mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
Impact of oceans on climate change in drylands

Drylands account for approximately 41% of the global total land area. Significant warming and rare precipitation in drylands result in a fragile ecology and deterioration of the living environment, making it more sensitive to global climate change. As an important regulator of the Earth's climate system, the oceans play a vital role in the process of climate change in drylands. In modern climate change in particular, the impact of marine activities on climate change in drylands cannot be neglected. This paper reviews the characteristics of climate change in drylands over the past 100 years, and summarizes the researches conducted on the impact of marine activities on these changes. The review focuses on the impact of the Pacific Decadal Oscillation (PDO), Atlantic Multidecadal Oscillation (AMO), El Nino and La Nina on climate change in drylands, and introduces the mechanisms by which different oceanic oscillation factors synergistically affect climate change in drylands. Studies have shown that global drylands have experienced a significant intensification in warming in the past 100 years, which shows obvious characteristics of interdecadal dry/wet variations. The characteristics of these changes are closely related to the oscillatory factors of the oceanic interdecadal scale. Different phase combinations of oceanic oscillation factors significantly change the land-sea thermal contrast, which in turn affects the westerly jet, planetary wave and blocking frequency, resulting in changes in the temperature and dry/wet characteristics of drylands. With the intensification of climate change in drylands, the impact of marine activities on these regions will reveal new characteristics in the future, which will increase the uncertainty of future climate change in drylands and intensify the impact of these drylands on global climate.
Seasonal and reproductive variation in chemical constituents of scent signals in wild giant pandas

Seasonally reproducing animals show many behavioral and physiological changes during the mating period, including increased signaling for intrasexual competition and mate attraction. We collected 102 anogenital gland secretions (AGS) from marking trees in Foping Nature Reserve, and used gas chromatography mass spectrometry to analyze these chemical composition. Of these marks, all but one were from males, confirmed with DNA analysis. We found that several chemical constituents, especially volatile compounds, were present only during the mating season and that the relative abundance of many compounds changed as a function of breeding season, whereas nonvolatile compounds were lower in the mating season. This seasonal variation in chemical composition of AGS most likely plays an important role in governing giant panda reproduction, including mate location, attraction, and male-male competition. The chemical properties of many of these putative chemosignals—such as volatility and longevity—are suggestive of these roles, and undoubtedly contribute to successful reproduction for this species with a characteristically sophisticated chemical communication system. We also found a number of important differences between the chemical constituents of AGS from wild pandas and those found in previous studies with captive pandas, suggesting that inappropriate chemosignal composition may contribute to poor reproductive success in captive breeding programs.
Synthetic chromosome evolves the yeast genome

Genomic structural variations play a critical role in biological function and phenotypic diversity. Although smallscale variations, such as insertion, deletion, and point mutations, have been extensively investigated, studies on largescale structural variations such as segmental duplication, inversion, and chromosome-scale variations remain limited. In the recent decade, with the development of synthetic biology, particularly the ability to synthesize whole chromosomes in yeast, scientists have been able to interpret the diverse phenotypic mechanisms underlying the complex genome architecture and function.
Phylogenetic relationships of Cypriniformes and plasticity of pharyngeal teeth in the adaptive radiation of cyprinids

The Cypriniformes comprise approximately 4,200 species accounting for 25 %of the diversity of all freshwater fish, which is widely distributed across the world's continents except Antarctica, South America, and Australia. The highest species diversity is found in Southeastern Asia. Despite its remarkable species diversity and broad-scale geographic patterns of distribution, the evolutionary history of this major freshwater fish group remains largely unresolved. To gain insight of the evolutionary history of Cypriniformes, we present a phylogeny of this group using 1 mitochondrial gene and 15 nuclear genes comprising a total of 14,061 bp. Bayesian inference using all gene fragments yielded a well resolved phylogeny, which is mostly consistent with topologies obtained from Maximum Likelihood analyses. Our results further confirmed the monophyly of Cypriniformes and seven constituent subclades including Cyprinidae, Catostomidae, Gyrinocheilidae, Balitoridae, Cobitidae, Nemacheilidae, and Botiidae. Bayesian divergence time analysis indicated that the origin of the Cypriniformes was about 193 Mya during the early Jurassic, coinciding with the onset of the Pangaea breakup. The basal divergence of Cypriniformes is 154 Mya during the late Jurassic. Our findings from molecular divergence and biogeographical analysis indicate the most likely initial geographical range of the ancient Cypriniformes was both East and South Asia (Southeastern area of Mesozoic Laurasia). Moreover, the burst in species diversity in Cyprinidae afforded by the nearly worldwide colonization is possibly in response to the plasticity of pharyngeal dentition. The present study demonstrates that the Cypriniformes was about 193 Mya during the early Jurassic, coinciding with the onset of the Pangaea breakup. The plasticity of pharyngeal dentition of cyprinids might contribute to the burst and radiation of this lineage. The phylogenetic and biogeographic analyses in this study help to improve our understanding of the evolutionary history of this diverse and important freshwater fish group.
Special topic on organic and perovskite photovoltaics

