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Planar cell polarity (PCP), a process of coordinated alignment of cell polarity across the tissue plane, may contribute to the repair of renal tubules after kidney injury. Intu is a key effector protein of PCP. Herein, we have established conditional knockout (KO) mouse models that ablate Intu specifically from kidney tubules (Intu KO). Intu KO mice and wild-type littermates were subjected to unilateral renal ischemia/reperfusion injury (IRI) or unilateral ureteral obstruction. Kidney repair was evaluated by histologic, biochemical, and immunohistochemical analyses. In vitro, scratch wound healing was examined in Intu-knockdown and control renal tubular cells. It was found that ablation of Intu in renal tubules delayed kidney repair and ameliorated renal fibrosis after renal IRI. Intu KO mice also had less renal fibrosis during unilateral ureteral obstruction. Mechanistically, Intu KO kidneys had less senescence but higher levels of cell proliferation and apoptosis during kidney repair after renal IRI. In vitro, Intu knockdown suppressed scratch wound healing in renal tubular cells, accompanied by the abnormality of centrosome orientation. Together, the results provide the first evidence for the involvement of PCP in tubular repair after kidney injury, shedding light on new strategies for improving kidney repair and recovery.

This paper presents our theoretical study of tandem perovskite solar cells, simulated using a solar cell capacitance one-dimensional tool. The simulation reveals that the efficiency reaches 30.88% while combining Methylammonium Lead Iodide (MAPbI3) and Methylammonium Tin Iodide (MASnI3) as an absorber. The present work has also analyzed the effects of different materials as an Electron Transport Layer and Hole Transport Layer, and the effects of back metal contact, absorber layers defects, light radiation power, light direction, etc. Molecular Dynamic study has found that the thermal properties of MAPbI3 and MASnI3 perovskite layers are favorable to the solar cell efficiency and performance. In addition, the effect of temperature variation on solar cell performance is investigated, and the impact of defect density of the absorber layer is also explored. It was found that low defect density is helpful to achieve high device performance. Moreover, the work function of the front metal contact plays an important role, and it should be more than 5.31 eV for the proposed devices to achieve high performance.

The density, conductivity, and viscosity of the 1,3-dimethyl-2-imidazolinone and lithium nitrate (DMI– LiNO3) solvated ionic liquid were measured as a function of temperature. Additionally, the electrochemical mechanism and electrodeposition of neodymium from the DMI–LiNO3 solvated ionic liquid were investigated. Cyclic voltammetry results indicate that the electrochemical reduction of Nd(III) is irreversible and proceeds via one-step with three-electron transfer, which is controlled by diffusion with a diffusion coefficient of 5.08×10−8 cm2/s. Energy- dispersive X-ray spectrometry and X-ray photoelectron spectroscopy data confirm that the electrodeposit obtained after electrodeposition at −4 V (vs Ag) using the DMI–LiNO3–Nd(CF3SO3)3 solvated ionic liquid contains metallic neodymium.

A model was built to simulate liquid aluminum leakage during the casting process, including transient trough flow, orifice outflow, and spread, to prevent the explosion. A comparison between the simulation data and the theoretical calculation results verifies that the model has remarkable adaptability and high accuracy. Although the height of liquid aluminum in the mixing furnace and outlet radius are changed, the molten aluminum will not leak during the casting process. The aluminum in the trough moves forward in a wave-like motion and causes a leakage. The spread of the leaked aluminum resembles a long strip on the ground. The leakage amount and spread area of liquid aluminum increase with increasing the height of liquid aluminum in the mixing furnace.

To investigate the electrochemical reduction mechanism of Ta(V) in ethylene carbonate and aluminum chloride (EC−AlCl3) solvate ionic liquid, cyclic voltammetry experiments were conducted on a tungsten working electrode. Four reduction peaks were observed in the cyclic voltammogram of the EC−AlCl3−TaCl5 ionic liquid. The reduction peaks at −0.55, −0.72, and −1.12 V (vs Al) were related to the reduction of Ta(V) to tantalum metal by three stages including the formation of Ta(IV) and Ta(III) complex ions. The reduction of Ta(III) to tantalum metal was an irreversible diffusion-controlled reaction with a diffusion coefficient of 3.7×10−7 cm2/s at 323 K, and the diffusion activation energy was 77 kJ/mol. Moreover, the cathode products at 323 K were characterized by scanning electron microscopy, energy-dispersive spectroscopy, and X-ray photoelectron spectroscopy. The results showed that tantalum metal and tantalum oxides were obtained by potentiostatic electrodeposition at −0.8 V for 2 h.

