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- Author or Editor: Huang Wei x
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Abstract
We obtained data of statistical significance to verify the intuitive impression that collaboration leads to higher impact. We selected eight scientific journals to analyze the correlations between the number of citations and the number of coauthors. For different journals, the single-authored articles always contained the lowest citations. The citations to those articles with fewer than five coauthors are lower than the average citations of the journal. We also provided a simple measurement to the value of authorship with regards to the increase number of citations. Compared to the citation distribution, similar but smaller fluctuations appeared in the coauthor distribution. Around 70% of the citations were accumulated in 30% of the papers, while 60% of the coauthors appeared in 40% of the papers. We find that predicting the citation number from the coauthor number can be more reliable than predicting the coauthor number from the citation number. For both citation distribution and coauthor distribution, the standard deviation is larger than the average value. We caution the use of such an unrepresentative average value. The average value can be biased significantly by extreme minority, and might not reflect the majority.
Abstract
This study employs the method of direct citation to analyze and compare the interdisciplinary characteristics of the two disciplines of library science and information science during the period of 1978–2007. Based on the research generated by five library science journals and five information science journals, library science researchers tend to cite publications from library and information science (LIS), education, business/management, sociology, and psychology, while researchers of information science tend to cite more publications from LIS, general science, computer science, technology, and medicine. This means that the disciplines with larger contributions to library science are almost entirely different from those contributing to information science. In addition, researchers of library science frequently cite publications from LIS; the rate is as high as 65.61%, which is much higher than the rate for information science, 49.50%. However, a decreasing trend in the percentage of LIS in library science indicates that library science researchers tend to cite more publications from non-LIS disciplines. A rising trend in the proportion of references to education sources is reported for library science articles, while a rising trend in the proportion of references to computer science sources has been found for information science articles. In addition, this study applies an interdisciplinary indicator, Brillouin's Index, to measurement of the degree of interdisciplinarity. The results confirm that the trend toward interdisciplinarity in both information science and library science has risen over the years, although the degree of interdisciplinarity in information science is higher than that in library science.
Summary
In order to explore the interaction between the expression of ZnT3 (Zinc Transporter 3) mRNA (Messenger Ribonucleic Acid) and the concentration of elemental zinc in mouse brain, zinc distribution in brain was determined by synchrotron radiation X-ray fluorescence (SRXRF) technique and a ZnT3 mRNA expression in tissue was examined by the reverse-transcriptase polymerase chain reaction (RT-PCR) method.The results show that the zinc concentration is not evenly distributed in brain slices. Its concentrations in cerebral cortex and hippocampus are nearly 5-10 times higher than those in other positions. A corresponding relation is that ZnT3 mRNA in cerebral cortex, hippocampus and testis has higher abundant degree, but it is not examined out in other tissues. Furthermore, the results promote that ZnT3 facilitates the accumulation of zinc in synaptic vesicles and may play an important role in structuring of vesicular zinc pool.
Abstract
Polyether-urethane samples were irradiated at the dose range from 10 to 2000 kGy by 2 MeV electron beams. Volatile species from the polymer degradation were analyzed quantitatively and qualitatively with GC/MS. Thermal properties and micro-phase separation of the samples were examined by TG and the morphology was studied by TEM and SEM. The results show that the irradiated polyether-polyurethane evolves CO2, H2, CH4 and C2H6, etc. The thermal stabilities between the hard and soft segments in the irradiated samples are different. At high doses, the phase separation in the sample is predominant and the hard segment of sample is more stable. The dose rate affects the soft segment of the irradiated sample much more.
Abstract
Flower-like ammonium cadmium phosphate monohydrate was synthesized by solid-state reaction at low temperature and characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscope, and elemental analysis. The product NH4CdPO4·H2O was obtained with flower-like morphology by the addition of fatty alcohol-polyoxyethylene ether surface-active agent. Based on Hess's law, thermochemical cycle was designed to determine the dissolution enthalpies of reactants and products using a solution-reaction isoperibol calorimeter at 298.15 K, and the molar reaction enthalpy was calculated on the basis of above dissolution enthalpies. With the aid of other auxiliary thermodynamic data, the standard molar formation enthalpy of the title compounds was concluded: 
Abstract
In this work, elemental distributions in the rat olfactory bulbs (OB) were measured by synchrotron radiation X-ray fluorescence (SRXRF) 9 hours after unilateral intranaris application of MnCl2 solution. The effects of deposition of exogenous Mn in the OB on the distributions of other elements, particularly calcium, were also investigated. The results show that the application of MnCl2 solution in the nasal cavity resulted in inhomogeneous deposition of Mn in the OB, with the highest Mn content found in the ipsilateral glomerular layer (GL). Locations in the ipsilateral hemisphere of the OB with higher Mn content were found to be associated with significantly higher calcium and zinc contents, suggesting the presence of excess exogenous Mn may affect the homeostasis of other trace elements such as calcium and zinc.
