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1.
Langmuir ; 39(17): 6151-6159, 2023 May 02.
Article in English | MEDLINE | ID: mdl-37076449

ABSTRACT

Human-machine interactions, medical monitoring, and flexible robots stimulate interest in hydrogel sensing devices. However, developing hydrogel sensors with multifunctions such as good mechanics, electroconductivity, resistance to solvent volatility as well as freezing, self-adhesion, and independence on external power supply remains a challenge. In the work, a poly(acrylic acid-N-isopropylacrylamide) P(AA-NIPAm) organic hydrogel loading LiCl is prepared by ultraviolet cross-linking in ethylene glycol/H2O. The organic hydrogel exhibits favorable mechanical properties such as an elongation of break at 700% and a breaking strength of 20 KPa, can adhere to various substrates, and resists frost and solvent volatility. Especially, it possesses an excellent conductivity of 8.51 S/m. The organic hydrogel shows wide strain sensitivity based on resistance change, and the gauge factor reaches 5.84 in the range of 300-700%. It has short responsive and recuperative time and is still stable within 1000 rounds. Moreover, the organic hydrogel is also assembled into a self-powered device in which the open-circuit voltage is 0.74 V. The device can transform external stimuli such as stretching or compressing into the output current change, so it detects human motion effectively in real time. The work provides a perspective for electrical sensing engineering.

2.
Article in English | MEDLINE | ID: mdl-36361371

ABSTRACT

Environmental investment of companies can not only bring profits to firms but also contribute to environmental protection. However, little is known about how chairperson characteristics affect companies' decisions on environmental investment. This paper fills the gap in the literature by studying the impact of chairperson characteristics on firms' environmental investment. For empirical evidence, we conduct a regression on environmental protection disclosure data of Chinese listed companies sourced from the CSMAR database. We find that China's overall environmental protection disclosure level is relatively low. The age of the chairperson has an inverted U-shaped relationship with environmental investment, and a female chairperson has a significant positive effect on environmental investment. Contrarily, the education level and political connections of the chairperson have no significant impact on firms' environmental investment. Understanding the effect of these factors will help companies plan their environmental protection activities more efficiently.


Subject(s)
Conservation of Natural Resources , Investments , Female , Humans , Disclosure , Databases, Factual , China
3.
Article in English | MEDLINE | ID: mdl-36612893

ABSTRACT

This study examines the effect of commuting time on quality of life. We find that the longer the commute time workers use, the lower satisfaction with work and life they have; the long commute also causes health damage, affecting physical health and causing inactivity. However, better public transportation infrastructure can decrease commuting time, especially the construction of subways.


Subject(s)
Quality of Life , Transportation , Humans , Sedentary Behavior , China , Walking , Bicycling
4.
J Biomater Sci Polym Ed ; 31(4): 456-471, 2020 03.
Article in English | MEDLINE | ID: mdl-31801405

ABSTRACT

Synergistic delivery of two drugs is a desirable choice to overcome drug resistance. Resveratrol (RES) and xanthohumol (XAN) which are both new drugs originated from plants exhibit great potential in the treatment of cancer, but there are few studies on combining them in a delivery system. In this work, a new core/shell fiber mesh containing RES and XAN was designed out via coaxial electrospinning, and the effect of drug content on the medicated fibers was discovered. RES/polyethylene oxide (PEO) could be well combined with XAN/Poly(lactide-glycolide) (PLGA) to make core/shell fibers, but fibrous morphology worsened with increasing drug content of the core or shell to some extent. The core/shell was amorphous nature, and changing drug content had little influence on the wetability of the core/shell fibers. The release accelerated with drug content increasing in the fibers, and RES and XAN showed gradient release, which the release rate of RES was slower than XAN. These two drugs could sustain release for 350 h. When the blend ratios of RES/PEO and XAN/PLGA were 50/50 and 10/90 in the fibers, the fiber mesh showed the best mechanical properties, of which the tensile strength and elongation at break were 2.85 ± 0.10 MPa and 55.23 ± 2.53%, respectively. The medicated fibers presented good characteristics of inhibiting breast cancer cell activity.


