Search

A porous structure with gradient pores similar to those found in trees has been constructed for the first time, which demonstrates excellent coordination of water transport and salt rejection in interfacial evaporation desalination.

The investigation shows that nitrogen (N)-substituted π-conjugated semiconductor materials have improved optical and electronic performance and work efficiently in organic field-effect transistors (OFETs).

Benefiting from the superior optoelectronic properties and low-cost manufacturing techniques, mixed-halide wide bandgap (WBG) perovskite solar cells (PSCs) are currently considered as ideal top cells for fabricating multi-junction or tandem solar cells, which are designed to beyond the Shockley-Queisser (S-Q) limit of single-junction solar cells. However, the poor long-term operational stability of WBG PSCs limits their further employment and hinders the marketization of multi-junction or tandem solar cells. In this review, recent progresses on improving environmental stability of mixed-halide WBG PSCs through different strategies, including compositional engineering, additive engineering, interface engineering, and other strategies, are summarized. Then, the outlook and potential direction are discussed and explored to promote the further development of WBG PSCs and their applications in multi-junction or tandem solar cells.

Solvent residue is inevitable to occur in solution processed thin films, but its influence on the thin film quality has not been identified and addressed to date. Methylammonium acetate (MAAc) ionic liquid has recently been realized as an environmentally friendly solvent for solution processed perovskites. The specific high viscosity, low vapor pressure and strong association with perovskite precursor of the MAAc solvent is a double-edged sword, which endowed an advantageously ambient air operational and anti-solvent free perovskite deposition, but the MAAc is likely to be retained within the film and bring in detrimental effects on device performance of the corresponding solar cells. Herein, we reported a novel route to eliminate the residual solvent via a facial hydrochloric acid (HCl) annealing post-treatment (HAAP). In particular, chemical displacement reaction between the incorporated HCl and residual MAAc can be initiated to form volatile MACl and HAc, efficiently extracting MAAc residue. In the meanwhile, the stimulated mass transport via downward penetration and upward escape can trigger secondary perovskite growth with enlarged grain size and smoothened surface, leading to reduced defect state and improved interfacial contact intimacy, and also partial chloride ions are able to enter the crystal lattice to stabilize perovskite phase structure. As a result, a champion efficiency up to 20.78% originating from enhanced Voc was achieved, and more than 96% of its initial efficiency can be maintained after 1000 h shelf-storage.

The crucial component, bulky spacers, in two-dimensional Ruddlesden-Popper (2DRP) layered tin (Sn) perovskites are highly limited by halide ammonium salts, leading to the insufficient control of complex crystallization process due to the limited interaction between bulky spacers and 2DRP perovskite frameworks. Here, we report an ionic liquid-bulky spacer, butylammounium acetate (BAAcO), for constructing efficient and stable 2DRP Sn-based perovskite solar cells (PSCs). In contrast to the traditional halide ammonium bulky spacer, butylammounium iodide (BAI), the AcO−-functional group in BAAcO has a strong interaction with formamidine ions (FA+) and Sn2+. The inter-component interaction allows the formation of controllable intermediates for the favorable growth of smooth, dense, and highly oriented perovskite films. A PSC with power conversion efficiency of 10.36% (7.16% for BAI) is achieved, which is the highest report, along with improved stability with ∼90% retained after ∼600 h storage in N2 atmosphere without any encapsulation.

Perovskite synthesis out in the open Although methods have been developed that create the photoactive black perovskite phase of formamidinium lead iodide (α-FAPbI 3 ), these routes are temperature and humidity sensitive and less compatible with large-scale solar cell production. Hui et al. report an alternative route in which vertically aligned lead iodide thin films are grown from the ionic liquid methylamine formate. Nanoscale channels in the films lower the barrier to permeation of formamidinium iodide and enable transformation to α-FAPbI 3 , even at high humidity and room temperature. Solar cells made with these films have power conversion efficiencies as high as 24.1% that display high stability. Science , this issue p. 1359

The elucidation of intermolecular interactions for the systematic control of nucleation and crystallization is key to produce perovskite photovoltaics with superior performance. In this study, we a...

