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1.
ACS Omega ; 6(50): 34675-34686, 2021 Dec 21.
Article in English | MEDLINE | ID: mdl-34963951

ABSTRACT

As the increasing pressure to carbon peak and carbon neutral has brought carbon capture and storage (CCS) to the forefront as an emission mitigation tool, greater attention is being paid to the potential for injecting dry boiler flue gas (DBFG) into oil reservoirs. With the aim to directly inject DBFG with steam into heavy oil reservoirs, this study presents the results of a laboratory investigation of the effect of DBFG on the properties and composition of heavy oil by viscosity measurement, pressure-volume-temperature measurement, high-temperature and high-pressure experiment, and high-resolution mass spectrometry analysis. The results of the experiments show that adding 0.5 wt % particulate matter has no obvious influence on the viscosity of heavy oil. DBFG dissolved in heavy oil can reduce viscosity, increase the flow capability, and make the heavy oil volume swell. Heavy oil is oxidized with DBFG at 140 °C, which is mainly caused by the O2 in the DBFG, and the oxidation product is alcohol. The findings of the beneficial effect of DBFG on viscosity and swelling factor and the negligible negative effect of the small amount of nitrogen oxides, sulfides, and particulate matter in DBFG are very encouraging. It is expected that DBFG can be directly injected into heavy oil, not only for enhanced oil recovery (EOR) but also for reducing the emissions of greenhouse gases and pollutants, as well as for saving costs.

2.
J Biochem Mol Toxicol ; 35(11): e22893, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34414639

ABSTRACT

Diabetic foot ulcer (DFU) is biggest life threats globally and increases their severity increases health complications for health of patients. The present study was investigated to recover the wound healing activity of baicalin in STZ-induced DFU rats by evaluating biochemical and molecular markers. The experimental animals induced with diabetes and excision wounds were treated with different doses of baicalin (25, 50, and 100 mg/kg). The serum glucose level, body weight and food intake were measured. In addition, DFU rat groups showed decreased food intake and increased body weight. The tissue was subjected to biochemical evaluation, histopathology, quantitative polymerase chain reaction and Western blot analysis. Histopathology reports revealed that diabetic wound control (DWC) + baicalin (100 mg/kg) treated group showed more than 90% recovery with more epithelization and remarkably improved angiogenesis and infiltration of the inflammatory cells. In this study we also proved that upregulated the p-ERK, ERK, HSP27, and p-HSP27 protein expression and mRNA expression of Ang-1, VEGF-c, TGF-ß, Tie-2, and SMAD2/3 implicating the potential antidiabetic and wound healing property of baicalin. Thus, baicalin is a potential therapeutic candidate for a diabetic foot ulcer and chronic wounds treatment.


Subject(s)
Diabetic Foot/genetics , Flavonoids/pharmacology , Gene Expression Regulation/drug effects , RNA, Messenger/genetics , Receptor, TIE-2/genetics , Smad2 Protein/genetics , Smad3 Protein/genetics , Transforming Growth Factor beta/genetics , Vascular Endothelial Growth Factor C/genetics , Wound Healing/genetics , Animals , Biomarkers/metabolism , Blood Glucose/metabolism , Body Weight/drug effects , Feeding Behavior/drug effects , Male , Oxidative Stress/drug effects , Rats , Rats, Sprague-Dawley , Streptozocin
3.
Sensors (Basel) ; 19(13)2019 Jul 09.
Article in English | MEDLINE | ID: mdl-31324068

ABSTRACT

The Internet of Things (IoT) will feature pervasive sensing and control capabilities via the massive deployment of machine-type communication devices in order to greatly improve daily life. However, machine-type communications can be illegally used (e.g., by criminals or terrorists) which is difficult to monitor, and thus presents new security challenges. The information exchanged in machine-type communications is usually transmitted in short packets. Thus, this paper investigates a legitimate surveillance system via proactive eavesdropping at finite blocklength regime. Under the finite blocklength regime, we analyze the channel coding rate of the eavesdropping link and the suspicious link. We find that the legitimate monitor can still eavesdrop the information sent by the suspicious transmitter as the blocklength decreases, even when the eavesdropping is failed under the Shannon capacity regime. Moreover, we define a metric called the effective eavesdropping rate and study the monotonicity. From the analysis of monotonicity, the existence of a maximum effective eavesdropping rate for a moderate or even high signal-to-noise (SNR) is verified. Finally, numerical results are provided and discussed. In the simulation, we also find that the maximum effective eavesdropping rate slowly increases with the blocklength.

