily used. Because nodes with large local betweenness centrality consume energy more quickly, the network lifetime can be prolonged by redistributing energy consumption to nodes with smaller local betweenness centrality. Simulation results showed that the proposed routing strategy has advantages over shortest path routing with respect to extending network lifetime and balancing energy consumption in wireless sensor networks, yet does not introduce significant additional transmission overhead or a longer average path length.

This paper deals with the distributed consensus of the multiagent system. In particular, we consider the case where the velocity (second state) is unmeasurable and the communication among agents occurs at sampling instants. Based on the impulsive control theory, we propose an impulsive consensus algorithm that extends some of our previous work to account for the lack of velocity measurement. By using the stability theory of the impulsive system, some necessary and sufficient conditions are obtained to ensure the consensus of the controlled multiagent system. It is shown that the control gains, the sampled period and the eigenvalues of Laplacian matrix of communication graph play key roles in achieving consensus. Finally, a numerical simulation is provided to illustrate the effectiveness of the proposed algorithm.

Objective: To understand the status of human hookworm ( Ancylostoma duodenale or Necator americanus ) infection in Jiangxi Province., Methods: A stratified cluster random sampling was conducted based on the geographical location and economic condition in 2014. Kato-Katz's thick smear method was used for stool examinations, and filter paper cultivation was conducted for distinguishing the species of hookworms., Results: A total of 21 615 persons were involved in the investigation, and there were 1 095 persons infected with hookworm with the prevalence of 5.07% (standardized rate of 4.05%). The infection rate of hookworm in Nanfeng County was the highest (13.96%). Most of the infected people had low worm burden (95.43%). The infection rate of hookworm of the female was higher than that of the male ( χ 2 = 28.03, P < 0.05). The prevalence increased with the age, while the infection rate of hookworm in people at ages of 75 years and higher was the highest (14.79%). Housewife was the highest risk occupation with the infection rate of 7.55%. The differences of infection rates among different educational level groups were significant ( χ 2 = 135.88, P < 0.05). The prevalence rates of hookworm in different landforms were significantly different ( χ 2 = 34.37, P < 0.05). The priority species was N. americanus (80.41%) in Jiangxi Province., Conclusions: The infection rate of hookworm decreases obviously in Jiangxi Province. The high risk groups of hookworm infection are the people with low educational level, female and elder age-group.

Objective: To discuss the clinical features of cerebral schistosomiasis., Methods: The clinical data of fourteen patients with cerebral schistosomiasis from March 2010 to March 2016 were collected and analyzed retrospectively., Results: The schistosomiasis immunological tests of sera and cerebrospinal fluids from the fourteen patients were all positive. Eosinophils increased in ten cases, and the proportion was 5.1%-60.3%. Schistosoma eggs were found in seven cases by the fecal Kato-Katz method. Fourteen cases were all infected with Schistosome japonicum . Twelve cases were diagnosed as chronic type, and two cases as acute type. Thirteen patients received medical treatment, of which twelve were cured, and one improved. One patient received the surgical resection of the lesion., Conclusions: The clinical manifestations of cerebral schistosomiasis mainly include seizure, headache, dizziness and fever. In the enhanced head magnetic resonance imaging (MRI), the lesions are clustered and merged into lumps, which is the characteristic image of cerebral schistosomiasis japonica. The praziquantel treatment can achieve a good prognosis.