Low-dimensional Ruddlesden–Popper (LDRP) perovskites have attracted great attention due to their superior stabilities. However, these LDRP perovskites are required to grow vertically with respect to the substrates to enable efficient charge transport for highly efficient and stable perovskite solar cells (PSCs). Herein, we introduce a strategy to form a highly vertically oriented LDRP phase by introducing bromide (Br) into organic ammonium spacer of butylamine (BA) lead halide perovskites, i.e., (C4H9NH3)2MA4Pb5BrxI16−x. The LDRP perovskites with a small amount of Br (I–Br–I system with Br : PbI2 = 2 : 5 (molar ratio)) show the best abilities to form high-quality thin films and excellent vertical crystalline orientation, which facilitates charge transport and thus leads to highly efficient PSCs. As a result, a high champion PCE of 15.75% is achieved for the I–Br–I LDRP PSC compared to that of the pure iodine (I–I–I) device (12.15%). This work provides a new way to achieve efficient and stable LDRP PSCs.

Two-dimensional Ruddlesden–Popper layered metal-halide perovskites have attracted increasing attention for their desirable optoelectronic properties and improved stability compared to their three-dimensional counterparts. However, such perovskites typically consist of multiple quantum wells with a random well width distribution. Here, we report phase-pure quantum wells with a single well width by introducing molten salt spacer n-butylamine acetate, instead of the traditional halide spacer n-butylamine iodide. Due to the strong ionic coordination between n-butylamine acetate and the perovskite framework, a gel of a uniformly distributed intermediate phase can be formed. This allows phase-pure quantum well films with microscale vertically aligned grains to crystallize from their respective intermediate phases. The resultant solar cells achieve a power conversion efficiency of 16.25% and a high open voltage of 1.31 V. After keeping them in 65 ± 10% humidity for 4,680 h, under operation at 85 °C for 558 h, or continuous light illumination for 1,100 h, the cells show

Electron-transport-layer free perovskite solar cells (ETL-free PSCs) have attracted great attention due to their low cost and simple manufacturing process. However, an additional interface layer has to be introduced, and the currently achieved efficiency remains far from full-structure PSCs. Here, we report an in situ interface engineering strategy by the methylammonium acetate (MAAc) ionic liquid perovskite precursor. We found that a dipole layer was in situ constructed through the physical adsorption of the residual MAAc polar molecules on the indium tin oxide electrode, which is significantly different from the treatment by the interface layer in previous reports. This allows a decrease of the effective work function and enables in situ band bending in the perovskite semiconductor. The in situ band bending facilitates charge collection and hinders interfacial charge recombination, leading to ETL-free PSCs with a maximum power conversion efficiency of 21.08%, which is the highest report to date.

All-inorganic lead halide perovskites are promising candidates for optoelectronic applications. However, fundamental questions remain over the component interaction in the perovskite precursor solution due to the limitation of the most commonly used solvents of N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). Here, we report an interaction tailoring strategy for all-inorganic CsPbI3-x Brx perovskites by involving the ionic liquid solvent methylammonium acetate (MAAc). C=O shows strong interaction with lead (Pb2+ ) and N-H⋅⋅⋅I hydrogen bond formation is observed. The interactions stabilize the perovskite precursor solution and allow production of the high-quality perovskite films by retarding the crystallization. Without the necessity for antisolvent treatment, the one-step air-processing approach delivers photovoltaic cells regardless of humidity, with a high efficiency of 17.10 % along with long operation stability over 1500 h under continuous light illumination.