Photovoltaics, as a green technology for converting solar energy into electricity, have shown great promise to address the energy and environmental challenges for the sustainability of human society. In recent years, two types of photovoltaics, consisting of organic semiconductors or perovskites as light absorbers, have experienced a rapid development. The development of organic solar cells(OSC) can be dated back to 1986, since the discovery of a bilayer OSC by Dr. C. W. Tang. Nowadays, OSCs made with polymer donors and small molecule acceptors have surpassed power conversion efficiencies(PCEs) of 16% for single-junction and 17% for tandem devices, through integrated innovative efforts on materials, interfaces, and device architectures. In addition, OSCs exhibit attractive virtues, such as color-tuning, semitransparency, flexibility and light-weight, which in part stems from the versatile chemical properties of organic semiconductors. Perovskite solar cells(PVSCs), consisting of lead halides ABX3 perovskites, have experienced a miraculous development since the first report of CH3NH_3PbI3 PVSCs with an efficiency of 3.8% by Miyasaka in 2009. Within only 10 years of development, the certified efficiency of PVSCs has increased drastically to exceeding 24% nowadays, which is on a par with the best efficiencies achieved for Si based solar cells. As a result, both OSCs and PVSCs receive extensive attention from researchers all over the world. Researchers in China have made great contributions in advancing these two types of solar cells. Due to the exciting breakthroughs achieved in OSCs and PVSCs, we edited this special topic on organic and perovskite photovoltaics for Science China Chemistry. We hope that the papers collected under this special topic will motivate researchers from academia and industry to continue the exciting advances in the field.
Comparative study on pattern recognition receptors in non-teleost ray-finned fishes and their evolutionary significance in primitive vertebrates

Pattern recognition receptors (PRRs) play important roles in innate immunity system and trigger the specific pathogen recognition by detecting the pathogen-associated molecular patterns. The main four PRRs components including Toll-like receptors (TLRs), RIG-I-like receptors (RLRs), NOD-like receptors (NLRs) and C-type lectin receptors (CLRs) were surveyed in the five genomes of non-teleost ray-finned fishes (NTR) including bichir (Polypterus senegalus), American paddlefish (Polyodon spathula), alligator gar (Atractosteus spatula), spotted gar (Lepisosteus oculatus) and bowfin (Amia calva), representing all the four major basal groups of ray-finned fishes. The result indicates that all the four PRRs components have been well established in these NTR fishes. In the RLR-MAVS signal pathway, which detects intracellular RNA ligands to induce production of type I interferons (IFNs), the MAVS was lost in bichir particularly. Also, the essential genes of recognition of Lipopolysaccharide (LPS) commonly in mammals like MD2, LY96 and LBP could not be identified in NTR fishes. It is speculated that TLR4 in NTR fishes may act as a cooperator with other PRRs and has a different pathway of recognizing LPS compared with that in mammals. In addition, we provide a survey of NLR and CLR in NTR fishes. The CLRs results suggest that Group V receptors are absent in fishes and Group II and VI receptors are well established in the early vertebrate evolution. Our comprehensive research of PRRs involving NTR fishes provides a new insight into PRR evolution in primitive vertebrate.
Materials and structures for the electron transport layer of efficient and stable perovskite solar cells