4.
BMC Geriatr ; 17(1): 74, 2017 03 22.
Article in English | MEDLINE | ID: mdl-28330442

ABSTRACT

BACKGROUND: The health-related quality of life (HRQoL) of the elderly population of Yi ethnic minority, which is the seventh largest nationality in China, has been rarely reported. This study was designed to explore the HRQoL of the elderly Yi ethnicity and association between their HRQOL and functional abilities. METHODS: A total of 291 Yi ethnic residents were randomly recruited from 12 rural counties in Yunnan province and divided into different age groups. Local residents in Yunnan province and the elderly from Hangzhou were enrolled as controls. The MOS 36-Item Short Form Health Survey (SF-36), activities of daily living (ADL), instrumental activities of daily living (IADL) scales were utilized to evaluate the HRQoL and functional ability. One-way ANOVA was used to statistically compare the ADL and IADL among different age groups. The influential variables on HRQOL were analyzed by multiple linear regression analysis. Pearson correlation analysis was used to analyze the association among HRQoL, ADL and IADL. RESULTS: The HRQoL of the elderly Yi minority was significantly lower than those of local residents in Yunnan province and the elderly counterparts in Hangzhou. The IADL ability of the elderly Yi minority was low, whereas they could perform most items of ADL. ADL, IADL, and education level were positively associated with HRQoL, whereas age, chronic diseases, and the frequency of medication use were negatively correlated with HRQoL. CONCLUSION: The HRQoL and functional capacity of the elderly Yi ethnic minority were lower compared with their counterparts in Yunnan province and Hangzhou. The low level of IADL indicated that the elderly Yi participants had a high risk of cognitive impairment. Much attention should be diverted to influential factors of the HRQoL.


Subject(s)
Activities of Daily Living/psychology , Ethnicity/psychology , Health Status , Quality of Life/psychology , Rural Population , Surveys and Questionnaires , Aged , Aged, 80 and over , China/ethnology , Chronic Disease , Cognition Disorders/diagnosis , Cognition Disorders/ethnology , Cognition Disorders/psychology , Female , Humans , Male , Middle Aged
5.
Opt Express ; 24(10): 10946-55, 2016 May 16.
Article in English | MEDLINE | ID: mdl-27409916

ABSTRACT

We investigate ultra-broadband wavelength converters based on cascaded second-harmonic generation and difference frequency generation using Bessel-chirped gratings (BCGs) in lithium niobate waveguides, and compare them to the ones using uniform grating and segmented grating, respectively. For the same length and power, the BCGs show broader bandwidth than the other two types of grating. The ripple of the matching response is very small as well. Analysis also shows that almost the same conversion bandwidth and maximum conversion efficiency with tolerant response flatness can be achieved when the manufacturing tolerance of the waveguide length is smaller than 0.1 cm.