Skeletal muscle is the most abundant tissue in mammals, and myogenesis and differentiation require a series of regulatory factors such as microRNAs (miRNAs). In this study, we found that miR-103-3p was highly expressed in the skeletal muscle of mice, and the effects of miR-103-3p on skeletal muscle development were explored using myoblast C2C12 cells as a model. The results showed that miR-103-3p could significantly reduce myotube formation and restrain the differentiation of C2C12 cells. Additionally, miR-103-3p obviously prevented the production of autolysosomes and inhibited the autophagy of C2C12 cells. Moreover, bioinformatics prediction and dual-luciferase reporter assays confirmed that miR-103-3p could directly target the microtubule-associated protein 4 (MAP4) gene. The effects of MAP4 on the differentiation and autophagy of myoblasts were then elucidated. MAP4 promoted both the differentiation and autophagy of C2C12 cells, which was contrary to the role of miR-103-3p. Further research revealed that MAP4 colocalized with LC3 in C2C12 cell cytoplasm, and the immunoprecipitation assay showed that MAP4 interacted with autophagy marker LC3 to regulate the autophagy of C2C12 cells. Overall, these results indicated that miR-103-3p regulated the differentiation and autophagy of myoblasts by targeting MAP4. These findings enrich the understanding of the regulatory network of miRNAs involved in the myogenesis of skeletal muscle.

Xiang pig (XP) is one of the best-known indigenous pig breeds in China, which is characterized by its small body size, strong disease resistance, high adaptability, favorite meat quality, small litter sizes, and early sexual maturity. However, the genomic evidence that links these unique traits of XP is still poorly understood. To identify the genomic signatures of selection in XP, we performed whole-genome resequencing on 25 unrelated individual XPs. We obtained 876.70 Gb of raw data from the genomic libraries. The LD analysis showed that the lowest level of linkage disequilibrium was observed in Xiang pig. Comparative genomic analysis between XPs and other breeds including Tibetan, Meishan, Duroc and Landrace revealed 3062, 1228, 907 and 1519 selected regions, respectively. The genes identified in selected regions of XPs were associated with growth and development processes (IGF1R, PROP1, TBX19, STAC3, RLF, SELENOM, MSTN), immunity and disease resistance (ZCCHC2, SERPINB2, ADGRE5, CYP7B1, STAT6, IL2, CD80, RHBDD3, PIK3IP1), environmental adaptation (NR2E1, SERPINB8, SERPINB10, SLC26A7, MYO1A, SDR9C7, UVSSA, EXPH5, VEGFC, PDE1A), reproduction (CCNB2, TRPM6, EYA3, CYP7B1, LIMK2, RSPO1, ADAM32, SPAG16), meat quality traits (DECR1, EWSR1), and early sexual maturity (TAC3). Through the absolute allele frequency difference (ΔAF) analysis, we explored two population-specific missense mutations occurred in NR6A1 and LTBP2 genes, which well explained that the vertebrae numbers of Xiang pigs were less than that of the European pig breeds. Our results indicated that Xiang pigs were less affected by artificial selection than the European and Meishan pig breeds. The selected candidate genes were mainly involved in growth and development, disease resistance, reproduction, meat quality, and early sexual maturity. This study provided a list of functional candidate genes, as well as a number of genetic variants, which would provide insight into the molecular basis for the unique traits of Xiang pig.