The electron transport layer plays a vital function in extracting and transporting photogenerated electrons, modifying the interface, aligning the interfacial energy level and minimizing the charge recombination in perovskite solar cells. This review summarizes the recent research progress on electron transport materials of metal oxides, organic molecules and multilayers. The doped metal oxides as electron transport materials in regular perovskite solar cells show improved device performance relative to their non-doped counterpart due to enhanced electron mobility and energy level alignment. The non-fullerene organic electron transport materials with better electron mobility and tunable energy level alignment need to be further designed and developed despite their advantages of mechanical flexibility and wide range tunability. The multilayer electron transport materials are suggested to be an important direction of research for efficient and stable perovskite solar cells because of their favorable synergistic interaction.
Modulating morphology via side-chain engineering of fused ring electron acceptors for high performance organic solar cells

In this work, four fused ring electron acceptors (FREAs), 2F-C5, 2F-C6, 2F-C8 and 2F-C10, are developed to investigate the effect of side-chain size on the molecular properties and photovoltaic performance of FREA systematically. The elongation of side-chains in the FREAs not only improves their solubility in the processing solvent, but also enhances their miscibility with the donor PBDB-T. It helps the FREA diffuse into the donor PBDB-T during film-formation, thus leading to the decrease in domain size and domain purity from PBDB-T:2F-C5 to PBDB-T:2F-C10 blend films in sequence. The smaller domain size affords more D/A interfaces to benefit exciton dissociation and inhibit monomolecular recombination. However, severe bimolecular recombination occurs when the domain purity decreases to a critical point. Due to the dual function of the increment of side-chain length, both short-circuit current density (JSC) and fill factor (FF) of devices exhibit an evolution of first increasing then decreasing from 2F-C5, 2F-C6, 2F-C8 to 2F-C10 based OSCs. The PBDB-T:2F-C8 based OSCs get a fine balance in morphology with moderate domain size as well as high domain purity simultaneously for the least charge carrier recombination, thus achieving the highest power conversion efficiency of 12.28% with the best J_(SC) (21.27 mA cm~(–2)) and FF (71.96%).
Origin of enhanced stability in thiocyanate substituted α-FAPbI_3 analogues

In the past few years, hybrid perovskites have emerged as the most promising photovoltaic materials due to their excellent optoelectronic properties, and easy fabrication methods. However, the long-term stability is still the main obstacle for their commercial applications. Recently, thiocyanate-doped hybrid perovskites have shown enhanced stability and impressive efficiency, but the reason is still unknown. Herein, we discussed the enhanced stability of SCN-substituted pseudocubic FABX3(B=Pb~(2+), Sn~(2+); X=I~–, Br~–, and Cl~–) based on the density functional theory. Through a series of calculations of Bader charge transfer, vacancy formation energies of different kinds of vacancies, decomposition enthalpy, phonon density of states, and ab initio molecular dynamics simulation, we conclude that the incorporation of SCN~– can stabilize pseudocubic FABX_3, and attribute the enhanced stability mainly to two factors:(1) the strong interaction between Pb~(2+)/Sn~(2+) and SCN~–, as well as the strong hydrogen bonding between FA~+ and X~–/SCN~–, and(2) the structural tilting induced by the incorporation of SCN~–. These findings provide alternative method for tuning the poor stability of pseudocubic FABX_3, as well as for obtaining high-performance solar cells.
Efficient p-i-n structured perovskite solar cells employing low-cost and highly reproducible oligomers as hole transporting materials

