Testis-specific glyceraldehyde-3-phosphate dehydrogenase: origin and evolution

<p>Abstract</p> <p>Background</p> <p>Glyceraldehyde-3-phosphate dehydrogenase (GAPD) catalyses one of the glycolytic reactions and is also involved in a number of non-glycolytic processes, such as endocytosis, DNA excision repair, and induction of apoptosis. Mammals are known to possess two homologous GAPD isoenzymes: GAPD-1, a well-studied protein found in all somatic cells, and GAPD-2, which is expressed solely in testis. GAPD-2 supplies energy required for the movement of spermatozoa and is tightly bound to the sperm tail cytoskeleton by the additional N-terminal proline-rich domain absent in GAPD-1. In this study we investigate the evolutionary history of GAPD and gain some insights into specialization of GAPD-2 as a testis-specific protein.</p> <p>Results</p> <p>A dataset of GAPD sequences was assembled from public databases and used for phylogeny reconstruction by means of the Bayesian method. Since resolution in some clades of the obtained tree was too low, syntenic analysis was carried out to define the evolutionary history of GAPD more precisely. The performed selection tests showed that selective pressure varies across lineages and isoenzymes, as well as across different regions of the same sequences.</p> <p>Conclusions</p> <p>The obtained results suggest that GAPD-1 and GAPD-2 emerged after duplication during the early evolution of chordates. GAPD-2 was subsequently lost by most lineages except lizards, mammals, as well as cartilaginous and bony fishes. In reptilians and mammals, GAPD-2 specialized to a testis-specific protein and acquired the novel N-terminal proline-rich domain anchoring the protein in the sperm tail cytoskeleton. This domain is likely to have originated by exonization of a microsatellite genomic region. Recognition of the proline-rich domain by cytoskeletal proteins seems to be unspecific. Besides testis, GAPD-2 of lizards was also found in some regenerating tissues, but it lacks the proline-rich domain due to tissue-specific alternative splicing.</p

Exploring effective built environment factors for evaluating pedestrian volume in high-density areas: a new finding for the Central Business District in Melbourne, Australia

Previous studies have mostly examined how sustainable cities try to promote non-motorized travel by creating a walking-friendly environment. Such existing studies provide little data that identifies how the built environment affects pedestrian volume in high-density areas. This paper presents a methodology that combines person correlation analysis, stepwise regression, and principal component analysis for exploring the internal correlation and potential impact of built environment variables. To study this relationship, cross-sectional data in the Melbourne central business district were selected. Pearson&rsquo;s correlation coefficient confirmed that visible green ratio and intersection density were not correlated to pedestrian volume. The results from stepwise regression showed that land-use mix degree, public transit stop density, and employment density could be associated with pedestrian volume. Moreover, two principal components were extracted by factor analysis. The result of the first component yielded an internal correlation where land-use and amenities components were positively associated with the pedestrian volume. Component 2 presents parking facilities density, which negatively relates to the pedestrian volume. Based on the results, existing street problems and policy recommendations were put forward to suggest diversifying community service within walking distance, improving the service level of the public transit system, and restricting on-street parking in Melbourne

Efficient charge separation between UiO-66 and ZnIn2S4 flowerlike 3D microspheres for photoelectronchemical properties

It is still a great challenge to develop efficient semiconductive photocatalysts responding to visible light radiation. We show an efficient ZnIn2S4/UiO-66 hybrid photocatalysts with flowerlike 3D microspheres synthesized via a facile solvothermal method. A 20 wt.% UiO-66 emersion raises the Cr(VI) reduction rate up to 99% and higher after 60 min visible light irradiation. The substantial enhancement of photocatalytic and photoelectronchemical activity of pure ZnIn2S4 by UiO-66 addition is attributed to the ZnIn2S4/UiO-66 interfacial charge transferring and more active sites for pollute adsorption

ZnIn2S4 flowerlike microspheres embedded with carbon quantum dots for efficient photocatalytic reduction of Cr(VI)

