Biography:

In the past Li Wang has collaborated on articles with C.B. Alcock and Rong-yao Wang. One of their most recent publications is The preparation and genesis of molybdena-alumina and related catalyst systems. Which was published in journal Journal of Catalysis.

More information about Li Wang research including statistics on their citations can be found on their Copernicus Academic profile page.

Li Wang's Articles: (828)

The preparation and genesis of molybdena-alumina and related catalyst systems

AbstractMolybdena-, tungsta-, chromia-, and vanadia-alumina preparations were made using an equilibrium adsorption technique. The Na+ cation was also tested and other supports (titania, magnesia, and silica gel) were employed. The loading of the support was not very dependent on the solution concentration, but for anions was a strong inverse function of the pH. It is shown that this (and the opposite dependence for cations) reflected the isoelectric point of the support surface. Reflectance spectra of the wet, dried (150 °C), and calcined (500 °C) catalysts are reported for molybdena-alumina preparations made at several pH values. In agreement with our previously published Raman data, the catalyst prepared at pH = 8.6 yielded spectra of a monomeric tetrahedral species while those made at lower pH yielded spectra characteristic of octahedral (polymeric) molybdena. Thus, better defined catalysts could be prepared for further study. The data support a model for the ordinary raw catalyst made by incipient wetness from solutions of ammonium paramolybdate in which the surface of the support becomes populated with randomly distributed small clusters (or islands) of polymolybdate species.

A new fringe carrier method for the determination of displacement derivatives in hologram interferometry

AbstractHolographic carrier fringes are produced by rotation of the object beam prior to the second exposure when the object is deformed. It is shown that the local pitch of the carrier is a linear function of displacement derivatives. The local pitch may be directly measured with a microscope or a digitized TV system. The theoretical foundation as well as an experimental demonstration are given in this paper.

New electrochemical sensors for oxygen determination

AbstractOxygen sensors which can operate in wider oxygen pressure and temperature ranges than currently used stabilized zirconia-based oxygen sensors are described. Strontium fluoride-lanthanum fluoride solid solution electrolytes have higher conductivities than zirconia and, when dispersed with an oxide phase, can operate at lower temperatures and oxygen partial pressures than zirconia-based oxygen sensors. Other potential electrolyte materials for low oxygen partial pressure applications are some very stable perovskite oxides, which are pure oxide-ion conductors at lower oxygen partial pressures than stabilized zirconia. In high-temperature aggressive environments, the lifetime of zirconia-based oxygen sensors can be extended through the use of a non-isothermal sensor, in which the temperature of the reference electrode is reduced.

- Optical nonlinearity of ZnO composite nanoparticles with different interfacial chemical environments

Publisher SummaryThis chapter reports that under proper thermal treatment, surface modification of ZnO nanoparticles with surfactant molecules result in the formation of a new ZnO-surfactant composite nanoparticles. The large and fast optical nonlinearity below band-gap occurring in these new organic-inorganic composite nanoparticles were examined by Z-scan and pump-probe technique. The sign and magnitude of both the real and imaginary parts of the third-order optical nonlinearity χ(3) of these ZnO composite nanoparticles with different chemical environments were measured by a single-beam Z-scan technique using 790 nm, 85 fs duration laser pulse. The ultrafast nonlinear response time, measured by time resolved pump-probe technique at excitation wavelength of 647 nm, suggest that the optical nonlinearity below band-gap originate mainly from a rapid electronic polarization process or virtual process such as the optical-stark effect.

Comparative proteomic analysis of surface proteins of Trichinella spiralis muscle larvae and intestinal infective larvae

Highlights•Surface proteins of T. spiralis ML and IIL were analyzed.•Forty one proteins were common to both larvae, 62 biased ML and 113 biased IIL.•Proteins of nitrogen compound metabolic process were highly expressed in IIL.•qPCR results confirmed that 4 of 6 IIL genes selected were up-regulated.•These proteins might be invasion-related proteins and vaccine candidate antigens.