Objective: To observe the behavioral changes of aged rats with hypercholesterolemia after inhalation of 1.0 MAC and 1.3MAC sevoflurane , the levels of hippocampal ApoE3, ApoE4 and Aβ1-42, as well as the changes of Aβ1-42 levels of optical density in hippocampal CA3 and CA1 regions, and to investigate the effects of different concentrations of sevoflurane on cognitive function in aged rats with hypercholesterolemia.Method: The 15-month-old male SD rats were fed a high-fat diet for 9 months. Rats successfully modeled (N=54) were randomly divided into three groups:control group (Con group, n=18), low concentration sevoflurane group ( Sev1.0 group, n=18), high concentration sevoflurane group (Sev1.3 group, n=18). Rats in the three groups inhaled aero mixed gas(1L/min O2+1L/min Air), 1.0MAC sevoflurane and 1.3MAC sevoflurane for 2h respectively.1 day, 30 days and 90 days after sevoflurane treatment were defined as T1, T30 and T90 experimental periods, respectively. In the three experiments, 6 rats were randomly selected from Con group, Sev1.0 group and Sev1.3 group to complete the behavior experiment in Morris water maze.Subsequently, the levels of ApoE3, ApoE4 and Aβ1-42 in the left hippocampus were detected by Western Blot.Expression of Aβ1-42 in the right hippocampal CA3 and CA1 regions of rats in each group was detected by frozen immunofluorescence assay.Result: 1. No behavioral changes were found in T1, T30 and T90 experiments.2. At T1 and T30, ApoE4 and Aβ1-42 in Sev1.3 group was significantly different from that in Con group. At T90, there was no difference in the levels of ApoE4 and Aβ1-42 between groups. ApoE3 expression was not statistically significant in the three experimental periods. 3. At T1 and T30, the average optical density of Aβ1-42 in CA3 and CA1 region, Sev1.3 group was significantly different from that in Con group. At T90, there was no significant difference between groups.Conclusion: After inhalation of 1.3MAC sevoflurane in aged SD hypercholesterolemia rats, the levels of ApoE4 and Aβ1-42 were increased in hippocampus at early and middle stage, and the average optical density of Aβ1-42 was increased in CA3 and CA1 area. The change trend of the two ones was consistent, but not enough to cause behavioral changes.

The mechanism of bacterial adaption to manganese-polluted environments was explored using 50 manganese-tolerant strains of bacteria isolated from soil of the largest manganese mine in China. Efficiency of manganese removal by the isolated strains was investigated using atomic absorption spectrophotometry. Bacillus safensis strain ST7 was the most effective manganese-oxidizing bacteria among the tested isolates, achieving up to 82% removal at a Mn(II) concentration of 2,200 mg/L. Bacteria-mediated manganese oxide precipitates and high motility were observed, and the growth of strain ST7 was inhibited while its biofilm formation was promoted by the presence of Mn(II). In addition, strain ST7 could grow in the presence of high concentrations of Al(III), Cr(VI), and Fe(III). Genome-wide analysis of the gene expression profile of strain ST7 using the RNA-seq method revealed that 2,580 genes were differently expressed under Mn(II) exposure, and there were more downregulated genes (n = 2,021) than upregulated genes (n = 559) induced by Mn stress. KAAS analysis indicated that these differently expressed genes were mainly enriched in material metabolisms, cellular processes, organism systems, and genetic and environmental information processing pathways. A total of twenty-six genes from the transcriptome of strain ST7 were involved in lignocellulosic degradation. Furthermore, after 15 genes were knocked out by homologous recombination technology, it was observed that the transporters, multicopper oxidase, and proteins involved in sporulation and flagellogenesis contributed to the removal of Mn(II) in strain ST7. In summary, B. safensis ST7 adapted to Mn exposure by changing its metabolism, upregulating cation transporters, inhibiting sporulation and flagellogenesis, and activating an alternative stress-related sigB pathway. This bacterial strain could potentially be used to restore soil polluted by multiple heavy metals and is a candidate to support the consolidated bioprocessing community.

Background Although lots of quantitative trait loci (QTLs) and genes present roles in litter size of some breeds, the information might not make it clear for the huge diversity of reproductive capability in pig breeds. To elucidate the inherent mechanisms of heterogeneity of reproductive capability in litter size of Xiang pig, we performed transcriptome analysis for the expression profile in ovaries using RNA-seq method. Results We identified 1,419 up-regulated and 1,376 down-regulated genes in Xiang pigs with large litter size. Among them, 1,010 differentially expressed genes (DEGs) were differently spliced between two groups with large or small litter sizes. Based on GO and KEGG analysis, numerous members of genes were gathered in ovarian steroidogenesis, steroid biosynthesis, oocyte maturation and reproduction processes. Conclusions Combined with gene biological function, twelve genes were found out that might be related with the reproductive capability of Xiang pig, of which, eleven genes were recognized as hub genes. These genes may play a role in promoting litter size by elevating steroid and peptide hormones supply through the ovary and facilitating the processes of ovulation and in vivo fertilization.