Development of efficient heterostructured photocatalysts that respond to visible light remains a considerable challenge. We herein show the synthesis of ZnIn2S4/carbon quantum dot hybrid photocatalysts with flowerlike microspheres via a facile solvothermal method. The ZnIn2S4/carbon quantum dot flowerlike microspheres display enhanced photocatalytic and photoelectrochemical activity compared with that of pure ZnIn2S4. With a content of only 0.5 wt % carbon quantum dots, 93% of Cr(VI) is reduced under visible-light irradiation at 40 min. As a co-catalyst, the carbon quantum dots improve the light absorption and lengthen the lifetime of charge carriers, consequently enhancing the photocatalytic and photoelectrochemical activity

CuS/RGO hybrid photocatalyst for full solar spectrum photoreduction from UV/Vis to near-infrared light

To make full use of the solar energy, it remains a great challenge for semiconductor photocatalysts to harvest the full solar light spectrum from ultraviolet (UV) to visible even the near infrared (NIR) wavelength. Here we show firstly the CuS/RGO (reduced graphene oxide) hybrid photocatalyst synthesized via a microwave assisted method with full solar light (UV-Vis-NIR) active for efficient Cr(VI) reduction. The CuS/RGO displays high absorption and catalytic activity in the UV, visible and even the NIR light regions. As co-catalyst, RGO can separate and inhibit the recombination of charge carriers, consequently improving the catalytic activity. Only 1wt% RGO emersions can reduce 90% of Cr(VI) under the radiation of light over the full spectrum. Findings may provide a new strategy and substance to expand the utilization range of solar light from UV to visible even the NIR energy

Cu2In2ZnS5/Gd2O2S:Tb for full solar spectrum photoreduction of Cr(VI) and CO2 from UV/vis to near-infrared light

Full solar spectrum active heterogenous photocatalysis for environmental applications remains highly challenging. Here we report the novel Cu2In2ZnS5/Gd2O2S:Tb (CG) hybrid photocatalysts via a facile solvothermal method for efficient Cr(VI) and CO2 reduction. The narrow band gap energies of the CG hybrid photocatalysts synthesized via a facile solvothermal method show excellent absorption and catalytic activity in the full solar spectrum. High Cr(VI) reduction rate of 90% and CH4 production rate of 57.73 μmol h−1 g−1 are achieved for CG hybrid photocatalyst with 1 wt.% Gd2O2S:Tb. The excellent performance is due to the fact that in the hybrid, Gd2O2S:Tb as cocatalyst, provides more active sites and inhibits the recombination of charge carriers due to the synergetic effect between Cu2In2ZnS5 and Gd2O2S:Tb, consequently improving the photocatalytic reduction activity.Financial support from the Province Natural Science Foundation of Zhejiang (No. LY18E060005, LY18E020007 and LQ18E030005), National Natural Science Foundation of China (No. 21401180) are gratefully acknowledged

CaIn2S4 decorated WS2 hybrid for efficient Cr(VI) reduction

Exploiting efficient visible light active photocatalyst is a great challenge with potential applications such as environmental pollution and solar energy conversion. Herein, a series of CaIn 2 S 4 /WS 2 hybrids was fabricated via a simple hydrothermal method. WS 2 as cocatalyst increases the visible light absorption and separation efficient of charge carrier at the interface, leading to the enhanced photocatalytic activity of CaIn 2 S 4 /WS 2 . CaIn 2 S 4 /20 wt% WS 2 hybrid shows the highest Cr(VI) reduction rate of 98% and methyl orange degradation rate of 96%. This work could offer some thought for designing and fabricating hybrid photocatalyst with high efficient and stable activity.Financial support from the province Natural Science Foundation of Zhejiang Province (No. LY18E060005, LY18E020007, LY19E020006 and LQ18E030005) is gratefully acknowledged

Interfacial gradient energy band alignment modulation via ion exchange reaction toward efficient and stable methylammonium-free Dion-Jacobson quasi-2D perovskite solar cells