Fundamentals of Intrathoracic Impedance Monitoring in Heart Failure

The primary objective of the first-generation implantable cardiac pacemakers was to provide critical heart rate support, but these devices did not have any diagnostic capabilities. In the intervening decades, the number, type, and complexity of implantable devices has greatly expanded. Today, implantable devices not only provide heart rate support but they also provide protection from sudden cardiac death with implantable cardioverter defibrillators (ICDs) and reduce symptoms and increase survival with cardiac resynchronization therapy (CRT). Furthermore, information on physiologic variables has been collected in patients with implanted devices for the purpose of providing sophisticated closed-loop optimization of their pacing and defibrillation algorithms. Thoracic fluid status monitoring via intrathoracic impedance is the newest device-based diagnostic capability. For those patients with heart failure who are already targeted to receive an ICD or CRT with defibrillator implant, the ability to monitor fluid status can provide additional insight into the difficult problem of evaluating and managing these patients. This article reviews the basics of measuring intrathoracic impedance via OptiVol fluid status monitoring (Medtronic, Inc., Minneapolis, MN), as well as clinical results regarding the utility of evaluating OptiVol intrathoracic impedance data trends.

Coronary Artery DiseaseA US Claims-Based Analysis of Real-World Lipid-Lowering Treatment Patterns in Patients With High Cardiovascular Disease Risk or a Previous Coronary Event

The objective was to examine real-world treatment patterns of lipid-lowering therapies and their possible associated intolerance and/or ineffectiveness in patients with high cardiovascular disease (CVD) risk initiating statins and/or ezetimibe. Patients aged ≥18 years who initiated statins and/or ezetimibe from January 01, 2007, to June 30, 2011, were retrospectively identified from the IMS LifeLink PharMetrics Plus commercial claims database. Patients were further classified into 2 cohorts: (1) history of cardiovascular event (CVE) and (2) history of coronary heart disease risk equivalent (CHD RE). Patients had continuous health plan enrollment ≥1 year pre- and post-index date (statin and/or ezetimibe initiation date). Primary outcomes were index statin intensity, treatment modifications, possible associated statin/nonstatin intolerance and/or ineffectiveness issues (based on treatment modification), and time-to-treatment modifications. Analyses for each cohort were stratified by age group (<65 and ≥65 years). A total of 41,934 (history of CVE) and 170,344 patients (history of CHD RE) were included. On the index date, 8.8% to 25.1% of patients were initiated on high-intensity statin. Among patients aged <65, 79.2% and 48.8% of those with history of CVE and 78.6% and 47.3% of those with a history of CHD RE had ≥1 and 2 treatment modifications, respectively. Among all patients, 24.6% to 25.6% had possible statin intolerance and/or ineffectiveness issues after accounting for second treatment modification (if any). In conclusion, in patients with high CVD risk, index statin treatment modifications that imply possible statin intolerance and/or ineffectiveness were frequent; low use of high-intensity statins indicates unmet need in the management of hyperlipidemia and possible remaining unaccounted CVD residual risk.

ReportMutations in Myosin Light Chain Kinase Cause Familial Aortic Dissections

Mutations in smooth muscle cell (SMC)-specific isoforms of α-actin and β-myosin heavy chain, two major components of the SMC contractile unit, cause familial thoracic aortic aneurysms leading to acute aortic dissections (FTAAD). To investigate whether mutations in the kinase that controls SMC contractile function (myosin light chain kinase [MYLK]) cause FTAAD, we sequenced MYLK by using DNA from 193 affected probands from unrelated FTAAD families. One nonsense and four missense variants were identified in MYLK and were not present in matched controls. Two variants, p.R1480X (c.4438C>T) and p.S1759P (c.5275T>C), segregated with aortic dissections in two families with a maximum LOD score of 2.1, providing evidence of linkage of these rare variants to the disease (p = 0.0009). Both families demonstrated a similar phenotype characterized by presentation with an acute aortic dissection with little to no enlargement of the aorta. The p.R1480X mutation leads to a truncated protein lacking the kinase and calmodulin binding domains, and p.S1759P alters amino acids in the α-helix of the calmodulin binding sequence, which disrupts kinase binding to calmodulin and reduces kinase activity in vitro. Furthermore, mice with SMC-specific knockdown of Mylk demonstrate altered gene expression and pathology consistent with medial degeneration of the aorta. Thus, genetic and functional studies support the conclusion that heterozygous loss-of-function mutations in MYLK are associated with aortic dissections.

