Molecular evolution of Cide family proteins: Novel domain formation in early vertebrates and the subsequent divergence

<p>Abstract</p> <p>Background</p> <p>Cide family proteins including Cidea, Cideb and Cidec/Fsp27, contain an N-terminal CIDE-N domain that shares sequence similarity to the N-terminal CAD domain (NCD) of DNA fragmentation factors Dffa/Dff45/ICAD and Dffb/Dff40/CAD, and a unique C-terminal CIDE-C domain. We have previously shown that Cide proteins are newly emerged regulators closely associated with the development of metabolic diseases such as obesity, diabetes and liver steatosis. They modulate many metabolic processes such as lipolysis, thermogenesis and TAG storage in brown adipose tissue (BAT) and white adipose tissue (WAT), as well as fatty acid oxidation and lipogenesis in the liver.</p> <p>Results</p> <p>To understand the evolutionary process of Cide proteins and provide insight into the role of Cide proteins as potential metabolic regulators in various species, we searched various databases and performed comparative genomic analysis to study the sequence conservation, genomic structure, and phylogenetic tree of the CIDE-N and CIDE-C domains of Cide proteins. As a result, we identified signature sequences for the N-terminal region of Dffa, Dffb and Cide proteins and CIDE-C domain of Cide proteins, and observed that sequences homologous to CIDE-N domain displays a wide phylogenetic distribution in species ranging from lower organisms such as hydra (<it>Hydra vulgaris</it>) and sea anemone (<it>Nematostella vectensis</it>) to mammals, whereas the CIDE-C domain exists only in vertebrates. Further analysis of their genomic structures showed that although evolution of the ancestral CIDE-N domain had undergone different intron insertions to various positions in the domain among invertebrates, the genomic structure of <it>Cide </it>family in vertebrates is stable with conserved intron phase.</p> <p>Conclusion</p> <p>Based on our analysis, we speculate that in early vertebrates CIDE-N domain was evolved from the duplication of NCD of Dffa. The CIDE-N domain somehow acquired the CIDE-C domain that was formed around the same time, subsequently generating the Cide protein. Subsequent duplication and evolution have led to the formation of different Cide family proteins that play unique roles in the control of metabolic pathways in different tissues.</p

Holistic Strategies Lead to Enhanced Efficiency and Stability of Hybrid Chemical Vapor Deposition Based Perovskite Solar Cells and Modules

Hybrid chemical vapor deposition (HCVD) is a promising method for the up-scalable fabrication of perovskite solar cells/modules (PSCs/PSMs). However, the efficiency of the HCVD-based perovskite solar cells still lags behind the solution-processed PSCs/PSMs. In this work, the oxygen loss of the electron transport layer of SnO2 in the HCVD process and its negative impact on solar cell device performance are revealed. As the counter-measure, potassium sulfamate (H2KNO3S) is introduced as the passivation layer to both mitigate the oxygen loss issue of SnO2 and passivate the uncoordinated Pb2+ in the perovskite film. In parallel, N-methylpyrrolidone (NMP) is used as the solvent to dissolve PbI2 by forming the intermediate phase of PbI2•NMP, which can greatly lower the energy barrier for perovskite nucleation in the HCVD process. The perovskite seed is employed to further modulate the kinetics of perovskite crystal growth and improve the grain size. The resultant solar cells yield a champion power conversion efficiency (PCE) of 21.98% (0.09 cm2) with a stable output performance of 21.15%, and the PCEs of the mini-modules are 16.16% (22.4 cm2, stable output performance of 14.72%) and 12.12% (91.8 cm2). Furthermore, the unencapsulated small area device shows an outstanding operational stability with a T80 lifetime exceeding 4000 h.journal articl

Of Natural Killer cells and Hepatitis C Virus

Natural Killer (NK) cells are important effector cells in Hepatitis C Virus (HCV) infection, a virus that chronically infects around 2.5% of the world population and is a major cause of liver disease and hepatocellular carcinoma. The exact mechanisms, however, through which NK cells are activated in response to HCV remain elusive. Using the well-established HCV replicon cell-culture model we show that after co- culture of HCV replicon-carrying hepatocytes with peripheral blood mononuclear cells (PBMCs), NK cells increase expression of the high-affinity IL-2 receptor chain CD25, proliferate rapidly and produce IFN-gamma. Activation of NK cells was dependent on IL-2, most likely produced by T cells and on cell-cell contact mediated signals from monocytes. Monocytes from replicon-carrying co-cultures showed increased expression of OX40L, a member of the tumor necrosis factor family and concurrently its receptor OX40 was increased on NK cells. Blocking of OX40L in those co-cultures, as well as depletion of CD14+ monocytes abrogated the virus-induced activation and effector functions of NK cells. Together, our data reveals a novel mechanism of monocyte mediated NK cell activation against virus-infected cells involving the OX40/OX40L axis with potential relevance for therapeutic intervention by e.g. agonistic antibodies against OX40, which are already tested in cancer therapy

Constructing Heterostructure through Bidentate Coordination toward Operationally Stable Inverted Perovskite Solar Cells

It has been reported that one of the influencing factors leading to stability issues in iodine-containing perovskite solar cells is the iodine loss from the perovskite layer. Herein, bidentate coordination is used with undercoordinated I− of the perovskite surface to construct the stable perovskite-based heterostructure. This strong halogen bonding effectively inhibits interfacial migration of I− into functional layers such as C60 and Ag. Moreover, passivation of the undercoordinated I− suppresses the release of I2 and further delays the formation of voids at the perovskite surface. The resulting inverted perovskite solar cell exhibits a power conversion efficiency of 22.59% and the unencapsulated device maintains 96.15% of its initial value after continuous operation for 500 h under illumination.journal articl