The most abundant seed storage proteins of wheat are gliadins and glutenins. Gliadins, including α/β, γ and ω types, are normally monomeric proteins and account for about 50% of the gluten proteins. In this study, 55 sequences of γ -gliadin genes were obtained from species of Sitopsis section, the deduced B genome donors of wheat. Despite the high sequence similarities to the known γ -gliadin genes, extensive variations were also found. Using the extensive sequence information deposited in database and obtained in this study, a comprehensive classification of the γ -gliadin multigene families were performed based on the primary structures and phylogenic analysis. All the γ -gliadin genes analyzed could be divided into 2 types, which contain 8 and 9 cysteines, respectively. Type I (with 8 cysteines) and type II (with 9 cysteines) are further classified to 7 and 4 groups, respectively, and several subgroups are also identified. The genes derived from A, B and D genomes of common wheat were clustered distinctly, indicating that there was apparent genomic specificity in γ -gliadins genes. Besides the high homology between γ -gliadin genes from Sitopsis species and B genome of wheat, some unique groups or subgroups were also identified in Sitopsis section, suggesting that it could be considered as a valuable source of γ -gliadin genes. The comparison of deduced primary structures of each group and/or subgroup was conducted, from which their evolution and quality properties were also speculated.
A residue analytical method was developed for the determination of trichlorfon, chlorpyrifos, dimethoate, β cypermethrin, deltamethrin, and chlorothalonilin in six leafy vegetables by gas chromatography–electron capture detector (GC–ECD) and gas chromatography–flame photometric detector (GC–FPD). The method had a good linearity (R 2 ≥ 0.9924) and precision (RSD ≤ 14.0%). The limits of quantification (LOQ) of six pesticides were all 0.01 mg/kg. Average recoveries of six pesticides ranged from 81% to 119%. The developed method was successfully applied to study the initial deposits, degrade characteristics, and terminal residues for six pesticides applied to six leafy vegetables under the same dose of formulation. The half-life of six pesticides was in the range of 0.8–8.8 days. The highest initial deposits, maximal residues, and terminal residues were found on leaf mustard and sweet potato leaves as the same pesticides were applied in different crops. Therefore, leaf mustard can be selected as representative commodity in the same subgroup to realize the residual extrapolation. This conclusion should be considered as a complement on crop classification of China.
Abstract
Ganoderma lucidum (GL), also known as Reishi or Lingzhi, is a medicinal mushroom widely used in traditional and folk medicines. The extracts made from the fruiting body and spore of naturally grown GL are the most frequently used in commercial products. More than 400 compounds have been identified in GL with the triterpenoids considered to be the major active components. Large variations in the chemical components were reported in previous studies and there is no comprehensive study of the content of multiple major triterpenoids in the GL product. In addition, there is no report in the comparison of chemical profiles in different parts of GL (i.e., fruiting body and spore). Determining the chemical composition and comparing the differences between fruiting body and spore are essential for the identity, efficacy and safety of various GL products.
In this study, 13 compounds (ganoderenic Acid C, ganoderic Acid C2, ganoderic Acid G, ganoderic Acid B, ganoderenic Acid B, ganoderic Acid A, ganoderic Acid H, ganoderenic Acid D, ganoderic Acid D, ganoderic Acid F, ganoderic Acid DM, ganoderol A, and ergosterol) were selected as the chemical markers. The purpose of this study is to develop an HPLC-DAD fingerprint method for quantification of these active components in GL (spore and fruiting body) and test the feasibility of using the HPLC-DAD fingerprint for quality control or identity determination of GL products.
The results showed that this method could determine the levels of the major components accurately and precisely. Among the 13 components, 11 ganoderma acids were identified to be proper chemical markers for quality control of GL products, while ganoderal A was in a very low amount and ergosterol was not a specific marker in GL. The extracts of fruiting body contained more chemical compounds than those of spore, indicating that these 11 compounds could be a better chemical marker for the fruiting body than the spore. The HPLC chemical fingerprint analysis showed higher variability in the quality of GL harvest in different years, while lesser variation in batches harvested in the same year.
In conclusion, an HPLC assay detecting 11 major active components and a fingerprinting method was successfully established and validated to be feasible for quality control of most commercial GL products.
Background and aims
This large-scale study aimed to test (a) associations of problematic Internet use (PIU) and sleep disturbance with suicidal ideation and suicide attempts among Chinese adolescents and (b) whether sleep disturbance mediates the association between PIU and suicidal behavior.
Methods
Data were drawn from the 2017 National School-based Chinese Adolescents Health Survey. A total of 20,895 students’ questionnaires were qualified for analysis. The Young’s Internet Addiction Test was used to assess PIU, and level of sleep disturbance was measured by the Pittsburgh Sleep Quality Index. Multilevel logistic regression models and path models were utilized in analyses.
Results
Of the total sample, 2,864 (13.7%) reported having suicidal ideation, and 537 (2.6%) reported having suicide attempts. After adjusting for control variables and sleep disturbance, PIU was associated with an increased risk of suicidal ideation (AOR = 1.04, 95% CI = 1.03−1.04) and suicide attempts (AOR = 1.03, 95% CI = 1.02−1.04). Findings of the path models showed that the standardized indirect effects of PIU on suicidal ideation (standardized β estimate = 0.092, 95% CI = 0.082−0.102) and on suicide attempts (standardized β estimate = 0.082, 95% CI = 0.068−0.096) through sleep disturbance were significant. Conversely, sleep disturbance significantly mediated the association of suicidal behavior on PIU.
Discussion and conclusions
There may be a complex transactional association between PIU, sleep disturbance, and suicidal behavior. The estimates of the mediator role of sleep disturbance provide evidence for the current understanding of the mechanism of the association between PIU and suicidal behavior. Possible concomitant treatment services for PIU, sleep disturbance, and suicidal behavior were recommended.