ReportA Genome-wide Association Study Reveals that Variants within the HLA Region Are Associated with Risk for Nonobstructive Azoospermia

A genome-wide association study of Han Chinese subjects was conducted to identify genetic susceptibility loci for nonobstructive azoospermia (NOA). In the discovery stage, 802 azoospermia cases and 1,863 controls were screened for genetic variants in the genome. Promising SNPs were subsequently confirmed in two independent sets of subjects: 818 azoospermia cases and 1,755 controls from northern China, and 606 azoospermia cases and 958 controls from central and southern China. We detected variants at human leukocyte antigen (HLA) regions that were independently associated with NOA (HLA-DRA, rs3129878, pcombine = 3.70 × 10−16, odds ratio [OR] = 1.37; C6orf10 and BTNL2, rs498422, pcombine = 2.43 × 10−12, OR = 1.42). These findings provide additional insight into the pathogenesis of NOA.

ArticleOtud7a Knockout Mice Recapitulate Many Neurological Features of 15q13.3 Microdeletion Syndrome

15q13.3 microdeletion syndrome is characterized by a wide spectrum of neurodevelopmental disorders, including developmental delay, intellectual disability, epilepsy, language impairment, abnormal behaviors, neuropsychiatric disorders, and hypotonia. This syndrome is caused by a deletion on chromosome 15q, which typically encompasses six genes. Here, through studies on OTU deubiquitinase 7A (Otud7a) knockout mice, we identify OTUD7A as a critical gene responsible for many of the cardinal phenotypes associated with 15q13.3 microdeletion syndrome. Otud7a-null mice show reduced body weight, developmental delay, abnormal electroencephalography patterns and seizures, reduced ultrasonic vocalizations, decreased grip strength, impaired motor learning/motor coordination, and reduced acoustic startle. We show that OTUD7A localizes to dendritic spines and that Otud7a-null mice have decreased dendritic spine density compared to their wild-type littermates. Furthermore, frequency of miniature excitatory postsynaptic currents (mEPSCs) is reduced in the frontal cortex of Otud7a-null mice, suggesting a role of Otud7a in regulation of dendritic spine density and glutamatergic synaptic transmission. Taken together, our results suggest decreased OTUD7A dosage as a major contributor to the neurodevelopmental phenotypes associated with 15q13.3 microdeletion syndrome, through the misregulation of dendritic spine density and activity.

Meeting paperAUGS paperEpisiotomy in the United States: has anything changed?

ObjectiveThe objective of the study was to describe episiotomy rates in the United States following recommended changes in clinical practice.Study DesignThe National Hospital Discharge Survey, a federal data set sampling inpatient hospitals, was used to obtain data based on International Classification of Diseases, Clinical Modification, 9th revision, diagnosis and procedure codes from 1979 to 2004. Age-adjusted rates of term, singleton, vertex, live-born spontaneous vaginal delivery, operative vaginal delivery, cesarean delivery, episiotomy, and anal sphincter laceration were calculated. Census data for 1990 for women 15-44 years of age was used for age adjustment. Regression analysis was used to evaluate trends in episiotomy.ResultsThe rate of episiotomy with all vaginal deliveries decreased from 60.9% in 1979 to 24.5% in 2004. Anal sphincter laceration with spontaneous vaginal delivery declined from 5% in 1979 to 3.5% in 2004. Rates of anal sphincter laceration with operative delivery increased from 7.7% in 1979 to 15.3% in 2004. The age-adjusted rate of operative vaginal delivery declined from 8.7 in 1979 to 4.6 in 2004, whereas cesarean delivery rates increased from 8.3 in 1979 to 17.2 per 1000 women in 2004.ConclusionRoutine episiotomy has declined since liberal usage has been discouraged. Anal sphincter laceration rates with spontaneous vaginal delivery have decreased, likely reflecting the decreased usage of episiotomy. The decline in operative vaginal delivery corresponds to a sharp increase in cesarean delivery, which may indicate that practitioners are favoring cesarean delivery for difficult births.