6.
Neurotoxicology ; 27(6): 970-81, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17056119

ABSTRACT

The developing brain is highly sensitive to methylmercury (MeHg). Still, the initial changes in cell proliferation that may contribute to long-term MeHg effects are largely undefined. Our previous studies with growth factors indicate that acute alterations of the G1/S-phase transition can permanently affect cell numbers and organ size. Therefore, we determined whether an environmental toxicant could also impact brain development with rapid (6-7h) effects on DNA synthesis and cell cycle machinery in neuronal precursors. In vivo studies in newborn rat hippocampus and cerebellum, two regions of postnatal neurogenesis, were followed by in vitro analysis of two precursor models, cortical and cerebellar cells, focusing on the proteins that regulate the G1/S transition. In postnatal day 7 (P7) pups, a single subcutaneous injection of MeHg (3microg/g) acutely (7h) decreased DNA synthesis in the hippocampus by 40% and produced long-term (2 weeks) reductions in total cell number, estimated by DNA quantification. Surprisingly, cerebellar granule cells were resistant to MeHg effects in vivo at comparable tissue concentrations, suggesting region-specific differences in precursor populations. In vitro, MeHg altered proliferation and cell viability, with DNA synthesis selectively inhibited at an early timepoint (6h) corresponding to our in vivo observations. Considering that G1/S regulators are targets of exogenous signals, we used a well-defined cortical cell model to examine MeHg effects on relevant cyclin-dependent kinases (CDK) and CDK inhibitors. At 6h, MeHg decreased by 75% levels of cyclin E, a cell cycle regulator with roles in proliferation and apoptosis, without altering p57, p27, or CDK2 nor levels of activated caspase 3. In aggregate, our observations identify the G1/S transition as an early target of MeHg toxicity and raise the possibility that cyclin E degradation contributes to both decreased proliferation and eventual cell death.


Subject(s)
Brain , Cell Proliferation/drug effects , Cyclin E/metabolism , Gene Expression Regulation, Developmental/drug effects , Methylmercury Compounds/pharmacology , Neurons/drug effects , Analysis of Variance , Animals , Animals, Newborn , Blotting, Western/methods , Brain/cytology , Brain/embryology , Brain/growth & development , Bromodeoxyuridine/metabolism , Cell Count , Cell Cycle/drug effects , Cells, Cultured , Dose-Response Relationship, Drug , Embryo, Mammalian , Female , Methylmercury Compounds/metabolism , Neurons/cytology , Pregnancy , Rats , Rats, Sprague-Dawley , Thymidine/metabolism , Time Factors , Tritium/metabolism
7.
Dev Neurosci ; 26(2-4): 197-207, 2004.
Article in English | MEDLINE | ID: mdl-15711060

ABSTRACT

While extracellular signals play a major role in brain neurogenesis, little is known about the cell cycle machinery underlying mitogen stimulation of precursor proliferation. Current models suggest that the D cyclins function as primary sensors of extracellular mitogens. Here we define the mechanisms by which basic fibroblast growth factor (bFGF) stimulates cortical precursors, with particular attention to the responses of cell cycle promitogenic and antimitogenic regulators. bFGF produced a 4-fold increase in DNA synthesis and a 3-fold rise in bromodeoxyuridine labeling, suggesting that the factor promotes the G1/S transition. There was also a 3-fold increase in cyclin-dependent kinase 2 (CDK2) kinase activity, which is critical for S phase entry. CDK2 activation was apparently cyclin E dependent, since only its protein and mRNA levels were elevated at 24 h, whereas CDK2, p27KIP1 and p57KIP2 levels were unaltered. Late G1 phase CDK2/cyclin E activity depends on early G1 D cyclin function. Indeed, cyclin D1, but not cyclin D3, was upregulated selectively at 8 h after bFGF treatment, a time when cyclin E was unchanged. The sequential activation of cyclin D1 and cyclin E supports the idea that cyclin E gene transcription is regulated by cyclin-D/CDK4/6-mediated pRb phosphorylation and subsequent E2F transcription factor release. However, in addition to increased D1 cyclin, we unexpectedly detected a 75% reduction in p27KIP1 protein at 8 h, suggesting that both pro- and antimitogenic regulators are targets of extracellular mitogens during brain development.