In this paper, Tunnel Oxide Passivated Contact (TOPCon) silicon solar cells with the industrial area (244.32 cm2) are fabricated on N-type silicon substrates. Both the ultra-thin tunnel oxide layer and phosphorus doped polycrystalline silicon (polysilicon) thin film are prepared by the LPCVD system. The wrap-around of polysilicon is observed on the surface of borosilicate glass (BSG). The polysilicon wrap-around can form a leakage current path, thus degrades the shunt resistance of solar cells, and leads to the degradation of solar cell efficiency. Different methods are adopted to treat the polysilicon wrap-around and improve shunt resistance of solar cells. The experimental results indicate that a chemical etching method can effectively solve the problem of polysilicon wrap-around and improve the performance of solar cells. Finally, a conversion efficiency of 22.81% has been achieved by our bifacial TOPCon solar cells, with Voc of 702.6 mV, Jsc of 39.78 mA/cm2 and FF of 81.62%.

To develop Martian soil simulant, basalts of the Chahar volcanic group in Wulanchabu, Inner Mongolia, China were selected as the simulant initial materials, which were ground and sorted to a predetermined particle size ratio, and small amounts of magnetite and hematite were added. The main phases of NEU Mars-1 simulant were plagioclase, augite and olivine. The glass transition and crystallization temperatures of NEU Mars-1 were 547.8 and 795.7 °C, respectively. The complex dielectric constant, magnetic conductivity (0.99–1.045), and dielectric loss tangent angles (0.0025–0.030) of NEU Mars-1 were all stable in the frequency range of 2–18 GHz. Mossbauer spectroscopy results showed that the mass ratio of Fe2+ to Fe3+ in the simulant was 77.6:22.4. The NEU Mars-1 Martian soil simulant demonstrated particle size ratio, chemical composition, phase composition, thermal stability, and dielectric property similar to Martian soil, and can be used as the substitute material to extract oxygen and metals with in-situ resource utilization technologies.

The pretilachlor has been widely used worldwide and has contaminated the environment for many years. The environmental fate of pretilachlor and its residues removal from the contaminated environment have attracted great concern. Reportedly, pretilachlor could partly be transformed to HECDEPA by Rhodococcus sp. B2. However, the effects of pretilachlor on soil bacterial communities and its complete metabolic pathway remain unknown. Herein, we investigated the mechanism of driving synergistic degradation of pretilachlor by strain B2 in the soil. The results revealed that pretilachlor showed a negative effect on bacterial communities and caused significant variations in the community structure. Strain B2 showed the ability to remediate the pretilachlor-contaminated soils and network analysis revealed that it may drive the enrichment of potential pretilachlor-degrading bacteria from the soil. The soil pretilachlor degradation may be facilitated by the members of the keystone families Comamonadaceae, Caulobacteraceae, Rhodospirillaceae, Chitinophagaceae, and Sphingomonadaceae. Meanwhile, Sphingomonas sp. M6, a member of the Sphingomonadaceae family, has been isolated from the strain B2 inoculation sample soil. The co-culture, comprising strain M6 and B2, could synergistic degrade pretilachlor within 30 h, which is the highest degradation rate. Strain M6 could completely degrade the HECDEPA via CDEPA and DEA. In the soil, a comparable pretilachlor degradation pathway may exist. This study suggested that strain B2 had the potential to drive the remediation of pretilachlor-contaminated soils.

The family of novel transmembrane proteins (TMEM) 132 have been associated with multiple neurological disorders and cancers in humans, but have hardly been studied in vivo. Here we report the expression patterns of the five Tmem132 genes (a, b, c, d and e) in developing mouse nervous system with RNA in situ hybridization in wholemount embryos and tissue sections. Our results reveal differential and partially overlapping expression of multiple Tmem132 family members in both the central and peripheral nervous system, suggesting potential partial redundancy among them.