Original articleSize of Corneal Topographic Effective Optical Zone: Comparison of Standard and Customized Myopic Laser In Situ Keratomileusis

PurposeTo investigate the corneal topographic effective optical zone (EOZ) in eyes after wavefront-guided myopic laser in situ keratomileusis (LASIK) and to compare them with the EOZ after standard LASIK.DesignRetrospective, case-control study.MethodsWe evaluated the corneal topographic maps of 41 eyes of 25 consecutive patients who had CustomVue LASIK (CV LASIK) and 41 eyes of 23 patients who had standard LASIK with correction up to − 7 diopters using the VISX Star S4 laser (VISX Inc, Santa Clara, California, USA). On the refractive map of the Humphrey Topography System, we defined the EOZ as the area outlined by a change of corneal power of 0.5 diopters from the power at the center of the pupil. We analyzed the differences in EOZs of the two ablation patterns and the correlation between EOZ and magnitude of refractive correction.ResultsThe mean postoperative EOZs were 17.9 ± 3.7 mm2 and 11.4 ± 3.4 mm2 after CV and standard LASIK, representing 60% and 40% of the laser-programmed optical zones, respectively (both P < .0001). There was no correlation between the postoperative EOZs and the magnitude of refractive correction for both ablations (all P > .05). In eyes with spherical correction (cylinder ≤0.25 diopters), CV LASIK increased the preoperative EOZ by 3.8 ± 5.6 mm2 (P = .018), whereas standard LASIK decreased EOZ by 4.5 ± 5.2 mm2 (P = .005).ConclusionCV LASIK created larger corneal topographic EOZs than standard ablation. In eyes with spherical correction, the preoperative EOZ was expanded by CV LASIK and reduced by standard LASIK.

Regular articleGastrointestinal, hepatobiliary, and pancreatic pathologyREV-ERBα Activates C/EBP Homologous Protein to Control Small Heterodimer Partner–Mediated Oscillation of Alcoholic Fatty Liver

The small heterodimer partner (SHP) nuclear receptor is an important regulator of nonalcoholic fatty liver disease. However, little is known about the role of SHP in alcoholic fatty liver. In this study, we used a modified chronic ethanol–binge model to examine cyclic alterations of lipid metabolism in wild-type (WT) and Shp−/− mice over a 24-hour period after binge. The serum and hepatic lipid profiles, as well as the expression of lipid synthesis genes and markers of endoplasmic reticulum stress, exhibited distinct variations in WT and Shp−/− mice in response to ethanol diet plus ethanol binge (ED+E) and control diet plus maltose binge. ED+E induced steatosis in WT mice, which correlated with a marked up-regulation of activating transcription factor 4 protein (ATF4) but down-regulation of C/EBP homologous protein (CHOP) and sterol regulatory element-binding transcription factor 1c protein (SREBP-1c). On the contrary, the control diet plus maltose binge caused lipid accumulation in Shp−/− mice, which was accompanied by a sharp elevation of CHOP, SREBP-1c, and REV-ERBα proteins but a diminished ATF4. REV-ERBα activated CHOP promoter activity and gene transcription, which were inhibited by SHP. Knockdown Rev-Erbα in Shp−/− mice prevented steatosis induced by ED+E. Our study revealed a critical role of SHP and REV-ERBα in controlling rhythmic CHOP expression in alcoholic fatty liver.

Clinical InvestigationAssociation Between Aldehyde Dehydrogenase 2 Glu504Lys Polymorphism and Alcoholic Liver Disease☆★

AbstractBackgroundOnly a subset of patients with excessive alcohol use develop alcoholic liver disease (ALD), though the exact mechanism is not completely understood. Once ingested, alcohol is metabolized by 2 key oxidative enzymes, alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH). There are 2 major ALDH isoforms, cytosolic and mitochondrial, encoded by the aldehyde ALDH1 and ALDH2 genes, respectively. The ALDH2 gene was hypothesized to alter genetic susceptibility to alcohol dependence and alcohol-induced liver diseases. The aim of this study is to determine the association between aldehyde dehydrogenase 2 (rs671) glu504lys polymorphism and ALD.MethodsALDH2 genotyping was performed in 535 healthy controls and 281 patients with ALD.ResultsThe prevalence of the common form of the single nucleotide polymorphism rs671, 504glu (glu/glu) was significantly higher in patients with ALD (95.4%) compared to that of controls (73.7%, P < 0.0001). Among controls, 23.7% had the heterozygous (glu/lys) genotype compared to 4.6% in those with ALD (odds ratio [OR] = 0.16, 95% CI: 0.09-0.28). The allele frequency for 504lys allele in patients with ALD was 2.3%, compared to 14.5% in healthy controls (OR = 0.13, 95% CI: 0.07-0.24).ConclusionsPatients with ALDH2 504lys variant were less associated with ALD compared to those with ALDH2 504glu using both genotypic and allelic analyses.