The development of p-i-n structured perovskite solar cells (PSCs) requires more extensive explorations on seeking efficient, low cost and stable hole transporting materials (HTMs). Small molecular HTMs are superior to polymeric ones in terms of synthetic reproducibility as well as purity. However, thin films composed of small molecules are usually labile during the solution-based perovskite deposition. Herein, we propose a molecular engineering strategy of incorporating oligothiophene as conjugation bridge to develop robust oligomer HTMs for p-i-n type PSCs. Upon increasing the oligothiophene chain length from α- bithiophene to α-quaterthiophene and α-hexathiophene, their HOMO energy levels remain unchanged, but their solubility in common organic solvents decreased remarkably, thus greatly enhancing their tolerance to the perovskite deposition. The rational design of oligothiophene chain length can effectively tune their optoelectronic properties as well as thin film stability under polar solvent soaking. The best performance is achieved by an α-quaterthiophene based HTM (QT), showing a high efficiency of 17.69% with fill factor of 0.81, which are comparable to those of a commercially available benchmark polymer HTM (poly[bis (4-phenyl)(2,4-dimethylphenyl) amine], PTAA) based devices fabricated under the same conditions. Our developed oligomer system not only provides the definite molecular structures like small molecule-type HTMs, but also exhibits the excellent filmforming like polymer-type HTMs, thus achieving the well-balanced parameters among solvent tolerance, thin film conductivity, and interfacial charge transfer efficiency, especially building up a platform to develop low cost and reproducible efficient HTMs in p-i-n structured perovskite solar cells.
Fluorination-substitution effect on all-small-molecule organic solar cells

Due to the strong crystallinity and anisotropy of small molecules, matched molecular photoelectric properties and morphologies between small molecules and non-fullerene acceptors are especially important in all-small-molecule organic solar cells(OSCs). Introducing fluorine atoms has been proved as an effective strategy to achieve a high device performance through tuning molecular energy levels, absorption and assembly properties. Herein, we designed a novel benzodithiophene-based small molecule donor BDTF-CA with deep highest occupied molecular orbital(HOMO) energy level. All-small-molecule OSCs were fabricated by combing non-fullerene acceptor IDIC with different fluorine-atom numbers. Two or four fluorine atoms were introduced to the end-capped acceptor of IDIC, which are named as IDIC-2F and IDIC-4F, respectively. With the increase of fluorination from IDIC to IDIC-4F, the open circuit voltage(V_(oc)) of the devices decreased, while hole and electron mobilities of the active layers increased by one order of magnitude. Contributed to the most balanced V_(oc), short-circuit current(J_(sc)) and fill factor(FF), the device based on BDTF-CA/IDIC-2F achieved the highest power conversion efficiency of 9.11%.
Breaking 12% efficiency in flexible organic solar cells by using a composite electrode

The performance of flexible organic solar cells(OSCs) significantly relies on the quality of transparent flexible electrode. Here, we used silver nanowires(AgNWs) with various weight ratios to dope high-conductive poly(3,4-ethylenedioxythiophene): polystyrene sulfonate(PH1000) to optimize the optical and electronic properties of PH1000 film. A high-quality flexible composite electrode PET/Ag-mesh/PH1000:AgNWs-20 with smooth surface, a low sheet resistance of 6 Ω/sq and a high transmittance of 86% at 550-nm wavelength was obtained by doping 20 wt% AgNWs to PH1000(PH1000:AgNWs-20). The flexible OSCs based on the PET/Ag-mesh/PH1000:AgNWs-20 electrode delivered a power conversion efficiency(PCE) of 12.07% with an open circuit voltage(V_(oc)) of 0.826 V, a short-circuit current density(J_(sc)) of 20.90 mA/cm~2 and a fill factor(FF) of 69.87%, which is the highest reported PCE for the flexible indium-tin oxide(ITO)-free OSCs. This work demonstrated that the flexible composite electrodes of PET/Ag-mesh/PH1000:AgNWs are promising alternatives for the conventional PET/ITO electrode, and open a new avenue for developing high-performance flexible transparent electrode for optoelectronic devices.
Isolation and identification of phosphorylated lysine peptides by retention time difference combining dimethyl labeling strategy

Protein phosphorylation plays essential roles in various biological procedures. Despite the well-established enrichment strategies for O-phosphoproteomics, the intrinsic acid lability of N–P phosphoramidate bond (phosphorylation of histidine, arginine and lysine) has impaired the progress of N-phosphoproteomics. Herein, we reported a retention time difference combining dimethyl labeling (ReDD) strategy for the isolation and identification of phosphorylated lysine (pLys) peptides. By such a method, pLys peptide could be isolated under 100000-fold interference of non-phosphorylated peptides. Furthermore, ReDD strategy was applied to map pLys sites from E. coli samples, leading to the identification of 11 pLys sites, among which K26p that originating from autonomous glycyl radical cofactor was validated both in mass spectrometry and HPLC co-elution experiments. Furthermore, 112 pLys sites from 100 proteins were identified in HeLa cells. All these results demonstrate that ReDD could provide a first glimpse into Lys phosphorylation, and could be an important step toward the global perspective on protein phosphorylation.
Similar or different: the same Spiro-core but different alkyl chains with apparently improved device performance of perovskite solar cells