The Hedgehog (Hh) signaling pathway is crucial for the development of vertebrate and invertebrate animals alike. Hh ligand binds its receptor Patched (Ptc), allowing the activation of the obligate signal transducer Smoothened (Smo). The levels and localizations of both Ptc and Smo are regulated by ubiquitination, and Smo is under additional regulation by phosphorylation and SUMOylation. Downstream of Smo, the Ci/Gli family of transcription factors regulates the transcriptional responses to Hh. Phosphorylation, ubiquitination and SUMOylation are important for the stability and localization of Ci/Gli proteins and Hh signaling output. Finally, Suppressor of Fused directly regulates Ci/Gli proteins and itself is under proteolytic regulation that is critical for normal Hh signaling.

Background: Since January 2020, COVID-19 has spread globally to more than 210 countries, and the epidemic lasted for more than 11 months. Scientists have studied many effective prevention and control strategies. Based on real-time big data on COVID-19 pneumonia captured by the Baidu App, our study aimed to analyse the characteristics of the COVID-19 pandemic in 10 epicentre countries. It also aimed to discuss the impact of politics, economy, and humanities on COVID-19 as well as effective strategies of prevention and control the epidemic. Methods: Based on the real-time big data report of the new coronavirus pneumonia epidemic in Baidu APP, collected from January 27 to December 22, 2020. Incidence and death data in the world and China, India, Europe UK, Italy, France, Spain, Russia, America Brazil, the United States, Mexico were collected.1 Excel 2016 was used to build a database and performed linear fitting analysis, R3.6.3 and ggplot2 package was used for descriptive statistical analysis. Current status and trends of morbidity and mortality in the world and epicenter countries were analyze. Findings: To December 22, 2020, in the recent 5 days, the top two incidence cases were America with 1,079,385 cases, and the United Kingdom with 197,037 cases; the bottom two were China with 507 cases, and Mexico 48,416 cases. The top two mortality cases were America with 12,180 cases, and Brazil with 3,500 cases; the bottom two were China 7 Cases, and Spain 664 cases. The top two incidence rates were in America 0.3303%, and the United Kingdom 0.2959%;the bottom two were in China 0.0000%,and India 0.0097%.The top two mortality rates were in Italy 0.0044%, and the United Kingdom 0.0042%;the bottom two were in China 0.0000%,and India 0.0001%.From January 27 to December 22, 2020,The top two cumulative confirmed cases were in America with 18,494,265 cases, and India with 10,094,801 cases; the bottom two were China 95,998 cases, and Mexico 1,325,915 cases. The top two incidence rate were America 5.6597%,and Spain 3.9442%;the bottom two were China 0.0069%, and India 0.7624%.The top two mortality cases were America with 327,171 cases, and Brazil with 187,322 cases; the bottom two were China with 4,773 cases, and Spain with 49,260 cases. The top two mortality rates were Italy 0.1144%,and Spain 0.1062%;the bottom two were China 0.0003%,and India 0.0111%.Compared with the global cumulative incidence rate general trend (κ=0.0141), there are significant differences between America (κ=0.0716), Brazil (κ=0.0579), Spain (κ=0.0547), and China (κ=4E-05). Compared with the global incidence rate in recent trend (κ=0.0283), there are obvious differences between America (κ=0.2962), Italy (κ=0.2171), France (κ=0.1840), and China (κ=1E-05).Compared with the global cumulative mortality general trend (κ=0.0003), there are significant differences between Brazil (κ=0.0016),America and Mexico (κ=0.0015), Spain and the United Kingdom (κ=0.0014), Italy (κ=0.0013), and China (κ=3E-06).Compared with the global incidence rate in recent trend (κ=0.0006), there are significant differences between Italy (κ=0.0048), France (κ=0.0037), America (κ=0.0033), and China (κ=E-07). Interpretation: The lives of people in India, the United States and most of epicenter countries in European and American are suffering from grave damage. The mutation of Coronavirus has made the already serious epidemic worse. The current epidemic situation in the epicenter country and the mutation of Coronavirus also pose a serious threat to the lives of people in the non-epicenter country. It is urgent to construct a new anti-epidemic strategy based on aseptic technology to end the devastation caused by Coronavirus to human beings. Funding Statement: The Key Projects of Research and Development of Hainan Province (No.: ZDYF2020109) Declaration of Interests: We declare no competing interests.

