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Taraxacum kok‐saghyz Rodin (TKS) has abundant natural rubber in its root and the molecular weight of its natural rubber is higher than that in Hevea brasiliensis. Thus, TKS is an excellent alternative for the commercial production of natural rubber. The content and molecular weight of natural rubber are two qualitative indicators. Efficient determination for both indicators is still a challenge. In this study, we developed a method to simultaneously determine the content and molecular weight of natural rubber in TKS with pyrolysis－gas chromatography‐mass spectrometry. The content of natural rubber was quantified by internal standard method. We optimized the pyrolysis temperature and chromatographic method during content determination. The limits of detection and quantification were 0.47 and 1.56 μg, respectively. In addition, the arachidonic acid methyl ester, an unsaturated fatty acid proposed from the α‐end group of natural rubber, was quantified to obtain the number of natural rubber polymers. Based on the content and the polymer number, we also quantified the molecular weight of natural rubber. Thus, the content and molecular weight of natural rubber were simultaneously determined in TKS. Our study provides a new perspective for the high throughput analysis of natural rubber. [ABSTRACT FROM AUTHOR]

Shape memory polymers (SMP) and its composites (SMPC) have gained popularity for their potential in intelligent structures fields. Developing a reliable mechanical model to accurately describe mechanical behavior of its intelligent structures is important for both theory and practice. This paper presents a novel mechanical model for describing the mechanical behavior of short glass fiber/polyurethane (GF/PU) composite beams, based on a constitutive model of SMP and incorporating principles from composite mechanics theory, the Hamiltonian principle and Euler–Bernoulli beam theory. The model includes kinematic equations and material parameter equations. Based on the constitutive equations of SMP, coupled with Euler–Bernoulli beam theory and Hamilton's principle, the kinematic equations of GF/PU composite beam are established. Additionally, a correction factor was proposed and employed to modify the material parameter equation of SMP, which was then combined with the mechanics theory of composite materials to establish a material parameter equation for composite beams. Taking a simply supported beam as an example, we solve the model using Fourier method and simulate and analyze the material parameters properties, static and viscous mechanical behaviors properties, and shape memory behavior properties of the GF/PU composite beam. The results show that the GF volume fraction, temperature correction coefficient, regularization parameter, and contact parameter have a significant impact on the material parameters of GF/PU composite materials and the material parameters of composite beams have important effects on their mechanical properties. By adjusting material parameters, ideal mechanical properties can be obtained for the GF/PU composite beam. This study provides a theoretical foundation for intelligent beam design and analysis based on SMP and SMPC. Highlights: A novel viscoelastic mechanical model for GF/PU composite beam is proposed.Effect of composite components on GF/PU composite is studied.Kinematic equations based on Hamiltonian principle is established.Material parameter equation including corrected parameter is established. [ABSTRACT FROM AUTHOR]