Subject(s)
Drug Delivery Systems/methods , Electricity , Flavonoids/administration & dosage , Propiophenones/administration & dosage , Resveratrol/administration & dosage , Cell Line, Tumor , Delayed-Action Preparations , Drug Delivery Systems/instrumentation , Humans , Materials Testing , Polyethylene Glycols/chemistry , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Tensile Strength , Wettability
5.
Insect Biochem Mol Biol ; 105: 33-42, 2019 02.
Article in English | MEDLINE | ID: mdl-30602123

ABSTRACT

Endoparasitoid wasps deliver a variety of maternal factors, such as venom proteins, viruses, and virus-like particles, from their venom and calyx fluid into hosts and thereby regulate the hosts' immune response, metabolism and development. The endoparasitoid, Microplitis mediator, is used as an important biological agent for controlling the devastating pest Helicoverpa armigera. In this study, using an integrated transcriptomic and proteomic analysis approach, we identified 75 putative venom proteins in M. mediator. The identified venom components were consistent with other known parasitoid wasps' venom proteins, including metalloproteases, serine protease inhibitors, and glycoside hydrolase family 18 enzymes. The metalloprotease and serpin family showed extensive gene duplications in venom apparatus. Isobaric tags for relative and absolute quantitation (iTRAQ) based quantitative proteomics revealed 521 proteins that were differentially expressed at 6 h and 24 h post-parasitism, including 10 wasp venom proteins that were released into the host hemolymph. Further analysis indicated that 511 differentially expressed proteins (DEP) from the host are primarily involved in the immune response, material metabolism, and extracellular matrix receptor interaction. Taken together, our results on parasitoid wasp venoms have the potential to enhance the application of endoparasitoid wasps for controlling insect pest.


Subject(s)
Host-Parasite Interactions , Insect Proteins/metabolism , Moths/parasitology , Wasp Venoms/metabolism , Wasps/metabolism , Animals , Female
6.
RSC Adv ; 9(21): 11901-11911, 2019 Apr 12.
Article in English | MEDLINE | ID: mdl-35516997

ABSTRACT

Poly(procaterol hydrochloride) (p-ProH) polymeric film was successfully deposited onto the carboxyl multi-walled carbon nanotube (CMWCNT) modified glass carbon electrode (GCE) to construct a p-ProH/CMWCNT composite modified GCE. Due to the synergistic effect of p-ProH and CMWCNT in the composite, the developed sensor can enormously enhance the oxidation peak current of bromhexine hydrochloride (BrH) at ca. + 0.90 V. Based on this appearance, an electrochemical method was established for the sensitive and selective determination of BrH with differential pulse voltammetry (DPV). Various conditions affecting the peak current response of BrH were studied and optimized. Under the best conditions, the oxidation peak current of BrH is linear to its concentration in two linear dynamic ranges of 0.2-1.0 µmol L-1 (R = 0.9948) and 1.0-8.0 µmol L-1 (R = 0.9956), with a detection limit of 0.1 µmol L-1 (S/N = 3). Interference experiment indicated that the as-prepared electrochemical sensor showed wonderful selectivity to the recognition of BrH and was free from disturbance of many other electro-active substances such as dopamine, ascorbic and uric acid. Finally, the practicability of the BrH sensor was verified by the satisfactory results acquired from the BrH determination in pharmaceutical preparation and human serum.

7.
Talanta ; 174: 436-443, 2017 Nov 01.
Article in English | MEDLINE | ID: mdl-28738604

ABSTRACT

Poly(glutamic acid) (P-GLU)/carboxyl functionalized multiwalled carbon nanotubes (MWCNTs-COOH)/polyvinyl alcohol (PVA) modified glassy carbon electrode (GCE) has been successfully prepared and the electrochemical behavior of procaterol hydrochloride (ProH) was studied. The results show that the as-prepared modified electrode exhibits a good electrocatalytic property towards the oxidation of ProH in 0.2M phosphate buffer solution (PBS) (pH 6.0) due to the enhanced oxidation peak current at ~+0.59V. Under optimal reaction conditions, the oxidation peak current of ProH is proportional to its concentration in the linear dynamic ranges of 0.060 - 8.0µM (R = 0.9974), with a detection limit of 8.0 × 10-9M. Finally, this method was efficiently used for the determination of ProH in tablets and human urine with recoveries of 88.5~98.7% and 89.2 ~ 108.0%, respectively.