3-Hydroxyanthranilate 3,4-dioxygenase (HAO) is an iron-dependent protein that activates O(2) and inserts both oxygen atoms into 3-hydroxyanthranilate (3-HAA). An intriguing question is how HAO can rapidly bind O(2), even though local O(2) concentrations and diffusion rates are relatively low. Here, a close inspection of the HAO structures revealed that substrate- and inhibitor-bound structures exhibit a closed conformation with three hydrophobic loop regions moving toward the catalytic iron center, whereas the ligand-free structure is open. We hypothesized that these loop movements enhance O(2) binding to the binary complex of HAO and 3-HAA. We found that the carboxyl end of 3-HAA triggers changes in two loop regions and that the third loop movement appears to be driven by an H-bond interaction between Asn(27) and Ile(142). Mutational analyses revealed that N27A, I142A, and I142P variants cannot form a closed conformation, and steady-state kinetic assays indicated that these variants have a substantially higher K(m) for O(2) than WT HAO. This observation suggested enhanced hydrophobicity at the iron center resulting from the concerted loop movements after the binding of the primary substrate, which is hydrophilic. Given that O(2) is nonpolar, the increased hydrophobicity at the iron center of the binary complex appears to be essential for rapid O(2) binding and activation, explaining the reason for the 3-HAA–induced loop movements. Because substrate binding-induced open-to-closed conformational changes are common, the results reported here may help further our understanding of how oxygen is enriched in nonheme iron-dependent dioxygenases.

The kynurenine pathway is the primary route for l-tryptophan degradation in mammals. Intermediates and side products of this pathway are involved in immune response and neurodegenerative diseases. This makes the study of enzymes, especially those from mammalian sources, of the kynurenine pathway worthwhile. Recent studies on a bacterial version of an enzyme of this pathway, 2-aminomuconate semialdehyde (2-AMS) dehydrogenase (AMSDH), have provided a detailed understanding of the catalytic mechanism and identified residues conserved for muconate semialdehyde recognition and activation. Findings from the bacterial enzyme have prompted the reconsideration of the function of a previously identified human aldehyde dehydrogenase, ALDH8A1 (or ALDH12), which was annotated as a retinal dehydrogenase based on its ability to preferentially oxidize 9-cis-retinal over trans-retinal. Here, we provide compelling bioinformatics and experimental evidence that human ALDH8A1 should be reassigned to the missing 2-AMS dehydrogenase of the kynurenine metabolic pathway. For the first time, the product of the semialdehyde oxidation by AMSDH is also revealed by NMR and high-resolution MS. We found that ALDH8A1 catalyzes the NAD(+)-dependent oxidation of 2-AMS with a catalytic efficiency equivalent to that of AMSDH from the bacterium Pseudomonas fluorescens. Substitution of active-site residues required for substrate recognition, binding, and isomerization in the bacterial enzyme resulted in human ALDH8A1 variants with 160-fold increased K(m) or no detectable activity. In conclusion, this molecular study establishes an additional enzymatic step in an important human pathway for tryptophan catabolism.

An aluminum-containing solvate ionic liquid, DMI–AlCl3 (1 M)–MgCl2 (0.5 M) was used as the electrolyte for magnesium electrodeposition. The results of Raman spectroscopy and 27Al nuclear magnetic resonance spectroscopy indicated the existence of aluminum-containing [AlCl4]- and [AlCl2(DMI)4]+ in the DMI–AlCl3 (1 M) system. When 0.5 M MgCl2 was added to DMI–AlCl3, the Mg(II) species was [MgCl(DMI)n]+. X-ray diffraction analysis indicated that a coating of Al3Mg2 can be prepared by potentiostatic electrodeposition at −1.45 V (vs. Al) at 323 K on a copper sheet cathode.