Atomic valence state regulation is an advantageous approach for improving photocatalytic efficiency and product selectivity. However, it is difficult to precisely control the ratio of the different valence states on the surface and the relationship between the surface valence change and catalytic efficiency in the photocatalytic reaction process is unclear. Herein, CeVO4 ultrathin nanosheets were fabricated by one-step solvothermal method with ethanolamine (MEA) as the structure-directing agent. The ratio of the concentrations of intrinsic Ce4+ and Ce3+ ions is precisely modulated from 19.82:100 to 13.33:100 changed by the volume of MEA added without morphology modification. The photocatalytic efficiency increases as the concentrations of intrinsic Ce4+ and Ce3+ ions decrease and CV3 (prepared with 3 mL of MEA) shows the highest CO generation rate approximately 6 and 14 times larger than CV (prepared without MEA) and CV1 (prepared with 1 mL of MEA), respectively, in the photocatalytic CO2 reduction. Interestingly, about 6.8% photo-induced Ce4+ ions were generated on the surface of the catalysts during the photocatalytic CO2 reduction without any phase and morphology changes for CV3. The photocatalytic reaction mechanism is proposed considering the intrinsic and photo-induced Ce4+ ions to obtain efficient photocatalysts.

Valinomycin, a cyclic peptide, was incorporated into a biomimetic lipid membrane tethered to the surface of a gold (111) electrode. Electrochemical impedance spectroscopy was used to study the ionophore properties of the peptide, and polarization modulation infrared reflection absorption spectroscopy was employed to determine the conformation and orientation of valinomycin in the membrane. The combination of these two techniques provided unique information about the ionophore mechanism where valinomycin transports ions across the membrane by creating a complex with potassium ions and forming an ion pair with a counter anion. The ion pair resides within the hydrophobic fragment of the membrane and adopts a small angle of ∼22° with respect to the surface normal. This novel study provides new insights explaining the valinomycin ion transport mechanism in model biological membranes.

To gain a better knowledge of structural variations (SVs) in Xiang pig, we used next-generation sequencing to analyze the Xiang pigs with larger (XL) or smaller litter sizes (XS). Our analysis yielded 28,040 putative SVs in the Xiang pig. These SVs distributed throughout all of chromosomes. Some functional regions including exons and untranslated regions were less varied than introns and intergenic regions. We detected 4637 and 4119 specific SVs, which contained 1697 and 1582 genes in XL and XS group, respectively. These genes were mainly enriched in the well-known pathways involved in development and reproduction processes. Population validation was carried out on 50 SVs candidates using PCR method in 144 Xiang pig crowds. All of 50 SVs were confirmed by PCR method and 14 SVs were associated with the litter size of Xiang pigs. These results may be helpful for the elucidation of growth and reproduction regulation in Xiang pig.

In this paper, the electrochemiluminescence (ECL) behavior of a hole-transport polymer, poly [9,9-bis(3'-(N,N-dimethylamino) propyl)-2,7-fluorene]-alt-2,7-(9,9-dio ctylfluorene)] (PFN) was examined with the purpose of finding a novel organic ECL emitter. It was found that the PFN exhibits self-electrochemiluminescence (self-ECL) without any exogenous co-reactants. Quite different from the traditional ECL, the addition of tripropyl amine (TPA) quenched the self-ECL of PFN. PFN ECL intensity reaches a peak during electrochemical oxidation process due to the superposition of self-enhanced ECL, and aggregation quenching of excited state by PFN excimer formation. Aluminum tris(8-quinolinolate) (AlQ3) doped with PFN recovers luminescence intensity with restraining quenching effect via ECL resonance energy transfer from PFN to AlQ3, giving rise to a stable luminescence signal, and hence sensory detection of nitroaromatics. The limits of detections for nitroaromatics can reach down to a level of 10−22 M. This work sets the stage for a novel organic polymer-based ECL emitter without using any toxic exogenous co-reactant, and presents a practical avenue for a prototype of realising sensory detection through signal stabilization via energy resonance energy transfer (ERET).

