Comprehensive Bibliometric Analysis of the Kynurenine Pathway in Mood Disorders: Focus on Gut Microbiota Research

Background: Emerging evidence implicates the dysregulated kynurenine pathway (KP), an immune-inflammatory pathway, in the pathophysiology of mood disorders (MD), including depression and bipolar disorder characterized by a low-grade chronic pro-inflammatory state. The metabolites of the KP, an important part of the microbiota-gut-brain axis, serve as immune system modulators linking the gut microbiota (GM) with the host central nervous system.Aim: This bibliometric analysis aimed to provide a first glimpse into the KP in MD, with a focus on GM research in this field, to guide future research and promote the development of this field.Methods: Publications relating to the KP in MD between the years 2000 and 2020 were retrieved from the Scopus and Web of Science Core Collection (WoSCC), and analyzed in CiteSpace (5.7 R5W), biblioshiny (using R-Studio), and VOSviewer (1.6.16).Results: In total, 1,064 and 948 documents were extracted from the Scopus and WoSCC databases, respectively. The publications have shown rapid growth since 2006, partly owing to the largest research hotspot appearing since then, “quinolinic acid.” All the top five most relevant journals were in the neuropsychiatry field, such as Brain Behavior and Immunity. The United States and Innsbruck Medical University were the most influential country and institute, respectively. Journal co-citation analysis showed a strong tendency toward co-citation of research in the psychiatry field. Reference co-citation analysis revealed that the top four most important research focuses were “kynurenine pathway,” “psychoneuroimmunology,” “indoleamine 2,3-dioxygenase,” and “proinflammatory cytokines,” and the most recent focus was “gut-brain axis,” thus indicating the role of the KP in bridging the GM and the host immune system, and together reflecting the field’s research foundations. Overlap analysis between the thematic map of keywords and the keyword burst analysis revealed that the topics “Alzheimer’s disease,” “prefrontal cortex,” and “acid,” were research frontiers.Conclusion: This comprehensive bibliometric study provides an updated perspective on research associated with the KP in MD, with a focus on the current status of GM research in this field. This perspective may benefit researchers in choosing suitable journals and collaborators, and aid in the further understanding of the field’s hotspots and frontiers, thus facilitating future research

Hsa-miR-196a2 Rs11614913 Polymorphism Contributes to Cancer Susceptibility: Evidence from 15 Case-Control Studies

BACKGROUND: MicroRNAs (miRNAs) are a family of endogenous, small and noncoding RNAs that negatively regulate gene expression by suppressing translation or degrading mRNAs. Recently, many studies investigated the association between hsa-miR-196a2 rs11614913 polymorphism and cancer risk, which showed inconclusive results. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a meta-analysis of 15 studies that included 9,341 cancer cases and 10,569 case-free controls. We assessed the strength of the association, using odds ratios (ORs) with 95% confidence intervals (CIs). Overall, individuals with the TC/CC genotypes were associated with higher cancer risk than those with the TT genotype (OR=1.18, 95% CI=1.03-1.34, P<0.001 for heterogeneity test). In the stratified analyses, we observed that the CC genotype might modulate breast cancer risk (OR=1.11, 95%CI=1.01-1.23, Pheterogeneity=0.210) and lung cancer risk (OR=1.25, 95%CI=1.06-1.46, Pheterogeneity=0.958), comparing with the TC/TT genotype. Moreover, a significantly increased risk was found among Asian populations in a dominant model (TC/CC versus TT, OR=1.24, 95% CI=1.07-1.43, Pheterogeneity=0.006). CONCLUSIONS: These findings supported that hsa-miR-196a2 rs11614913 polymorphism may contribute to the susceptibility of cancers

Experimental study on a diode-pumped Nd : CTGG solid-state laser

This report documents the study and construction of a Diode-Pumped Solid State Laser (DPSSL), using Neodymium (Nd3+) doped calcium tantalum gallium garnet (Nd:CTGG) crystal as the active gain medium. A fiber coupled laser diode operating at a wavelength of 808nm is used as the pump source. A simple two-mirror laser system is constructed and continuous-wave (CW) output operation at a central wavelength around 1064nm is achieved. The report gives a detailed description of the laser construction and alignment process. Various sets of mirrors with different parameters have been used to form the laser cavity. Laser output power is measured using a photo detector. The Output power verses input power curve is plotted and the laser slope efficiency is calculated. And laser output spectrum is measured by an optical spectra meter. Different sets of the results of the laser performance is compared and analyzed.Bachelor of Engineerin