Dion-Jacobson (DJ) quasi-2D perovskite solar cells (PSCs) have attracted significant attention owing to its greater potentials in realizing efficient and stable quasi 2D PSCs as compared to Ruddlesden-Popper counterpart. To further enhance power conversion efficiency (PCE) and stability, the fabrication of methylammonium-free formamidinium (FA)-based DJ quasi-2D PSCs is highly desirable. Herein, we report a strategy for constructing gradient energy band alignment by achieving gradient Br doping (GBD) via in situ ion exchange reaction between I and Br in FA-based DJ quasi-2D PSCs. First, the gradient energy band alignment can facilitate carrier transport, extraction and transfer. Second, the improved crystallinity and reduced defect density due to recrystallization process are realized after FABr treatment. Finally, the incorporation of Br also contributes to increased device stability. The device with GBD achieves a much higher PCE of 16.75% than control device (13.78%), which is mainly as a consequence of a significantly boosted V-OC from 0.970 V to 1.107 V due to suppressed bulk and interfacial nonradiative recombination. The unencapsulated device with GBD maintains 93% of its initial PCE after aging under the relative humidity range of 15-20% for 1600 h, and 91% after aging at 60 degrees C for 400 h.11Nsciescopu

Crystal Orientation Modulation and Defect Passivation for Efficient and Stable Methylammonium-Free Dion-Jacobson Quasi-2D Perovskite Solar Cells

Dion-Jacobson (DJ) quasi-2D perovskite solar cells (PSCs) have received increasing attention due to their greater potentials in realizing efficient and stable quasi-2D PSCs relative to their Ruddlesden-Popper counterpart. The substitution of methylammonium (MA(+)) with formamidinium is expected to be able to further increase the stability and power conversion efficiency (PCE) of DJ quasi-2D PSCs. Herein, we report a multifunctional additive strategy for preparing high-quality MA-free DJ quasi-2D perovskite films, where 1,1&apos;-carbonyldi(1,2,4-triazole) (CDTA) molecules are incorporated into the perovskite precursor solution. CDTA modification can control phase distribution, enlarge grain size, modulate crystallinity and crystal orientation, and passivate defects. After CDTA modification, more favorable gradient phase distribution and accordingly gradient band alignment are formed, which is conducive to carrier transport and extraction. The improved crystal orientation can facilitate carrier transport and collection. The enlarged grain size and effective defect passivation contribute to reduced defect density. As a result, the CDTA-modified device delivers a PCE of 16.07%, which is one of the highest PCEs ever reported for MA-free DJ quasi-2D PSCs. The unencapsulated device with CDTA maintains 92% of its initial PCE after aging under one sun illumination for 360 h and 86% after aging at 60 degrees C for 360 h.11Nsciescopu

Interfacial defect passivation by novel phosphonium salts yields 22% efficiency perovskite solar cells: Experimental and theoretical evidence

We modified perovskite/Spiro-OMeTAD interface by using two novel phosphonium salts containing PF6− counter anion (i.e., ClTPPPF6 and BrTPPPF6). The cation and anion in phosphonium salts possess not only ionic bonds but also coordination bonds with perovskites. The anion and cation vacancies at the surface and GBs of perovskite films can be filled by phosphonium cations and PF6− anions, respectively, resulting in reduced defect density and prolonged carrier lifetimes. The stronger chemical interaction and accordingly better defect passivation were certified for BrTPPPF6 than ClTPPPF6. As a result, the devices modified by ClTPPPF6 and BrTPPPF6 deliver a PCE of 21.73% and 22.15%, respectively, which far exceed 20.6% of the control device. The unsealed BrTPPPF6 modified device maintains 98.2% of its initial efficiency value after thermal aging of 1320 h whereas merely 84.7% for the control device. 96.4% of its original efficiency was retained for BrTPPPF6-modified device after ambient exposure of 2016 h.11Ysci