SUMMARY: Fruit size and shape are controlled by genes expressed during the early developmental stages of fruit. Although the function of ASYMMETRIC LEAVES 2 (AS2) in promoting leaf adaxial cell fates has been well characterized in Arabidopsis thaliana, the molecular mechanisms conferring freshy fruit development as a spatial–temporal expression gene in tomato pericarp remain unclear. In the present study, we verified the transcription of SlAS2 and SlAS2L, two homologs of AS2, in the pericarp during early fruit development. Disruption of SlAS2 or SlAS2L caused a significant decrease in pericarp thickness as a result of a reduction in the number of pericarp cell layers and cell area, leading to smaller tomato fruit size, which revealed their critical roles in tomato fruit development. In addition, leaves and stamens exhibited severe morphological defects in slas2 and slas2l single mutants, as well as in the double mutants. These results demonstrated the redundant and pleiotropic functions of SlAS2 and SlAS2L in tomato fruit development. Yeast two‐hybrid and split‐luciferase complementation assays showed that both SlAS2 and SlAS2L physically interact with SlAS1. Molecular analyses further indicated that SlAS2 and SlAS2L regulate various downstream genes in leaf and fruit development, and that some genes participating in the regulation of cell division and cell differentiation in the tomato pericarp are affected by these genes. Our findings demonstrate that SlAS2 and SlAS2L are vital transcription factors required for tomato fruit development. Significance Statement: Understanding early fruit development in tomato is critical since the size and shape of a fruit is largely decided in the early stages. Our previous work identified hundreds of transcription factors specifically expressed in the pericarp of 0–5 days post anthesis fruits in tomato that are likely involved in this complex process. ASYMMETRIC LEAVES 2 (AS2) belongs to the LATERAL ORGAN BOUNDARIES family, and its role in promoting leaf adaxial cell fates in Arabidopsis has been well characterized. SlAS2 and SlAS2L, two homologs of AS2 in tomato, are specifically expressed in the ovary wall/pericarp at early fruit developmental stage, but their functions in fleshy fruit development are still unclear. In the present study, we found that knockout mutations in SlAS2 or SlAS2L caused significantly reduced pericarp thickness, leading to smaller mature fruit size. Histocytological observation of the pericarp revealed that disruption of SlAS2 or SlAS2L inhibited both cell division and expansion, leading to the observed thinner pericarp. Additionally, leaf and stamen defects in single and double mutants suggested that SlAS2 and SlAS2L have redundant functions in plant development. Both SlAS2 and SlAS2L interact with SlAS1 in vitro, which is consistent with Arabidopsis AS2. Molecular analyses revealed that genes regulated by SlAS2 and SlAS2L in leaf and fruit development are different, and were related to cell division and differentiation processes during tomato pericarp development. Our results confirm the vital roles of SlAS2 and SlAS2L in regulating tomato fruit development. [ABSTRACT FROM AUTHOR]

Summary: This study focuses on the problems of safety control and stabilization for time‐varying nonlinear systems in the presence of time‐varying full‐state constraints. High‐order control barrier functions (HoCBFs) without the assumption of forward completeness are introduced to prevent high‐relative degree constraint violations. The activated HoCBFs, which determine the dynamic sub‐safe sets, are proposed to indicate that the state constraints are already or about to be violated. Subsequently, the HoCBFs‐based controller is designed to obtain the admissible control set by utilizing the quadratic programming (QP) with activated HoCBFs conditions to synthesize the nominal controller. An explicit analytical expression is provided for the HoCBFs‐based controller. The input‐to‐state stable (ISS) property of the closed‐loop system under the proposed controller is investigated to ensure that all closed‐loop states remain bounded and achieve asymptotic tracking without violation of the constraint. Moreover, a Lyapunov‐like constraint is added to the HoCBFs‐based QP problem such that the solvability of the QP problem is a sufficient condition for the system ISS. The effectiveness of the proposed HoCBFs‐based control method for time‐varying nonlinear systems is illustrated using a numerical example. [ABSTRACT FROM AUTHOR]

Sanjiangyuan National Park (SNP), the first national park in China, is one of the most important biodiversity conservation areas in the Sanjiangyuan National Nature Reserve (SNNR) and even the world. The threatened ungulates play an irreplaceable role in maintaining the ecosystem diversity and stability in SNNR. Here, based on 1434 occurrence records of six ungulates, the maximum entropy model, with two different strategies, was utilized to determine the priority reserves. The results indicated that the priority reserves in SNNR was mainly located in and around SNP, which were mainly distributed in the middle east, middle west, and southwest of SNNR. Six ungulates shared preference for altitude ranging 4000–5000 m, the average annual temperature below −3.0°C, and average annual precipitation ranging 200–400 mm on meadow, steppe, and unused land. The proportion of high and medium suitable areas for ungulates in SNP was higher than that in SNNR. As the SNP is not contiguously spaced in space, and some core wildlife habitats are not included, it is suggested to optimize the functional areas and adjust the boundary range on the basis of the pilot scope of SNP, so as to enhance the integrity and connectivity of each functional area. [ABSTRACT FROM AUTHOR]