Subject(s)
Electrochemistry/instrumentation , Glass/chemistry , Glutamic Acid/chemistry , Nanotubes, Carbon/chemistry , Polyglutamic Acid/chemistry , Polyvinyl Alcohol/chemistry , Procaterol/analysis , Electrodes , Humans , Models, Molecular , Molecular Conformation , Polymerization , Procaterol/urine
8.
J Invertebr Pathol ; 130: 88-96, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26183795

ABSTRACT

The ichneumonid wasp, Campoletis chlorideae Uchida, successfully develops in the cotton bollworm Helicoverpa armigera (Hübner), but rarely survives in the beet armyworm Spodoptera exigua (Hübner) due to the encapsulation by host immunity. In this study, we investigated the role of C. chlorideae ichnovirus (CcIV) and eggs in the evasion of the host immune system. Washed eggs of different types, immature, mature, newly laid, or pretreated with protease K, were injected alone or with the calyx fluid containing CcIV into the larvae of H. armigera and S. exigua. In H. armigera, when injected with washed eggs alone, only 9.5% of the mature eggs were encapsulated at 24h post-injection. This is much lower than that of the immature eggs (100%), mature eggs pretreated with protease K (100%) and newly laid eggs (54.4%). No encapsulation was observed when the washed eggs were co-injected with calyx fluid at 24h post-injection. Conversely, the eggs in all treatments were encapsulated in S. exigua. Electron microscopic observations of parasitoid eggs showed structural differences between the surfaces of the mature and other kinds of eggs. The injected CcIV decreased the numbers of host hemocytes and suppressed the spreading ability of plasmatocytes and granulocytes in H. armigera, but had little effect on the hemocytes from S. exigua. In conclusion, the C. chlorideae egg provides a passive protection against encapsulation by itself, and CcIV supplies an active protection through disrupting host immune responses. These coordinated protections are host-specific, implying their role in host range determination.


Subject(s)
Host-Parasite Interactions/immunology , Moths/parasitology , Polydnaviridae/immunology , Spodoptera/parasitology , Wasps/virology , Animals , Eggs , Immune Tolerance/immunology , Larva
9.
J Theor Biol ; 358: 85-92, 2014 Oct 07.
Article in English | MEDLINE | ID: mdl-24954019

ABSTRACT

The haplotype assembly problem has been proven to be complex. Heuristic algorithms are the main methods that are used to solve the problem. These algorithms perform well when the SNP fragments are error-free, but they are less accurate when the error rate increases. The complex relationships caused by fragment errors present a major barrier to assembling accurate haplotypes. Therefore, modeling the complex relationships is the key to solve the problem. In this study, we model the haplotype assembly problem using hypergraph partitioning formulations and propose a novel method termed HGHap (Hypergraph-based Haplotype assembly method). HGHap approaches the haplotype assembly problem in two phases. In the first phase, a hypergraph is constructed in which each vertex corresponds to a fragment and vertices are multiply connected to form hyperedges. In the second phase, a hypergraph partitioning algorithm is employed to obtain two groups of fragments to construct the haplotypes. The hyperedges capture higher-order relationships among fragments that facilitate the subsequent partitioning. Our results demonstrate that the method performs better than other methods in most cases, especially in cases with a high error rate.


Subject(s)
Algorithms , Haplotypes , Human Genome Project , Humans
10.
ISRN Gastroenterol ; 2014: 913890, 2014.
Article in English | MEDLINE | ID: mdl-24616815