In this study, Al–Si alloy, a precursor of the solar-grade silicon, was prepared via the aluminothermic reduction–molten salt electrolysis of SiO2 in KF–AlF3 molten salt by employing liquid aluminum as the working cathode. The reaction mechanism of the aluminothermic reduction of SiO2 in KF–AlF3 molten salt at 750 °C was determined by thermogravimetry–differential scanning calorimetry. The reaction rate equation for the aluminothermic reduction of SiO2 in KF–AlF3 molten salt was: d α dt = 7.156 × 10 24 e − 4.688 × 10 5 RT ( 1 − α ) 1.734 . In 49.4 wt.% KF–47.6 wt.% AlF3–3 wt.% SiO2 molten salt at 750 °C, the Si content in the Al–Si alloy obtained by the aluminothermic reduction–molten salt electrolysis of SiO2 was 24.53 wt.%. Compared with solely aluminothermic reduction of SiO2, the current efficiency in the process of the aluminothermic reduction–molten salt electrolysis of SiO2 was evaluated. The results reveal that the Al–Si alloy is predominantly prepared in the aluminothermic reduction step, while supplemented by electrolysis. The calculated Faradic current efficiency of the proposed aluminothermic reduction–molten salt electrolysis process was 28.4%.

In this paper, a 500-W-level all-fiber amplifier operating near 980 nm is demonstrated firstly, to the best of our knowledge. The amplifier is fabricated with a 105/250-μm core/cladding-diameter double-cladding Yb-doped fiber (DCYF). By optimizing the length of DCYF, the record 556-W output power and 50.5% slope efficiency are obtained with a 1.85-W seed light, and about 30.9 dB peak-to-peak suppression of 1030-nm amplified spontaneous emission (ASE) is realized. Furthermore, the strong in-band ASE is also observed in experiment, which limits the power up-scaling of the fiber amplifier. By analyzing the origin of the in-band ASE, it is revealed that optimizing the seed light should be beneficial to the suppression of in-band ASE. Besides, the beam quality is measured at the maximum output power and the M2 factor is about 23.6. The experimental study should be able to provide significant guidance for understanding and designing the high-power three-level fiber lasers and amplifiers.

In this paper, a cost-effective 50-W-level all-fiber oscillator operating near 980 nm is demonstrated with the 20-μm core-diameter double-cladding Yb-doped fiber (DCYF) firstly, to the best of our knowledge. By using the 15-degree angle-cleaved output fiber end-facet, the record 54.8-W output power is obtained with the slope efficiency about 15.6%. It is revealed that increasing the cleaved angle (or suppressing the optical feedback) of output fiber end-facet should be an effective way to improve the performance of the fiber oscillator. Then, by optimizing the length of DCYF, the slope efficiency is slightly improved to 15.8% because of better suppression of the amplified spontaneous emission (ASE) around 1030 nm. It is also found that the effect of pumping scheme is negligible on the performance of the fiber oscillator. The beam quality is measured and the M2 factor is about 2.5. Better beam quality can be expected by lowering the numerical aperture (NA) of the active fiber core. The all-fiber oscillator can provide a well solution for the high-power core-pump source.

Few articles are reported for the simultaneous separation and sensitive detection of the kynurenine pathway (KP) metabolites. This work describes a capillary electrochromatography-mass spectrometry (CEC-MS) method using acrylamido-2-methyl-1-propanesulfonic acid (AMPS) functionalized stationary phase. The AMPS column was prepared by first performing silanization of bare silica with gamma-maps, followed by polymerization with AMPS. The CEC-MS/MS methods were established for six upstream and three downstream KP metabolites. The simultaneous separation of all nine KP metabolites is achieved without derivatization for the first time in the open literature. Numerous parameters such as pH and the concentration of background electrolyte, the concentration of the polymerizable AMPS monomer, column length, field strength, and internal pressure were all tested to optimize the separation of multiple KP metabolites. A baseline separation of six upstream metabolites, namely tryptophan (TRP), kynurenine (KYN), 3-hydroxykynurenine (HKYN), kynurenic acid (KA), anthranilic acid (AA), and xanthurenic acid (XA), was possible at pH 9.25 within 26 min. Separation of six downstream and related metabolites, namely: tryptamine (TRPM), hydroxy‑tryptophan (HTRP), hydroxyindole-3 acetic acid (HIAA), 3-hydroxyanthranilic acid (3-HAA), picolinic acid (PA), and quinolinic acid (QA), was achieved at pH 9.75 in 30 min. However, the challenging simultaneous separation of all nine KP metabolites was only accomplished by increasing the column length and simultaneous application of internal pressure and voltage in 114 min. Quantitation of KP metabolites in commercial human plasma was carried out, and endogenous concentration of five KP metabolites was validated. The experimental limit of quantitation ranges from 100 to 10,000 nM (S/N = 8–832, respectively), whereas the experimental limit of detection ranges from 31 to 1000 nM (S/N = 2–16, respectively). Levels of five major KP metabolites, namely TRP, KYN, KA, AA, and QA, and their ratios in patient plasma samples previously screened for inflammatory biomarkers [C-reactive protein (CRP) and tumor necrosis factor-alpha (TNF-α)] was measured. Pairs of the level of metabolites with significant positive correlation were statistically evaluated.