Recent studies have shown that MDR could be induced by the high stemness of cancer cells. In a previous study, we found bufalin could reverse MDR and inhibit cancer cell stemness in colorectal cancer, but the relationship between them was unclear. Here we identified overexpressing CD133 increases levels of Akt/nuclear factor‐κB signaling mediators and MDR1, while increasing cell chemoresistance. Furthermore, bufalin reverses colorectal cancer MDR by regulating cancer cell stemness through the CD133/nuclear factor‐κB/MDR1 pathway in vitro and in vivo. Taken together, our results suggest that bufalin could be developed as a novel 2‐pronged drug that targets CD133 and MDR1 to eradicate MDR cells and could ultimately be combined with conventional chemotherapeutic agents to improve treatment outcomes for patients with colorectal cancer. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the effect of a decrease in blood pressure (BP) fulfilling the diagnostic criteria for orthostatic hypotension (OH) on performance in each domain of cognitive function in patients with type 2 diabetes mellitus using a cross-sectional and within-group design.Methods: Subjects were individuals without dementia and with type 2 diabetes mellitus, including 107 individuals without OH and 94 with OH (DMOH); 95 control participants were also included. BP was assessed in both the supine and standing positions. A detailed neuropsychological assessment was made in each posture for all subjects.Results: There were statistically significant differences between the patients without OH and the DMOH group with regard to some cognitive measures while supine. Standing posture exacerbated and broadened cognitive deficits in the DMOH group for all measures in the different domains of cognition including executive functioning, memory, visuospatial skills, information processing speed, and attention. When group-specific supine scores were used as baseline anchors, both the patients without OH and the DMOH group showed cognitive changes when transitioning from a supine to a standing, upright position, with the DMOH group exhibiting a wider range of neuropsychological deficits in memory, visuospatial skills, executive function, and sustained attention, as well as significant changes in information processing speed.Interpretation: These data demonstrate that type 2 diabetes mellitus patients with OH had transient, posture-mediated cognitive deficits in excess of those found in diabetes mellitus without OH. Understanding the effects of OH on cognition due to autonomic failure is important, particularly as clinical assessments and neuroimaging collect data only in the seated or supine positions. ANN NEUROL 2019;86:754-761. [ABSTRACT FROM AUTHOR]

Abstract: Oxidative stress can cause injury in retinal endothelial cells. Carboxymethyl cellulose modified with collagen peptide (CMCC) is of a distinct antioxidant capacity and potentially a good drug carrier. In this study, the protective effects of CMCC against H2O2‐induced injury of primary retinal endothelial cells were investigated. In vitro, we demonstrated that CMCC significantly promoted viability of H2O2‐treated cells, efficiently restrained cellular reactive oxygen species (ROS) production and cell apoptosis. Then, the CMCC was employed as both drug and anti‐inflammatory drug carrier for treatment of retinal ischaemia/reperfusion (I/R) in rats. Animals were treated with CMCC or interleukin‐10‐loaded CMCC (IL‐10@CMCC), respectively. In comparisons, the IL‐10@CMCC treatment exhibited superior therapeutic effects, including better restoration of retinal structural thickness and less retinal apoptosis. Also, chemiluminescence demonstrated that transplantation of IL‐10@CMCC markedly reduced the retinal oxidative stress level compared with CMCC alone and potently recovered the activities of typical antioxidant enzymes, SOD and CAT. Therefore, it could be concluded that CMCC provides a promising platform to enhance the drug‐based therapy for I/R‐related retinal injury. [ABSTRACT FROM AUTHOR]