Voltammetric determination of butylated hydroxyanisole, butylated hydroxytoluene, propyl gallate and tert-butylhydroquinone by use of chemometric approaches

AbstractThe voltammetric behavior of synthetic food antioxidants, such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), propyl gallate (PG) and tert-butylhydroquinone (TBHQ), at a glassy carbon electrode in solution of 0.1 mol l−1 perchloric acid containing 1% methanol has been investigated. The obtained linear sweep voltammograms (LSV) showed that all these four compounds have well-defined oxidation waves with peak potentials of 629, 818, 599 and 501 mV for BHA, BHT, PG and TBHQ, respectively. Linear calibration graphs were also obtained in the concentration ranges of 0.5–15.0, 0.5–8.0, 1.0–15.0 and 1.0–15.0 mg l−1 for BHA, BHT, PG and TBHQ, respectively. However, the voltammetric peaks of these antioxidants seriously overlap and it is difficult to determine them individually from a mixture without prior separation. In this work, a method for simultaneous determination of these antioxidants, based on their oxidation at the glassy carbon electrode, with the aid of chemometric approaches, such as classical least squares (CLS), principal component regression (PCR) and partial least squares (PLS), has been developed. The method was applied to determine the four antioxidants in a set of synthetic mixtures and several commercial food samples; in general, satisfactory results were obtained.

High sensitivity analysis of water-soluble, cyanine dye labeled proteins by high-performance liquid chromatography with fluorescence detection

AbstractA water-soluble sulfo-3H-indocyanine dye, the active N-hydroxysuccinimide ester of 3H-Indolium,1-[(4-carboxyphenyl)methyl]-2-[3-[1-[(4-carboxyphenyl)methyl]-1,3-dihydro-3,3-dimethyl-5-sulfo-2H-indol-2-ylidene]-1-propenyl]-3,3-dimethyl-5-sulfo-(9CI) (sb-cy3-NHS), containing two p-carboxybenzyl groups on nitrogen atoms, previously developed by our laboratory, was for the first time used for protein derivatization, followed by HPLC separation and fluorescence detection. With bovine serum albumin (BSA) as a model protein, effects of various experimental conditions, including denaturant concentration, reaction time and temperature, the pH value of buffer, and the molar ratio of fluorescence reagent to protein, on protein derivatization efficiency were systematically investigated. Under the optimal conditions, the limit of detection (LOD) for derivatized BSA was decreased to 12.8 nM, about 100-fold lower than that by UV and fluorescence detection with commercial fluorescein isothiocyanate (FITC) as labeling reagent. For HPLC analysis, an on-column excess fluorescence reagent depletion technique was developed based on the hydrophilicity of sb-cy3-NHS, which could avoid the interference on the analysis of target compounds. In addition, sb-cy3-NHS was applied for the derivatization of a three-protein mixture and egg white proteins. Compared to the results labeled by FITC, more proteins with low concentrations could be labeled by sb-cy3-NHS, resulting in improved detection sensitivity for protein analysis. All these results demonstrated that sb-cy3-NHS might be promising in detecting low abundance proteins, especially in the quantitative analysis of proteins.

ReviewReview on synthesis of ferrocene-based redox polymers and derivatives and their application in glucose sensing

Highlights•Synthesis and analytical performance of ferrocene as redox mediators were discussed.•Key features are their stability and excellent redox properties.•Applications of ferrocene-based polymers in other biosensors were briefly mentioned.•Challenges in this field and future trend were discussed.

Coupling a universal DNA circuit with graphene sheets/polyaniline/AuNPs nanocomposites for the detection of BCR/ABL fusion gene

Highlights•A transducer hairpin was designed to improve the versatility of DNA circuit.•GS/PANI/AuNPs were introduced to the DNA circuit for further signal amplification.•The established biosensor displayed high sensitivity and good specificity.

An in vitro approach for lipolysis measurement using high-resolution mass spectrometry and partial least squares based analysis

Highlights•A novel approach for lipolysis measurement combining UHPLC-Orbitrap and partial least squares (PLS) was developed.•28 FFAs were accurately screened out from medium samples to build PLS model.•A SUS Plot was introduced for intuitively comparison of two OPLS-DA models.•O2PLS model was used for joint analysis of FFAs and lipidome.

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