In this work Cu2O microcrystals with various morphologies including octahedrons, cubes and hollow spheres were employed as the antimicrobial for the devitalization of Escherichia coli (E. coli). It was found that during the devitalization of E. coli, Cu2O microcrystals with various shapes presented similar change trend and finally was converted into flowerlike microstructures constructed by abundant nanosheets. Also, the shape change always started from {1 0 0} planes.

In this work, urea and 1-butyl-3-methylimidazolium chloride (urea-BMIC) deep eutectic solutions were used as electrolytes for electrodeposition of lead from lead oxide. The electrochemical behavior of Pb (II) ions was investigated by cyclic voltammetry, chronopotentiometry, and chronoamperometry techniques at 353–373 K. Cyclic voltammograms and chronopotentiograms indicate that the reduction of Pb (II) ions to Pb is a diffusion-controlled quasi-reversible process and it proceeds via one step two-electron transfer process at −0.38 V (vs. Ag). The diffusion coefficient of Pb (II) ions increases from 3.22 × 10 −8 cm 2 s −1 to 1.49 × 10 −7 cm 2 s −1 as temperature increases from 353 K to 373 K. The activation energy for diffusion is determined to be 83.93 kJ mol −1 . In addition, results from chronoamperometry show that lead deposition involves in a three-dimensional instantaneous nucleation and diffusion-controlled growth. On the other hand, the electrodeposit on a Cu substrate was pure Pb as confirmed by X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS). Scanning electron microscopy (SEM) image indicated that a uniform, dense, and non-dendritic coating with grain size of 3 μm in diameter was prepared by potentiostatic electrolysis at −0.4 V (vs. Ag). The optimized current efficiency (96.17%) and energy consumption (0.11 kWh kg −1 ) was obtained by potentiostatic electrolysis at −0.4 V (vs. Ag) and 373 K from urea-BMIC deep eutectic solutions containing 0.072 mol dm −3 PbO.

Guiyu, China, is well-known for the crude disposal of electronic waste (EW) and severe persistent organic pollutants (POPs). Therefore, in this study, the occurrence, composition, and source of polybrominated diphenyl ethers (PBDEs), 2,2',4,4',5,5'-hexabromobiphenyl (BB153), some novel brominated flame retardants (NBFRs), Dechlorane Plus (DP) and polybrominated dibenzo-p-dioxins/dibenzofurans (PBDD/Fs) in farmland soils covering Guiyu were studied. In EW disposal area soils, PBDEs were the most abundant FRs, with concentrations of 13-1014 ng g-1. The primary PBDE sources were technical Penta- and Deca-BDE mixtures in northern and southern Guiyu, respectively. The levels of BB153 were relatively low, possibly because it has been banned in the 1970s. The concentrations of hexabromobenzene (HBB) were 0.048-3.3 ng g-1, while pentabromoethylbenzene (PBEB) was almost not detected in the soils. Two alternatives to commercial PBDEs, decabromodiphenyl ethane (DBDPE) and 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE), were the primary NBFRs, with concentrations of 1.8-153 ng g-1 and 0.43-15 ng g-1, respectively. DP was another primary FR, with concentrations of 0.57-146 ng g-1. Moreover, syn-DP and anti-DP isomers were not stereoselectively decomposed during the EW disposal process and were therefore present in their original fractions in the soils. The levels of PBDD/Fs in EW disposal area soils were 2.5-17 pg TEQ g-1. 1,2,3,4,6,7,8-HpBDF and OBDF were the dominant congeners, mainly derived from processing, pyrolysis and combustion of BFRs. The regional distribution of pollutants was shown to be related to the disposal manner of EW, with their open thermal disposal tending to release more highly brominated compounds such as BDE209, DBDPE, and 1,2,3,4,6,7,8-HpBDF. Additionally, some riverbank sites were heavily polluted because of nearby point sources, downwind Simapu (SMP) town without EW disposal activity was also contaminated by these pollutants.