Graphene‐Like Conjugated Molecule as Hole‐Selective Contact for Operationally Stable Inverted Perovskite Solar Cells and Modules

Further enhancing the operational lifetime of inverted-structure perovskite solar cells (PSCs) is crucial for their commercialization, and the design of hole-selective contacts at the illumination side plays a key role in operational stability. In this work, the self-anchoring benzo[rst]pentaphene (SA-BPP) is developed as a new type of hole-selective contact toward long-term operationally stable inverted PSCs. The SA-BPP molecule with a graphene-like conjugated structure shows a higher photostability and mobility than that of the frequently-used triphenylamine and carbazole-based hole-selective molecules. Besides, the anchoring groups of SA-BPP promote the formation of a large-scale uniform hole contact on ITO substrate and efficiently passivate the perovskite absorbers. Benefiting from these merits, the champion efficiencies of 22.03% for the small-sized cells and 17.08% for 5 × 5 cm2 solar modules on an aperture area of 22.4 cm2 are achieved based on this SA-BPP contact. Also, the SA-BPP-based device exhibits promising operational stability, with an efficiency retention of 87.4% after 2000 h continuous operation at the maximum power point under simulated 1-sun illumination, which indicates an estimated T80 lifetime of 3175 h. This novel design concept of hole-selective contacts provides a promising strategy for further improving the PSC stability.journal articl

Elimination of light-induced degradation at the nickel oxide-perovskite heterojunction by aprotic sulfonium layers towards long-term operationally stable inverted perovskite solar cells

Nickel oxide (NiOx) is a promising hole-selective contact to produce efficient inverted p-i-n structured perovskite solar cells (PSCs) due to its high carrier mobility and high transparency. However, the light-induced degradation of the NiOx–perovskite heterojunction is the main factor limiting its long-term operational lifetime. In this study, we used the time-resolved mass spectrometry technique to clarify the degradation mechanism of the NiOx-formamidinium–methylammonium iodide perovskite (a common composition for high-performance PSCs) heterojunction under operational conditions, and observed that (1) oxidation of iodide and generation of free protons under 1-sun illumination, (2) formation of volatile hydrogen cyanide, methyliodide, and ammonia at elevated temperatures, and (3) a condensation reaction between the organic components under a high vapor pressure. To eliminate these multi-step photochemical reactions, we constructed an aprotic trimethylsulfonium bromide (TMSBr) buffer layer at the NiOx/perovskite interface, which enables excellent photo-thermal stability, a matched lattice parameter with the perovskite crystal, and robust trap-passivation ability. Inverted PSCs stabilized with the TMSBr buffer layer reached the maximum efficiency of 22.1% and retained 82.8% of the initial value after continuous operation for 2000 hours under AM1.5G light illumination, which translates into a T80 lifetime of 2310 hours that is among the highest operational lifetimes for NiOx-based PSCs

Set-membership filtering for generator dynamic state estimation with delayed measurements

In this paper, the set-membership filtering problem is investigated for the dynamic state estimation (DSE) of the synchronous generator with delayed measurements. The process noise and measurement noise are assumed to be unknown, bounded and confined to a specified ellipsoidal set. The measurement delay is modeled by a special matrix composed of a delay-driven variable taking values of 1 or 0. Taking into explicit consideration the estimation uncertainty due to the linearization, the constrained Quasi-Newton method is adopted to minimize the linearization errors. The aim of this paper is to design a set-membership filter capable of confining the state estimate of the system to a certain ellipsoidal region, and the ellipsoidal set including all possible states is obtained by the convex optimization approach. Finally, the proposed algorithm is verified on a single machine infinite bus system to further demonstrate its effectiveness

Mitigating the Trade-Off between Non-Radiative Recombination and Charge Transport to Enable Efficient Ternary Organic Solar Cells

Ternary organic solar cells (OSCs) have attracted intensive studies due to their promising potential for attaining high-performing photovoltaics, whereas there has been an opening challenge in minimizing the open circuit voltage (Voc) loss while retaining the optimal carrier extraction in the multiple mixture absorbers. Here, we systemically investigate a ternary absorber comprised of two acceptors and a donor, in which the resultant Voc and fill factor are varied and determined by the ratios of acceptor components as a result of the unbalance of non-radiative recombination rates and charge transport. The transient absorption spectroscopy and electroluminescence techniques verify two distinguishable charge-transfer (CT) states in the ternary absorber, and the mismatch of non-radiative recombination rates of those two CT states is demonstrated to be associated with the Voc deficit, whilst the high-emissive acceptor molecule delivers inferior electron mobility, resulting in poor charge transport and a subpar fill factor. These findings enable us to optimize the mixture configuration for attaining the maximal-performing devices. Our results not only provide insight into maximizing the photovoltage of organic solar cells but can also motivate researchers to further unravel the photophysical mechanisms underlying the intermolecular electronic states of organic semiconductors

Recent progress of rare earth nanoparticles as magnetic resonance imaging contrast agents

Rare earth ions,owing to their unique 4f electron configurations,exhibit unique optical and magnetic properties.These rare earth nanoparticles are widely used as magnetic resonance imaging contrast agents.This paper reviews the classification,synthesis methods,and applications for magnetic resonance imaging of rare earth nanoparticles and makes some outlook