Subject(s)
Cell Cycle Proteins/metabolism , Cerebral Cortex/metabolism , Cyclin D1/metabolism , Fibroblast Growth Factor 2/metabolism , Neurons/metabolism , Stem Cells/metabolism , Tumor Suppressor Proteins/metabolism , Animals , Bromodeoxyuridine , CDC2-CDC28 Kinases/drug effects , CDC2-CDC28 Kinases/genetics , CDC2-CDC28 Kinases/metabolism , Cell Cycle Proteins/pharmacology , Cell Differentiation/drug effects , Cell Differentiation/physiology , Cell Proliferation/drug effects , Cells, Cultured , Cerebral Cortex/cytology , Cerebral Cortex/embryology , Cyclin D1/drug effects , Cyclin E/drug effects , Cyclin E/genetics , Cyclin E/metabolism , Cyclin-Dependent Kinase 2 , Cyclin-Dependent Kinase Inhibitor p27 , DNA/biosynthesis , DNA/drug effects , Down-Regulation/drug effects , Down-Regulation/genetics , Fibroblast Growth Factor 2/pharmacology , Neurons/cytology , Neurons/drug effects , RNA, Messenger/drug effects , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Stem Cells/cytology , Stem Cells/drug effects , Up-Regulation/drug effects , Up-Regulation/physiology
8.
J Neurosci ; 22(5): 1583-91, 2002 Mar 01.
Article in English | MEDLINE | ID: mdl-11880488

ABSTRACT

Generation of distinct cell types and numbers in developing cerebral cortex is subject to regulation by extracellular factors that positively or negatively control precursor proliferation. Although signals stimulating proliferation are well described, factors halting cell cycle progression are less well defined. At the molecular level, production and association of cyclins, cyclin-dependent kinases (CDKs), and CDK inhibitors (CKIs) regulate cycle progression. We now report that the endogenous peptide, pituitary adenylate cyclase activating polypeptide (PACAP), negatively regulates the cell cycle by inhibiting p57Kip2-dependent CDK2 activity in embryonic cortex. Protein levels of CDK2 and members of the CIP/KIP family of CKIs (p27Kip1, p57Kip2) were detected in developing rat cortex from embryonic day 13.5 through postnatal day 2. With advancing development, CDK2 protein levels decreased, whereas CKI expression increased, suggesting that stimulatory and inhibitory cycle proteins control cell cycle exit. Using a well defined, nonsynchronized, 8 hr precursor culture, PACAP decreased the fraction of cells crossing the G1/S boundary, inhibiting DNA synthesis by 35%. CDK2 kinase activity was inhibited 75% by PACAP, whereas kinase protein and its regulatory cyclin E subunit were unaffected. Moreover, decreased kinase activity was accompanied by a twofold increase in levels of p57Kip2 protein, but not p21Cip1 or p27Kip1, suggesting that p57Kip2 mediates PACAP anti-mitogenic effects. Indeed, immunoprecipitation of CDK2 complex revealed increased p57Kip2 association with the kinase and concomitant reduction in free inhibitor after PACAP exposure, suggesting that p57Kip2 interactions directly regulate CDK2 activity. These observations establish a mechanism whereby anti-mitogenic signals actively induce cell cycle withdrawal in developing cortex.


Subject(s)
CDC2-CDC28 Kinases , Cyclin-Dependent Kinases/metabolism , Neuropeptides/metabolism , Nuclear Proteins/metabolism , Protein Serine-Threonine Kinases/metabolism , Signal Transduction/physiology , Stem Cells/metabolism , Animals , Cell Cycle/drug effects , Cell Cycle/physiology , Cell Cycle Proteins/biosynthesis , Cell Cycle Proteins/metabolism , Cell Lineage/drug effects , Cells, Cultured , Cerebral Cortex/cytology , Cerebral Cortex/embryology , Cerebral Cortex/metabolism , Cyclin E/metabolism , Cyclin-Dependent Kinase 2 , Cyclin-Dependent Kinase Inhibitor p27 , Cyclin-Dependent Kinase Inhibitor p57 , DNA/biosynthesis , Embryonic and Fetal Development/physiology , HeLa Cells , Humans , Immunoblotting , Macromolecular Substances , Mitosis/drug effects , Mitosis/physiology , Neuropeptides/pharmacology , Pituitary Adenylate Cyclase-Activating Polypeptide , Rats , Rats, Sprague-Dawley , Signal Transduction/drug effects , Stem Cells/cytology , Stem Cells/drug effects , Tumor Suppressor Proteins/metabolism
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