Epithelial ovarian cancer (EOC) is one of the most prevalent gynaecological cancers. Euxanthone, an active ingredient of the medicinal plant Polygala caudata, exhibits a selective cytotoxic effect in tumour cells. The present study was aimed to determine whether euxanthone could suppress ovarian tumour growth, and to study the relevant mechanism. Two EOC cell lines, SKOV3 and A2780, were used as the in vitro model and treated with euxanthone. Cell viability and apoptosis were assayed using Cell Counting Kit‐8 (CCK‐8) and Annexin‐V FITC/PI staining, respectively. Commercially available kits were used to measure the glucose consumption, lactate production, and intracellular ATP levels. Western blots assay was conducted to examine the level of apoptotic markers. To examine the roles of HK2 and STAT3 in the anti‐tumour effect of euxanthone, cells were transfected with vectors overexpressing HK2 or STAT3, and assayed as above. Finally, SKOV3 cells were injected to mice models to appreciate the anti‐neoplastic effect of euxanthone in vivo. We found that euxanthone impaired the cell viability and induced apoptosis via the intrinsic pathway in a concentration‐dependent fashion in both SKOV3 and A2780 cells. Euxanthone also caused inhibition of glycolysis. Apoptosis and glycolysis inhibition was mediated by the downregulation of HK2, which in turn was a result of STAT3 inactivation. In vivo experiments also supported that euxanthone could exert anti‐cancer activities without general toxicity. In conclusion, euxanthone triggered mitochondrial apoptosis and inhibited glycolysis in EOC cells. Significance of the study: Euxanthone triggered mitochondrial apoptosis and inhibited glycolysis in EOC cells. Our findings provide preliminary experimental data that support further studies on the potential therapeutic role of euxanthone in ovarian cancer. [ABSTRACT FROM AUTHOR]

The present study investigated 15 dead cases of captive wild goslings ( Anser anser), which were bred in a small poultry farm in Shandong Province, China. The examined cases presented diverse clinical signs accompanied with neurological manifestations and fatal outcomes. Bacterial culture identified the gram-negative Neisseria sp. from the brain homogenate of most examined cases (10/15, 66.7%). The isolated bacteria were identified based on morphologic characteristics, biochemical tests and 16S rDNA typing. Results proved that 1 identical bacterial strain (BNO09-3) was isolated from the positive cases. The phylogeny based on the 16S rDNA gene sequences indicated that this isolate has a close relationship with various strains of genus Neisseria sp. isolated from liver and feces of duck. This is the first report of Neisseria sp. causing fatality in captive wild geese in China. [ABSTRACT FROM AUTHOR]

Irrigation of agricultural oases is the main water consumer in semi-arid and arid regions of Northwestern China. The accurate estimation of evapotranspiration (ET) on the oases is extremely important for evaluating water use efficiency so as to reasonably allocate water resources, particularly in semi-arid and arid areas. In this study, we integrated the soil moisture information into surface energy balance system (SEBS) for improving irrigated crop water consumption estimation. The new approach fed with the moderate resolution imaging spectro-radiometer images mapped spatiotemporal ET on the oasis in the middle reach of the Heihe river. The daily ET outputs of the new approach were compared with those of the original SEBS using the eddy correlation observations, and the results demonstrate that the modified SEBS remedied the shortcoming of general overestimating ET without regard to soil water stress. Meanwhile, the crop planting structure and leaf area index spatiotemporal distribution in the studied region were derived from the high-resolution Chinese satellite HJ-1/CCD images for helping analyse the pattern of the monthly ET (ETmonthly). The results show that the spatiotemporal variation of ETmonthly is closely related to artificial irrigation and crop growth. Further evaluation of current irrigation water use efficiency was conducted on both irrigation district scale and the whole middle reach of the Heihe river. The results reveal that the average fraction of consumed water on irrigation district scale is 57% in 2012. The current irrigation water system is irrational because only 52% of the total irrigated amount was used to fulfil plant ET requirement and the rest of the irrigation water recharged into groundwater in the oasis in 2012. However, in view of the whole middle reach of the Heihe river, the irrigation water use efficiency could reach to 66% in 2012. But pumping groundwater for reused irrigation wastes mostly energy instead of water. An improved irrigation water allocation system according to actual ET requirement is needed to increase irrigation efficiency per cubic meter water resource in an effort to save both water and energy. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background The study aimed to assess the prevalence and causes of corneal blindness in a rural northern Chinese population. Design Cross-sectional study. Participants or Samples The cluster random sampling method was used to select the sample. Methods This population-based study included 11 787 participants of all ages in rural Heilongjiang Province, China. These participants underwent a detailed interview and eye examination that included the measurement of visual acuity, slit-lamp biomicroscopy and direct ophthalmoscopy. An eye was considered to have corneal blindness if the visual acuity was <9/18 because of corneal diseases. Main Outcome Measures The main outcome measure was prevalence rates of corneal blindness and low vision. Results Among the 10 384 people enrolled in the study, the prevalence of corneal blindness is 0.3% (95% confidence interval 0.2-0.4%). The leading cause was keratitis in childhood (40.0%), followed by ocular trauma (33.3%) and keratitis in adulthood (20.0%). Age and illiteracy were found to be associated with an increased prevalence of corneal blindness. Conclusion Blindness because of corneal diseases in rural areas of Northern China is a significant public health problem that needs to be given more attention. [ABSTRACT FROM AUTHOR]

