Search

We report a genome-wide association study of facial features in >6000 Latin Americans based on automatic landmarking of 2D portraits and testing for association with inter-landmark distances. We detected significant associations (P-value <5 × 10−8) at 42 genome regions, nine of which have been previously reported. In follow-up analyses, 26 of the 33 novel regions replicate in East Asians, Europeans, or Africans, and one mouse homologous region influences craniofacial morphology in mice. The novel region in 1q32.3 shows introgression from Neanderthals and we find that the introgressed tract increases nasal height (consistent with the differentiation between Neanderthals and modern humans). Novel regions include candidate genes and genome regulatory elements previously implicated in craniofacial development, and show preferential transcription in cranial neural crest cells. The automated approach used here should simplify the collection of large study samples from across the world, facilitating a cosmopolitan characterization of the genetics of facial features. A genome-wide association study and fully automatic landmarking approach on frontal 2D face photographs of >6000 Latin Americans identifies novel genomic regions influencing facial features and implicates Neanderthal introgression in nasal shape. [ABSTRACT FROM AUTHOR]

• A green ionic liquid was introduced as solvent to prepare BDA-based DJ quasi-2D PSCs. • Defect/interface-induced recombination loss in DJ PSCs was significantly suppressed. • The optimal device showed an impressive PCE of 18.76 % with a remarkable V oc of 1.24 V. • Loss was quantified by photovoltaic parameters relative to DB limit and QFLS values. Dion-Jacobson (DJ) quasi-two-dimensional (quasi-2D) perovskites have emerged as a potential photovoltaic material due to their versatile n-layer variation and superior stable structure. However, compared to their three-dimensional counterparts, the power conversion efficiency (PCE) of quasi-2D perovskite solar cells (PSCs) reported to date still lags behind the detailed balance (DB) limit for single-junction PSCs, which derives from the presence of non-radiative recombination loss. Herein, we demonstrated that the defect/interface-induced recombination loss in DJ quasi-2D PSCs could be significantly suppressed by introducing a green ionic liquid methylammonium acetate (MAAc) into (BDA)(MA) 4 Pb 5 I 16 (n = 5) (BDA, 1,4-butanediamine) perovskite precursor. Both the film quality of 2D perovskites and the interfacial property of perovskite/charge transporting layer (CTL) were improved after introducing MAAc in precursor solution. Correspondingly, a champion PCE of 18.76 % with a remarkable open-circuit voltage (V oc) of 1.24 V was achieved. Through the quantitative loss analysis, which involved the calculation of photovoltaic parameters relative to DB limit and quasi-Fermi level splitting values, the improvement of PCE and V oc by introducing MAAc was mainly attributed to the reduction of defects in perovskite films and at perovskite/CTL interfaces, and the optimization of interfacial energy-level alignment. The present work provides a green solvent strategy for improving the performance of quasi-2D PSCs, and offers an insight into the fundamental physics of non-radiative recombination loss tailored by ionic liquid. [ABSTRACT FROM AUTHOR]

A new symmetric compound 3,5-bis(3-amine-4H-1,2,4-triazole)-1H-pyrazole and a series of corresponding energetic salts 5–9 were synthesized. All the new compounds were fully characterized by spectroscopy (IR, NMR, and elemental) analyses and differential scanning calorimetry (DSC). Compound 6 was further investigated by X-ray crystal-structure analysis. Various performance tests of all the compounds, such as density, thermal behavior, mechanical sensitivity and detonation property, were tested. All the target compounds showed relatively positive calculated heat of formation (24.9 to 2396.4 kJ mol−1), good mechanical sensitivity (IS > 24 J, FS > 280 N) and acceptable detonation property (D > 7400 m s−1, P > 19.5 GPa). In particular, energetic salt 9 exhibits prominent detonation property (D > 8964 m s−1, P > 37.1 GPa) and excellent sensitivity (IS > 40 J, FS > 360 N), which show its potential application prospects as a new high energy insensitive material. [ABSTRACT FROM AUTHOR]

The intramolecular cyclization reaction of picrylhydrazone into an indazole derivative was systematically studied. The optimized conditions, mechanism and the generality of the cyclization reaction from picrylhydrazone to indazole were investigated. Picrylhydrazones 1a–6a and indazole derivatives 1b and 3b–7b were synthesized through a one-step reaction and the crystal structures of 2a, 4a and 5b were characterized by single crystal X-ray diffraction analysis. Among all the compounds, the indazole derivatives exhibit an increase of 24–341 m s−1 (0.3–4.3%), 0.6–3.1 GPa (2.2–14.3%) and 9–82 °C (5.0–44.0%) in detonation performance and thermal stability as well as a decrease of 4–10 J (15.4–33.3%) and 50–120 N (16.1–50.0%) in mechanical sensitivity to impact and friction compared with picrylhydrazones. Furthermore, the structure–property relationship was demonstrated by a combination of fingerprint plots, Hirshfeld surfaces and explosive properties. All those results demonstrated that this study can enrich the future prospects of the design of energetic materials. [ABSTRACT FROM AUTHOR]