In-situ utilization of lunar resources for the production of metals and oxygen is essential for lunar exploration. The main emphasis of this article is on a candidate approach that combined aluminothermic reduction and electrolysis process in cryolite molten salts to produce both Al-based alloy and oxygen from lunar soil simulants. The influences of reductant amount and reaction time on the aluminothermic reduction of coal fly ash in cryolite melts at 1233 K (960 °C) were studied. The results obtained by XRF, XRD, SEM and EDS analysis show that the products mainly contain Al, Si, Fe, and little Ti, while the main phases of the products are Al and Si. With the increase of reaction time, the content of Si in alloy products increases from 4.43 wt% to 7.47 wt%. In addition, the remaining alumina-rich cryolite melts was electrolyzed at 1233 K (960 °C) using 56 wt%Fe-44 wt%Ni alloy inert anode. The cathode product obtained by galvanostatic electrolysis for 4 h was characterized, and the results showed that the phase composition of the cathode product was pure Al, while the highest aluminum content in the cathode product is 99.431 wt%. Besides, the outlet gas at the anode during electrolysis is pure oxygen according to the analysis of gas chromatography.

CYP121, the cytochrome P450 enzyme in Mycobacterium tuberculosis that catalyzes a single intramolecular C–C cross-linking reaction in the biosynthesis of mycocyclosin, is crucial for the viability of this pathogen. This C–C coupling reaction represents an expansion of the activities carried out by P450 enzymes distinct from oxygen insertion. Although the traditional mechanism for P450 enzymes has been well studied, it is unclear whether CYP121 follows the general P450 mechanism or uses a different catalytic strategy for generating an iron-bound oxidant. To gain mechanistic insight into the CYP121-catalyzed reaction, we tested the peroxide shunt pathway by using rapid kinetic techniques to monitor the enzyme activity with its substrate dicyclotyrosine (cYY) and observed the formation of the cross-linked product mycocyclosin by LC-MS. In stopped-flow experiments, we observed that cYY binding to CYP121 proceeds in a two-step process, and EPR spectroscopy indicates that the binding induces active site reorganization and uniformity. Using rapid freeze-quenching EPR, we observed the formation of a high-spin intermediate upon the addition of peracetic acid to the enzyme–substrate complex. This intermediate exhibits a high-spin (S = 5/2) signal with g values of 2.00, 5.77, and 6.87. Likewise, iodosylbenzene could also produce mycocyclosin, implicating compound I as the initial oxidizing species. Moreover, we also demonstrated that CYP121 performs a standard peroxidase type of reaction by observing substrate-based radicals. On the basis of these results, we propose plausible free radical–based mechanisms for the C–C bond coupling reaction.

Aldehyde dehydrogenase typically performs oxidation of aldehydes to their corresponding carboxylic acid while reducing NAD(P)+ to NAD(P)H via covalent catalysis mediated by an active-site cysteine residue. One member of this superfamily, the enzyme 2-aminomuconate-6-semialdehyde dehydrogenase (AMSDH), is a component of the kynurenine pathway, which catabolizes tryptophan in mammals and certain bacteria. AMSDH catalyzes the NAD+-dependent oxidation of 2-aminomuconate semialdehyde to 2-aminomuconate. We recently determined the first crystal structure of AMSDH and several catalytic cycle intermediates. A conserved asparagine in the oxyanion hole, Asn-169, is found to be H-bonded to substrate-derived intermediates in the active site of AMSDH during catalysis, including both the covalently bound thiohemiacetal and thioacyl intermediates. To better interrogate the significance of the hydrogen bond provided by Asn-169 to the reaction mechanism of AMSDH, we created Ala, Ser, Asp, and Gln mutants and studied them using biochemical, kinetic, crystallographic, and computational studies. The in crystallo chemical reaction of the primary substrate with the co-crystalized complex of the N169D mutant and NAD+ led to the successful trapping of a new catalytic intermediate that was not previously seen. The structural and computational data are consistent with a substrate imine/enol tautomer intermediate being formed prior to the formation of the covalent bond between the substrate and the active-site cysteine. Thus, AMSDH surprisingly includes an isomerization process within its known catalytic mechanism. These data establish a hidden intrinsic isomerization activity of the dehydrogenase and allow us to propose a pitcher-catcher type of catalytic mechanism for the isomerization.