A new kind of organic charge transport nanomolecule, 4H-cyclopenta[2,1-b:3,4-b′]dithiophene-based windmill-shaped nanogrid called WG-CPDT, and its corresponding derivatives substituted by ethynyl, cyano, fluorine and methyl groups at 1-position of CPDT moiety, was designed and studied theoretically. The density functional theory (DFT) was then employed to investigate the molecular structures and electronic properties such as molecular orbitals, ionization potentials (IPs), electron affinities (EAs), reorganization energies (λ). Furthermore, the noncovalent interaction analysis and the normal mode analysis were utilized to estimate the intramolecular weak interactions and the contributions of each vibrational modes to reorganization energies, respectively. The results indicate that WG-CPDT possesses a small reorganization energy in the electron transfer process, and that WG-CPDT is a kind of potential organic electron transport material. This is especially notable when WG-CPDT is modified with cyano on the 1-position of the CPDT moiety and the electron reorganization energies decrease to 0.099 eV. In addition, the delocalization of LUMO near C(sp3) position is consistent with the S⋯π and C H⋯π weak interactions, which favors good electron transport properties. This work provides new insights into a type of bulky macrocycle in charge transport materials.

The lower charge mobility of organic semiconductors relative to that of inorganic semiconductors is a thorny problem that still has not been resolved. Here, a new type of arrangement of grid-shaped organic semiconductors with extremely low values of internal reorganization energies (IREs) for both hole (0.056 eV) and electron (0.078 eV) transfer processes has been designed and investigated by density functional theory (DFT) calculations. The structural, thermodynamic and electronic properties of grid spirofluorene (GSF) consisting of four spirobifluorenes have been discussed thoroughly. Our analyses of these unique grid structures indicate that they possess a stringent structure and very weak ring strain energy, and may be easily synthesized in the laboratory. Interestingly, GSF1, GSF2, and GSF9 possess both small hole and lower electron transfer reorganization energies (

Compared to the conventional three dimensional (3D) organic–inorganic halide perovskites, two dimensional (2D) Ruddlesden–Popper (RP) perovskites have attracted extensive attention in photovoltaics in recent years due to their excellent stability without sacrificing too much efficiency. The remarkable improvement in stability and rapid rise in efficiency are attributed to the unique properties caused by the quantum well structure due to the introduction of bulky organic ammonium spacers. In this perspective, we distill the outstanding features of the current state-of-the-art 2DRP perovskites, including enhanced stability, tunable exciton binding energy, out-of-plane oriented growth, and phase distribution. We also briefly discuss the potential technological development of RP perovskites as emerging semiconductor photovoltaic materials. The current challenging issues and future perspectives are also provided.

Rapid progress of digital communications in the Big Data and Internet of things has stimulated the exploration of next-generation data storage devices. Among various candidates, resistive switching (RS) memory devices and artificial synapses are in the spotlight due to their low power consumption, downscaling potential, and fast operation speed. The exceptional electronic and mechanical characteristics of metal halide perovskites (MHPs) have greatly promoted their application in nonvolatile high density, low-cost, and flexible memory devices. Here, we distill the current state-of-the-art and highlight recent advances of MHP based RS memory devices and artificial synapses. The general structure and characteristics of RS memory devices are first introduced. Afterwards we discuss the excellent memory behaviors accompanied by detailed working mechanisms. Finally, the current challenges and future development prospects are also discussed. This review article is expected to pave the way in the rational design of MHP based memory devices and artificial synapses with unprecedented performance improvement.

Radio frequency fingerprint technology is of great significance to the security of the Internet of Things system. When the signal uses I/Q modulation, the demodulated signal can be drawn on a two-dimensional plane, that is, constellation diagram. Slight differences in the manufacture and use of transmitters can cause the constellation to shift. Differential Constellation Trace Figure (DCTF) with device characteristics can be generated by special differential processing of demodulation signal. In this paper, the DCTFs of QPSK signal are used as radio frequency fingerprints. Radio frequency fingerprints are classified using MobileNet, a lightweight network that can be used for mobile and embedded devices. In the final simulation experiment, the accuracy of MobileNet V2 and MobileNet V3 are both over 95% when SNR is low. Comparing with the accuracy of CNN, MobileNet V2 and MobileNet V3 are better choices.