Abstract It is considered that alkaline elements (such as Na, K, Rb) introduced through post-deposition treatment are able to modify the near-surface region of Cu(InGa)Se 2 thin films. However, research on the effects of Ca element on properties of Cu(InGa)Se 2 thin films is hardly reported. In this paper, Cu(InGa)Se 2 thin films were prepared on quartz glass by e-beam evaporation via two-step process. Study of structural property showed that a certain amount of CaF 2 through post-deposition treatment was beneficial to the uniform composition distribution of Cu(InGa)Se 2 thin films. Near-surface region of Cu(InGa)Se 2 thin films was more Cu-depleted by increasing introduced amount of Ca element. It was inferred that Ca diffused into the Cu(InGa)Se 2 thin films substituted the In sites as Ca In so as to increase the carrier concentration. By calculation, the spike barrier of CdS/Cu(InGa)Se 2 heterojunction was shown to decrease with increased thickness of CaF 2 layers. As a result, Cu(InGa)Se 2 solar cell subjected to 20 nm CaF 2 post-deposition treatment, which possessed higher fill factor, open circuit voltage and short circuit current density, achieved the optimal power conversion efficiency. An efficiency of Cu(InGa)Se 2 solar cell was enhanced by 2.9% after 20 nm CaF 2 post-deposition treatment. Highlights • Well crystallized CIGS thin films were prepared on quartz glass via two-step process. • Ga graded distribution in the films was alleviated after CaF 2 PDT. • Near-surface region of CIGS thin films was more Cu-poor by increasing amount of Ca. • An efficiency of CIGS solar cell was enhanced by 2.9% through 20 nm CaF 2 PDT. [ABSTRACT FROM AUTHOR]

To investigate the effects of Sb doping on the structural and electrical properties of Cu(InGa)Se 2 (CIGS) thin films and solar cells, CIGS thin films, prepared by e-beam evaporation on soda-lime glass, were doped with lower and upper Sb layers in the precursor stacks respectively. Change of structure and introduction of stress were observed in the CIGS thin films with upper Sb layer in stack through XRD and Raman measurement. Both crystalline quality and compactness of CIGS thin films were improved by the doping of upper Sb layer in stack and the CIGS thin film showed an optimal structural property with 20 nm Sb layer. Movement of Fermi level of the surface of CIGS thin film after doping of upper Sb layer in stack and electrons transfer between Cu/Cu + redox couple and CIGS thin films, which provided probability for the substitution of Sb for Cu sites at the surface of CIGS thin films, were proposed to explain the migration of Cu from the surface to the bulk of CIGS thin films. The larger barrier at the CIGS/CdS interface after doping of upper Sb layer in stack made contribution to the increase of V OC of CIGS solar cells. The efficiency of CIGS solar cell was improved from 3.3% to 7.2% after doping with 20 nm upper Sb. Compared to the CIGS solar cell with lower Sb layer in stack, in which an additional Cu 2-x Se phase was found, the CIGS solar cell with upper Sb layer in stack possessed a higher efficiency. [ABSTRACT FROM AUTHOR]

• A novel bio-based UV-curable coating was prepared from epoxidized vegetable oils. • A facile approach to preparing bio-based organic-inorganic hybrid UV-curable coatings. • The hybrid UV-cured films showed excellent hydrophobic and self-cleaning property. • The UV-curable hydrophobic coating showed great potential for practical applications. Bio-based coatings gradually become an ideal substitution for the non-renewable petroleum-based coatings due to the features of environmental friendliness and low cost, and the preparation of high-performance bio-based coatings via a facile method is highly desirable. Herein, bio-based organic-inorganic hybrid UV-curable coatings with self-cleaning property were prepared in a solvent-free one-pot method. In this coating system, synthesized epoxidized castor oil (ECO) was used as a coating precursor, glycidyl methacrylate (GMA) and 3-glycidoxypropyltrimethoxysilane (GPTMS) were used as reactive diluents, and triarylsulfonium salt (TAS) was used as an effective cationic photoinitiator. Besides, commercial epoxidized soybean oil (ESO) was employed as another coating precursor to compare with ECO. The chemical structure of the synthesized ECO was confirmed by 1H NMR and FT-IR. The occurrence of double bond radical copolymerization, epoxy ring-opening copolymerization and trialkoxysilyl sol-gel reaction in the cured films was proved via ATR-FTIR. The properties of the films cured with different GPTMS contents were investigated. Dynamic mechanical analysis (DMA) results revealed that EC films showed better performance than ES films, and the addition of GPTMS reduced the glass transition temperature (T g) and crosslinking density (ν e) of the cured films. However, the addition of GPTMS increased the peak temperature (T p) and char yield (W char) of the cured films, indicative of the enhancement in thermal stability. SEM results indicated that the incorporation of GPTMS in the cured films facilitated the obtainment of a smooth surface. Furthermore, all of EC films were hydrophobic, and they also exhibited self-cleaning property. In addition, they showed excellent hardness and acid resistance. Therefore, this study provided a facile approach to preparing bio-based organic-inorganic hybrid UV-curable films with self-cleaning property, and the high performances of these cured films made them potential for practical applications. [ABSTRACT FROM AUTHOR]