ABSTRACT

This study aimed to evaluate factors associated with significant liver histological changes. Liver biopsies from 157 CHB patients were retrospectively analyzed. Only ALB was significantly correlated with advanced liver necroinflammatory (P = 0.001). Age, ALB, GLOB, AST, PLT, and PT were independent predictors of significant fibrosis (P = 0.002, P < 0.001, P = 0.001, P = 0.048, P < 0.001, and P = 0.001, resp.). AST, WBC, and HBV DNA were significantly correlated with advanced fibrosis in normal ALT patients (P < 0.001, P = 0.041, and P = 0.012, resp.) and age, ALB, GLOB, PLT, and PT in patients with abnormal ALT (P = 0.003, P < 0.001, P = 0.004, P < 0.001, and P = 0.002, resp.). Age, AST, GGT, PLT, and PT were significantly associated with advanced fibrosis in HBeAg+ patients (P = 0.01, P = 0.016, P = 0.027, P = 0.016, and P = 0.009, resp.) and ALB, GLOB, WBC, PLT, and PT in HBeAg- patients (P < 0.001, P = 0.004, P = 0.005, P < 0.001, and P = 0.035, resp.). PLT was an excellent predictor for cirrhosis (P < 0.001 and AUROC = 0.805). ALT was not predictive of advanced fibrosis for patients with HBeAg+ or HBeAg- (P = 0.273 and P = 0.599, resp.). PLT was an excellent predictor for cirrhosis in CHB patients. Liver histopathology can be recommended for chronic HBV carriers of older age, with normal ALT, lower PLT, and lower ALB.

11.
IEEE Trans Syst Man Cybern B Cybern ; 42(3): 603-15, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22106151

ABSTRACT

Deadlock-free control and scheduling are vital for optimizing the performance of automated manufacturing systems (AMSs) with shared resources and route flexibility. Based on the Petri net models of AMSs, this paper embeds the optimal deadlock avoidance policy into the genetic algorithm and develops a novel deadlock-free genetic scheduling algorithm for AMSs. A possible solution of the scheduling problem is coded as a chromosome representation that is a permutation with repetition of parts. By using the one-step look-ahead method in the optimal deadlock control policy, the feasibility of a chromosome is checked, and infeasible chromosomes are amended into feasible ones, which can be easily decoded into a feasible deadlock-free schedule. The chromosome representation and polynomial complexity of checking and amending procedures together support the cooperative aspect of genetic search for scheduling problems strongly.


Subject(s)
Algorithms , Decision Support Techniques , Industry/methods , Models, Theoretical , Neural Networks, Computer , Pattern Recognition, Automated/methods , Robotics/methods , Computer Simulation , Models, Genetic
12.
Zhonghua Gan Zang Bing Za Zhi ; 19(6): 431-5, 2011 Jun.
Article in Chinese | MEDLINE | ID: mdl-22053373

ABSTRACT

OBJECTIVE: To investigate the relevant factors of liver histological changes in chronic hepatitis B (CHB) patients with mildly elevated ALT and to explore the clinical values of these factors on anti-viral treatment. METHODS: A total of 152 CHB patients with mildly elevated ALT (less than 2 x ULN) who underwent liver biopsy were included in the study. Correlations between routine laboratory markers, liver histological inflammation grade and fibrosis stage were statistically assessed by Spearman correlation analysis, one-way ANOVA, area under the curve (AUC) of the receiver operating characteristic curves (ROC) and Logistic regression statistical analysis. RESULTS: All patients in the study showed various hepatic histological damages. Among the 152 patients 50 (32.9%) were found with inflammation grade 1 (G1), 42 (27.6%) with G2, 46 (30.3%) with G3 and 14 (9.2%) with G4. 16 patients (10.5%) were found with fibrosis stage 2 (S2), 25 (16.5%) with S3 and 41 (27.0%) with S4. Routine laboratory markers Alb, BPC and WBC were significantly correlated with hepatic histological inflammation grade and fibrosis stage. Marked liver fibrosis and moderate to severe liver damage were significantly higher in patients aged more than 40 years as compared to those less than 40 years of age (P = 0.002, P = 0.010). The regression equation P = 1/[1+e-(9.36250-1625Alb-0.0234BPC)] was established with sensitivity and specificity of 83.3% and 65.0%, respectively. CONCLUSION: 67.8% of CHB patients with mildly elevated ALT have significant injury to the liver tissue. CHB patients aged more than 40 years have a significant increase of marked liver fibrosis and moderate to severe liver damage. The regression equation is valuable to predict whether CHB patients need antiviral therapy or not.


Subject(s)
Alanine Transaminase/metabolism , Hepatitis B, Chronic/metabolism , Hepatitis B, Chronic/pathology , Adolescent , Adult , Female , Hepatitis B, Chronic/enzymology , Humans , Liver/pathology , Liver Cirrhosis/pathology , Male , Middle Aged , Young Adult
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