Micro RNAs (miRNAs) are major players in cellular responses to xenobiotic compounds and toxins. However, their functions in organophosphate-induced cytotoxicity remain unclear. This study investigated the involvement of miR-96-5p in the non-cholinergic toxicity of malathion in normal human kidney cells (HK-2 cells). Malathion decreased HK-2 cell viability and the expression of miR-96-5p in a dose- and time-dependent manner. In addition, transfection with miR-96-5p mimics attenuated malathion-induced HK-2 cell apoptosis, whereas transfection with a miR-96-5p inhibitor increased HK-2 cell apoptosis. Luciferase assays indicated that miR-96-5p could bind directly to the 3'-untranslated region of DDIT3, a well-known marker of endoplasmic reticulum stress. Further analyses of the expression of apoptosis-related genes and proteins indicated that miR-96-5p may function to reduce malathion-induced HK-2 cell apoptosis via regulation of the DDIT3/B-cell lymphoma (BCL)-2/caspase-3 signaling pathway. In summary, the results of the present study indicate that miR-96-5p protects HK-2 cells from malathion-induced ER stress-dependent apoptosis by targeting DDIT3.

Recently, the power conversion efficiency (PCE) of perovskite solar cells (PSC) based on organic-inorganic hybrid Pb halide perovskites has reached 25.2 %. However, the toxicity of Pb has still been a main concern for the large-scale commercialization of Pb-based PSCs. Efforts have been made during the past few years to seek eco-friendly Pb-free perovskites, and it is a growing consensus that Sn is the best choice as Pb alternative over any other Pb-free metal elements. Among Sn-based perovskites, all-inorganic cells are promising candidates for PSCs owing to their more suitable bandgap, better stability, and higher charge mobility compared to the organic-inorganic hybrid counterparts. However, the poor phase stability of all-inorganic Sn-based perovskites (AISPs) and low PCE of their PSCs are most challenging in the field at present. Herein, recent developments on PSCs based on AISPs, including CsSnX3 and Cs2 SnX6 (X=Br, I), are comprehensively reviewed. Primarily, the intrinsic characteristics of the two AISPs are overviewed, including crystallographic property, band structure, charge carrier property, and defect property. Sequentially, state-of-the-art progress, regarding the photovoltaic application of AISPs as light absorber, is summarized. At last, current challenges and future opportunities of AISP-based PSCs are also discussed.

Alternative splicing (AS) is an important mechanism for controlling gene expression, which regulates multiple biological processes in higher organisms. Chinese indigenous Xiang pig has distinctive biological characteristics, such as small size, early sexual maturity, lower litter size and not very clear exhibition of estrous behaviors. To further understand how AS responds to estrous cycles in Xiang pig, the genome-wide analysis of AS events was performed by RNA-seq method in Xiang pig ovaries at diestrous and estrous. Using ASprofile program, we analyzed twelve basic AS events in Xiang pig ovaries and identified 68,775 AS events in 15,142 genes from diestrous ovaries and 69,493 AS events in 15,291 genes from the estrous ovaries with average 4.54 splicing events. 94.4-95.5% of expressed genes underwent alternative splicing in this tissues. The frequencies of AS events were similar to each other at diestrous and estrous. Transcription start site (TSS) was the predominant type of AS events, followed by transcription terminal site (TTS), and skipped exon (SKIP). The remaining type of AS events, e.g., intron retention (IR) and alternative exon ends (AE), showed the lower frequencies. Further comparison analysis of gene expression indicated that 4,433 genes had at least one splice variant differentially expressed during estrous, whereas only 2,382 of them were differentially expressed at gene level. Numerous genes involved in gonad development and hormone metabolism were differentially regulated through AS. Twelve genes with different types of alternatively splicing were validated by using RT-PCR method. The GO annotation and KEGG pathway analysis clearly revealed that a lot of DEGs (differentially expressed genes) and DSGs (differentially spliced genes) were involved in follicular development and ovarian steroid biosynthesis. A large number of DSGs, although not differentially expressed, were enriched in circadian rhythm and several signaling pathways. These pathways potentially regulated the female animal reproductive function in gene and/or AS level. Our results suggested that alternative splicing play an essential role in regulation of gene expression in female pigs during estrous. Numerous genes involved in gonad development, hormone metabolism, circadian rhythm were differentially regulated through alternative splicing.