• CIGS solar cells were fabricated on ultrathin glass. • Potassium was doped by a simple method during the post-selenization process. • The efficiency of solar cell got enhanced by 2.5% after potassium incorporation. • It was first revealed that K doping retarded the property degradation of solar cell. Flexible Cu(InGa)Se 2 solar cells fabricated on metal foils and plastics have achieved high conversion efficiency so far. However, metal impurities and low temperature tolerance hinder them from further considerable development. Here, 150 μm-thick ultrathin glass with desirable advantages was applied as substrate for Cu(InGa)Se 2 solar cell. Potassium element was doped by a simple method during the post-selenization process. The results showed that the KInSe 2 phase existed in K-doped Cu(InGa)Se 2 films. The K-doped CIGS films were more compact than the pristine one due to the fact that K incorporated in films could form quasi-liquid alkali-metal-Se compounds and improve the compactness of films. K-incorporated CIGS films exhibited enhanced p-type conductivity and different surface energy level. Consequently, K-doped Cu(InGa)Se 2 solar cell achieved an optimal efficiency of 8.3%, which was relatively 43% higher than that of pristine solar cell. Investigation of performance and stability of solar cells manifested that the K incorporation retarded the performance degradation of device during cyclic bending. [ABSTRACT FROM AUTHOR]

• Cd-free CIGS solar cells with a-Si buffer layers are fabricated for the first time. • The conduction band alignment of CIGS/a-Si is a favorable spike. • SCAPS predicts enhanced efficiency by optimization of bandgap and E CB of CIGS films. • The efficiency of cell with modified CIGS film is relatively improved by over 30%. CdS, In 2 S 3 and ZnO-based materials are typically adopted as buffer layers in high efficiency CIGS solar cells. However, the drawbacks involved toxicity, complicated synthesis process and environmental damage of aforementioned materials would someday limit the development themselves. Here, for the first time, eco-friendly and low-cost a-Si thin films prepared by e-beam evaporation were used as buffer layers in CIGS solar cells. Thickness of a-Si films was changed to optimize the performance of CIGS solar cells through investigating their optical, structural and electrical properties. It revealed that the conduction band alignment of CIGS and a-Si is a favorable spike and a 60 nm a-Si film is optimal for CIGS/a-Si interface properties. Following the SCAPS simulation, bandgaps and conduction band energy level of CIGS films were facilely modulated through altering the Ga/(Ga + In) ratios. The conversion efficiency of solar cell with modified CIGS film was relatively improved by over 30% compared to the pristine one. The present work provides a new and eco-friendly strategy for fabrication of CIGS solar cells and expands the application of a-Si thin films as buffer layers for solar cells. [ABSTRACT FROM AUTHOR]

Amorphous carbon (a-C) films were synthesized on quartz substrates through a hot-filament chemical vapor deposition (HFCVD) method. Effect of filament temperature on the thickness, structural, morphological and electrical properties of a-C films was investigated. Both the crystalline quality and sp 2 content of a-C films increased by raising the filament temperature from 1800 °C to 2000 °C. Sharp increase of the surface roughness was observed as the filament temperature increased from 2000 °C to 2100 °C. The a-C films deposited at the filament temperature of 2000 °C with a high growth rate of 35 nm/min exhibited the optimal quality with a small roughness of 0.546 nm and a low resistivity of 1.67 × 10 −2  Ω·cm. These results indicated that HFCVD is a good method to prepare conductive a-C films rapidly and effectively. [ABSTRACT FROM AUTHOR]

Complex pollutants are discharging and accumulating in rivers and oceans, requiring a coupled strategy to resolve pollutants efficiently. A novel method is proposed to treat multiple pollutants with C,N co-doped TiO2 hollow nanofibers coated stainless steel meshes which can realize efficient oil/water separation and visible light-drove dyes photodegradation. The poly(divinylbenzene-co-vinylbenzene chloride), P(DVB-co-VBC), nanofibers are generated by precipitate cationic polymerization on the mesh framework, following with quaternization by triethylamine for N doping. Then, TiO2 is coated on the polymeric nanofibers via in-situ sol–gel process of tetrabutyl titanate. The functional mesh coated with C,N co-doped TiO2 hollow nanofibers is obtained after calcination under nitrogen atmosphere. The resultant mesh demonstrates superhydrophilic/underwater superoleophobic property which is promising in oil/water separation. More importantly, the C,N co-doped TiO2 hollow nanofibers endow the mesh with high photodegradation ability to dyes under visible light. This work draws an affordable but high-performance multifunctional mesh for potential applications in wastewater treatment. [ABSTRACT FROM AUTHOR]