By intelligently utilizing the odd-even effect existing in the melting points of alkanes as presented in the basic textbook of Organic Chemistry, different alkoxy groups were introduced to modify the structure of commercial Spiro-OMeTAD to give new Spiro derivatives of Spiro-OEtTAD, Spiro-OPrTAD, Spiro-OiPrTAD and Spiro-OBuTAD, with the aim to adjust the molecular packing status in perovskite solar cells as hole transporting compounds. Excitedly, with the introduction of ethoxy groups instead of the methoxy ones in Spiro-OMeTAD, Spiro-OEtTAD-based perovskite solar cells demonstrated the highest device performance of 20.16%, higher than that of Spiro-OMeTAD (18.64%).
Optimal bulk-heterojunction morphology enabled by fibril network strategy for high-performance organic solar cells

A bicontinuous network formed spontaneously upon film preparation is highly desirable for bulk-heterojunction (BHJ) organic solar cells (OSCs). Many donor-acceptor (D-A) type conjugated polymers can self-assemble into polymer fibrils in the solid state and such fibril-assembly can construct the morphological framework by forming a network structure, inducing the formation of ideal BHJ morphology. Our recent works have revealed that the fibril network strategy (FNS) can control the blend morphology in fullerene, non-fullerene and ternary OSCs. It has been shown that the formation of fibril network can optimize phase separation scale and ensure efficient exciton dissociation and charge carriers transport, thus leading to impressive power conversion efficiencies (PCEs) and high fill factor (FF) values. We believe that FNS will provide a promising approach for the optimization of active layer morphology and the improvement of photovoltaic performance, and further promote the commercialization of OSCs.
Two-dimensional perovskite capping layer for stable and efficient tin-lead perovskite solar cells

Mixed tin-lead iodide perovskites exhibit the characteristics of low toxicity and improved light harvesting ability up to nearinfrared (NIR) spectral region, making them as an attractive alternative for traditional lead based perovskites. However, the performance of lead-based perovskites solar cells is still far inferior to their lead analogues owing to the unavoidable oxidation of Sn~(2+) to Sn~(4+). Here we introduced two-dimensional (2D) perovskite on the top of three dimensional (3D) perovskite film as a capping layer to reduce the self-oxidation, and thus improved the device stability. 2D capping layer was then confirmed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analysis. The existence of the 2D protecting thin layer significantly reduce the spontaneous Sn~(2+) oxidation, thus improve the device performance and reduce the hysteresis. The phenomena could be ascribed to the improved charge extraction efficiency causing by prohibited nonradiative recombination. On top of this, the photovoltaic devices based on conventional-structure configuration were fabricated. Taking advantage of the 2D capping layer, 2D/3D hybrid perovskite photovoltaic devices achieve a open-circuit voltage (V_(oc)) of 0.77 V with short circuit current density (J_(sc)) of 26.60 mA cm~(–2), delivering the best-performing power conversion efficiency of 15.5%. Moreover, the 2D/3D perovskite devices maintained 60 %its initial efficiency after 40 h exposed in air (humidity around 30%, temperature 22 °C), while 3D perovskite-based devices completely failed.
Relative Gromov-Witten invariants of projective completions of vector bundles

It was proved by Fan and Lee (2016) and Fan (2017) that the absolute Gromov-Witten invariants of two projective bundles P (V_i) → X are identified canonically when the total Chern classes c(V_1) and c(V_2) satisfy c(V_1) = c(V_2) for two bundles V_1 and V_2 over a smooth projective variety X. In this paper, we show that the relative Gromov-Witten invariants of ( P (V_i ⊕ O ), P (V_i)), i = 1, 2 are identified canonically when c(V_1) = c(V_2), where P (V_i ⊕ O ) are the projective completions of the bundles V_i → X, and the projective bundles P (V_i) are the exceptional divisors in P (V_i ⊕ O ).