A bstract Background: The prevalence of blind individuals in the north of China is unknown. The study aimed to investigate the prevalence and causes of blindness and low vision in rural areas in Heilongjiang province of China in 2008-2009. Design: Cross-sectional study. Participants or Samples: A cluster random sampling method was used to recruit participants of all ages in rural areas of Heilongjiang. Methods: Trained professionals performed interviews and clinical examinations to measure visual acuity. The relationships between blindness or low vision and age, gender and education level were analysed. Main Outcome Measures: The main outcome measure was prevalence rates of bilateral blindness and bilateral low vision. Results: Of the 11 787 subjects, 10 384 (88.1%) were surveyed. The overall age-adjusted prevalence rates were 0.7% (95% confidence interval: 0.5-0.8%) for bilateral blindness and 1.7% (95% confidence interval: 1.4-1.9%) for bilateral low vision. The prevalence rates of blindness and low vision were higher in the elderly and uneducated population ( P < 0.05). The main causes for blindness and low vision were cataracts (44.1 and 46.0%, respectively) and refractive errors (17.7 and 42.5%, respectively). Conclusion: Blindness and low vision are highly prevalent among people with cataracts and refractive errors. Eye care planning must focus on treating the avoidable and curable forms of blindness. [ABSTRACT FROM AUTHOR]

The Xianbei existed as a remarkable nomadic tribe in northeastern China for three dynasties: the Han, Jin, and Northern-Southern dynasties (206 BC to 581 AD) in Chinese history. A very important subtribe of the Xianbei is the Murong Xianbei. To investigate the genetic structure of the Murong Xianbei population and to address its genetic relationships with other nomadic tribes at a molecular level, we analyzed the control region sequences and coding-region single nucleotide polymorphism markers of mtDNA from the remains of the Lamadong cemetery of the Three-Yan Culture of the Murong Xianbei population, which is dated to 1,600-1,700 years ago. By combining polymorphisms of the control region with those from the code region, we assigned 17 individuals to haplogroups B, C, D, F, G2a, Z, M, and J1b1. The frequencies of these haplogroups were compared with those of Asian populations and a multidimensional scaling graph was constructed to investigate relationships with other Asian populations. The results indicate that the genetic structure of the Lamadong population is very intricate; it has haplogroups prevalent in both the Eastern Asian and the Siberian populations, showing more affinity with the Eastern Asian populations. The present study also shows that the ancient nomadic tribes of Huns, Tuoba Xianbei, and Murong Xianbei have different maternal genetic structures and that there could have been some genetic exchange among them., ((c) 2007 Wiley-Liss, Inc.)