Although the photovoltaic performance of perovskite solar cells (PSCs) has reached the commercial standards, the unsatisfactory stability limits their further application. Hydrophobic interface and encapsulation can block the damage of water and oxygen, while the instability induced by intrinsic residual strain remains inevitable. Here, the residual strain in a two‐dimensional (2D) Ruddlesden–Popper (RP) perovskite film is investigated by X‐ray diffraction and atomic force microscopy. It's found that the spacer cations contribute to the residual strain even though they are not in the inorganic cages. Benefited from strain relaxation, the film quality is improved, leading to suppressed recombination, promoted charge transport and enhanced efficiency. More significantly, the strain‐released devices maintain 86 % of the initial efficiency after being kept in air with 85 % relative humidity (RH) for 1080 h, 82 % under maximum power point (MPP) tracking at 50 °C for 804 h and 86 % after continuous heating at 85 °C for 1080 h. [ABSTRACT FROM AUTHOR]

Although the photovoltaic performance of perovskite solar cells (PSCs) has reached the commercial standards, the unsatisfactory stability limits their further application. Hydrophobic interface and encapsulation can block the damage of water and oxygen, while the instability induced by intrinsic residual strain remains inevitable. Here, the residual strain in a two‐dimensional (2D) Ruddlesden–Popper (RP) perovskite film is investigated by X‐ray diffraction and atomic force microscopy. It's found that the spacer cations contribute to the residual strain even though they are not in the inorganic cages. Benefited from strain relaxation, the film quality is improved, leading to suppressed recombination, promoted charge transport and enhanced efficiency. More significantly, the strain‐released devices maintain 86 % of the initial efficiency after being kept in air with 85 % relative humidity (RH) for 1080 h, 82 % under maximum power point (MPP) tracking at 50 °C for 804 h and 86 % after continuous heating at 85 °C for 1080 h. [ABSTRACT FROM AUTHOR]

In this paper, Cu 2 (Fe x Zn 1 − x )SnS 4 nanocrystals were synthesized by a microwave irradiation assisted solvothermal method. The properties of Cu 2 (Fe x Zn 1 − x )SnS 4 nanocrystals were studied by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, and UV–vis spectroscopy. The results showed that as-synthesized Cu 2 (Fe x Zn 1 − x )SnS 4 nanocrystals had a single phase and stoichiometric composition. The average crystalline size increased with increasing x . Moreover, the band gaps of Cu 2 (Fe x Zn 1 − x )SnS 4 nanocrystals decreased with increasing x . [ABSTRACT FROM AUTHOR]

Epithelial homeostasis is fundamental for the physiological functions of colon tissue. Dysregulation of colon epithelial structure leads to abnormal immune responses and diseases such as inflammatory bowel disease. In this work we found long non-coding RNA DANCR was a novel regulator to colon epithelial homeostasis. Silencing DANCR resulted in decreased expression of epithelial barrier proteins and enhanced susceptibility to TNFα stimulation, which was accompanied by hyperactivation of the NF-κB pathway. Mechanistical studies revealed DANCR modulated the expression of a protein methyltransferase SET7 to suppress responses to TNFα, as well as the activity of NF-κB pathway. In summary, DANCR regulated colon epithelial homeostasis through modulating the TNFα/NF-κB axis. These findings cast light on the discovery of novel regulators to colon epithelial homeostasis and added new evidence to the physiological functions of DANCR. • DANCR is essential for maintaining colon epithelial homeostasis. • DANCR suppresses the TNFα/NF-κB pathway to regulate epithelial homeostasis. • SET7 mediates the regulation to the TNFα/NF-κB pathway by DANCR. [ABSTRACT FROM AUTHOR]

CZTSSe thin films based on three-layer precursors with Cu-poor and Zn-rich in top and bottom layer while stoichiometric in middle layer were prepared. Compared with CZTSSe thin film obtained from a stoichiometric single layer precursor, the crystallization of thin film from a three-layer precursor got enhanced. Element distribution and growth nuclei position in precursor played an important role on CZTSSe thin film formation and solar cell performance. The conversion efficiency of CZTSSe solar cell from a three-layer precursor attained an increase of 3.54% over that from a single layer precursor. [ABSTRACT FROM AUTHOR]