Fabrication and characterization of ytterbium doped transparent laser ceramics

Transparent laser ceramics have shown great application potentials as the host materials of solid state lasers, because of their excellent physical and stable chemical properties. Solid state lasers have wide applications in the fields of industry, communication, medical and military, such as laser drilling and welding, laser surgery and even laser weapons. Compared with their single crystal counterparts, polycrystalline ceramics possess various advantages, such as shorter fabrication period, higher yield for mass production, higher ion doping concentration, feasibility to be large sizes with complex shapes and structures, and overall lower fabrication cost. Among various laser ceramics, ytterbium (Yb 3+ ) ion doped ones have been considered to be very attractive solid state laser materials. Yb 3+ ion has unique properties, including high quantum efficiency, long fluorescence lifetime and broad emission spectrum. Its broad absorption band is especially useful for direct laser diode pumping. Yttrium aluminum garnet (YAG)is a very popular laser host materials, because of its high hardness, high thermal conductivity and stable chemical property. Its cubic crystal structure is also important to achieve high optical transparency. However, processing and fabrication of transparent ceramics with high optical transparency is still a challenge. The work in this thesis is focused on the development of ytterbium doped transparent laser ceramics, mainly based on YAG garnet. By using high purity Yb2O3, Al2O3 and Y2O3 powders as starting materials, ytterbium doped YAG (Yb:YAG) ceramics with different concentrations of Yb were fabricated by using the conventional solid-state reaction process, combined with vacuum sintering technique. XRD results showed that all samples obtained were of pure garnet phase. SEM characterization results revealed that all samples had very dense and pore-free microstructure, with the average grain size of about 10 µm. According to spectroscopic studies, the Yb:YAG laser ceramics exhibited the in-line transmittance of 83% at room temperature, which was very close to their theoretical transparency. The high optical quality assured that the samples can be used for practical laser applications. As a result, the Yb:YAG ceramics demonstrated absorption and emission cross-section of 0.72×10^(-20) cm^2 and 2.01×^(-20) cm^2, respectively. A diode pumped solid state laser system has been set up by using the Yb:YAG ceramics as the laser medium. Continuous wave (CW) laser operation was successfully achieved. The 5.0 at.% doped Yb:YAG sample had a maximum output power of 6.2 W, corresponding to a laser efficiency of 62%. Broader gain spectra have been achieved by adjusting the composition of the garnet host materials. In this respect, transparent ytterbium doped gadolinium yttrium aluminum garnets (Yb:GdYAG), i.e., mixed garnet ceramics, have been developed. This new type of mixed garnet ceramics could be used for laser applications with promising performances. Correspondingly, CW and passive mode-locking laser operations have been experimentally investigated. The technique developed for Yb:YAG was further extended to lutetium aluminum garnet (LuAG). This is because LuAG higher thermal conductivity and thus has high potential as the host laser ceramics for high power laser applications, due to the better thermal management. Experimentally, the Yb:LuAG ceramics exhibited an emission cross-section of 2.7×10^(-20) cm^2, which was higher than that of Yb:YAG by about 35%. CW laser performance of the sample was characterized, with an output power of 7.2 W and slope efficiency of 65%. Femtosecond mode-locked laser operation was also realized with 650 fs pulse duration by using the Yb:LuAG ceramics. Based on the achievements, it is expected that Yb doped sesquioxide ceramics with even higher thermal properties could be considered to be new laser materials as the future works, which have been supported by preliminary results.Doctor of Philosophy (MSE

Combining aesthetic with ecological values for landscape sustainability.

Humans receive multiple benefits from various landscapes that foster ecological services and aesthetic attractiveness. In this study, a hybrid framework was proposed to evaluate ecological and aesthetic values of five landscape types in Houguanhu Region of central China. Data from the public aesthetic survey and professional ecological assessment were converted into a two-dimensional coordinate system and distribution maps of landscape values. Results showed that natural landscapes (i.e. water body and forest) contributed positively more to both aesthetic and ecological values than semi-natural and human-dominated landscapes (i.e. farmland and non-ecological land). The distribution maps of landscape values indicated that the aesthetic, ecological and integrated landscape values were significantly associated with landscape attributes and human activity intensity. To combine aesthetic preferences with ecological services, the methods (i.e. field survey, landscape value coefficients, normalized method, a two-dimensional coordinate system, and landscape value distribution maps) were employed in landscape assessment. Our results could facilitate to identify the underlying structure-function-value chain, and also improve the understanding of multiple functions in landscape planning. The situation context could also be emphasized to bring ecological and aesthetic goals into better alignment

Microwave photon detection scheme based on hybrid cavity system

We present a microwave photon detection scheme based on wavelength conversion in hybrid cavity system (electro-opto-mechanical converter). By converting microwave pulse into optical pulse efficiently, tough microwave photon detection can be switched to convenient optical photon detection. We demonstrate that a theoretical detection efficiency analogous to optical detection efficiency can be reached by selecting proper parameters. Pulse shapes of both wavelengths match well. Furthermore, we enhance the scheme by applying the Josephson parametric amplifier (JPA) and optical parametric amplifier (OPA) in the respective cavity, and we obtain a maximum detection efficiency enhancement of near 41% compared to the non-amplification case

How the Sodium Cations in Anode Affect the Performance of a Lithium-ion Battery

Large cations such as potassium ion (K+) and sodium ion (Na+) could be introduced into the lithium-ion (Li-ion) battery system during material synthesis or battery assembly. However, the effect of these cations on charge storage or electrochemical performance has not been fully understood. In this study, sodium ion was taken as an example and introduced into the lithium titanium oxide (LTO) anode through the carboxymethyl cellulose (CMC) binder. After the charge/discharge cycles, these ions doped into the LTO lattice and improved both the lithium-ion diffusivity and the electronic conductivity of the anode. The sodium ion&rsquo;s high concentration (&gt;12.9%), however, resulted in internal doping of Na+ into the LTO lattice, which retarded the transfer of lithium ions due to repulsion and physical blocking. The systematic study presented here shows that large cations with an appropriate concentration in the electrode would be beneficial to the electrochemical performance of the Li-ion battery