To further understand the role of microRNA (miRNA) during testicular development, we constructed four small RNA libraries from the testes of the Chinese indigenous Xiang pig at four different ages, which were sequenced using high-throughput Solexa deep sequencing methods. It yielded over 23 million high-quality reads and 1,342,579 unique sequences. At two and three months of age, the proportion which represented miRNAs was the most abundant class of small RNAs, but it was gradually replaced by the category that represented piRNAs in adult testes. We identified 543 known and homologous conserved porcine miRNAs and 49 potential novel miRNAs. There were 306 known miRNAs which were co-expressed in four libraries. Six miRNAs and three potential novel miRNAs were validated in testes and sperms of Xiang pig by RT-qPCR method. Many clusters of mature miRNA variants were observed, in which let-7 family was the most abundant one. After comparison among libraries, 204 miRNAs were identified as being differentially expressed and likely involved in the development and spermatogenesis of pig testes. This work presented a general genome-wide expression profile of the testes-expressed small RNAs in different ages of pig testes. Our results suggested that miRNAs performed a role in the regulation of mRNAs in puberty pig testes while piRNAs likely functioned mainly in sexually mature pig testes.

The aim of the study was to investigate the SINE polymorphism in Xiang, Kele, Qianbei black, Jiangkouluobo, Large White, and Duroc pig breeds. The PCR based detection method was conducted to identify the short interspersed nuclear element (SINE) polymorphism in the PDIA4 gene. There were greater frequencies of the SINE-/- genotypes in Xiang pigs (55.9%) as compared with other pig breed groups. There was an association between this 275 bp SINE polymorphism and litter size (P = 0.003). The homozygous SINE+/+ genotype of the PDIA4 gene had a 1.45-piglets larger litter sizes compared to those with the homozygous SINE-/- genotype. Furthermore, there were assessments of mRNA and protein abundances as a result of PDIA4 gene expression in the ovaries of Xiang pigs for the three different SINE genotypes, and the results indicated that relative abundances of PDIA4 mRNA and protein was greater for the SINE-/- and SINE-/+ genotypes compared with the SINE+/+ genotype (P 0.05). These findings suggested that the 275 bp SINE polymorphism might change the expression of the PDIA4 gene and could be used as a candidate DNA marker for the selection for litter size in Xiang pigs.

Copy number variation (CNV) is a major proportion of genetic variation, which changes the gene structure and dosage and affects gene expression and function. To validate the presence and the function of CNV in pig, we used real-time quantitative polymerase chain reaction (qPCR) method to validate a 496 kb CNV region comprising MTHFSD gene on chromosome 6 of Xiang pig detected by single nucleotide polymorphism (SNP) array. Then we investigated the distribution of the MTHFSD CNV in a total of 545 pigs in four breeds. About 46.2% and 32.7% individuals in the four pig breeds were detected to be types of loss and gain of MTHFSD locus. The relative copy numbers of MTHFSD gene showed the largest variation range (0-55 copies) in the Xiang pig population. The copy numbers of MTHFSD gene presented the positive correlations with the transcript level of MTHFSD gene in adult ovaries. Statistical analysis indicated that CNVs of MTHFSD gene was significantly changed the litter size traits of Xiang pigs, and the individuals with CNV gain showed more litter size than the CNV loss pigs. We have reasons to believe that the MTHFSD as RNA-binding protein play an important role in pig reproduction as a result of regulating MTHFS mRNA metabolism.