The ionic structure of the KF-AlF3-Al2O3 system was studied using in situ high-temperature Raman spectroscopy and quantum mechanics calculations. The complexes in the KF-AlF3-Al2O3 system with different molar ratios of KF to AlF3 were AlF63−, AlF52−, AlF4−, Al2OF4, Al2OF84−, Al2OF62−, and Al2O2F42−. The structures of Al2OF4, Al2OF84−, Al2OF62−, and Al2O2F42− were optimized considering that the counterion K+, Al2OF4 exhibits D2d point group symmetry, K4Al2OF8 and K2Al2OF6 exhibit C2v point group symmetry, and K2Al2O2F4 exhibits C2h point group symmetry. The experimental main Raman bands of Al2OF84−, Al2OF62−, and Al2O2F42− were at 495 cm−1, 465 cm−1, and 410 cm−1, respectively, after comparing their theoretical Raman spectra. The forms and contents of the oxygen-containing complex ions in the system were related to the molar ratio of KF to AlF3 and to the concentration of alumina. AlF63−, AlF52−, AlF4−, and Al2OF4 were found in the molten KF-AlF3-Al2O3 system with a KF-to-AlF3 molar ratio of 1.22 at a temperature of 1003 K. In the KF-AlF3-Al2O3 system with a KF-to-AlF3 molar ratio of 2 at a temperature of 1273 K, when the alumina concentration was less than or equal to 10 wt%, it contained AlF63−, AlF52−, AlF4−, Al2OF4, and Al2OF84−, and when the alumina concentration reached 12 wt%, Al2OF62− and Al2O2F42− appeared. In the KF-AlF3-Al2O3 system with a KF-to-AlF3 molar ratio of 3 at a temperature of 1273 K, when the alumina concentration was less than or equal to 10 wt%, the system contained AlF63−, AlF52−, AlF4−, Al2OF4, and Al2OF84−. When the alumina concentration increased to 14 wt%, Al2OF62− and Al2O2F42− began to appear but AlF4− disappeared. As the concentration of alumina increased, the contents of Al2OF62− and Al2O2F42− increased. The ionic reactions that formed the various oxygen-containing complexes were obtained. The occurrence of these chemical reactions was related to the molar ratio of KF to AlF3 in the system and the alumina concentration. When the KF-AlF3-Al2O3 molten system with KF-to-AlF3 molar ratios of 1.22, 2 and 3 were used as the aluminum electrolytes, the ion discharged at the anode was Al2OF84−(except for the system with a KF-to-AlF3 molar ratio of 1.22 in which the Al2OF4 was discharged at the anode), and the ion discharged at the cathode was Al2OF4 according to wave function analyses.

In this paper, a more-than ten-Watt all-fiber oscillator operating near 980nm is demonstrated with a commercially-available 20/125-μm double-cladding Yb-doped fiber (DCYF) firstly, to the best of our knowledge. The 15-W output power is eventually obtained with the slope efficiency of 13 % and central wavelength around 978 nm. Moreover, the power scalability of the 980-nm fiber oscillator is also investigated numerically. It is revealed that more-than 20 % slope efficiency can be obtained with this kind of DCYF. It is also found that besides pump power, the cladding light stripper (CLS) is another limitation in the 980-nm fiber oscillator, and more-than 50-W output power can be obtained if more-than 80-W residual pump light can be filter out with each CLS.

Tunnel oxide passivated contact (TOPCon) industrial (244.32 cm2) c-Si solar cell is fabricated in this paper. Both the ultra-thin silicon oxide layer and intrinsic polycrystalline silicon layer are deposited by low-pressure chemical vapor deposited (LPCVD). Then intrinsic polycrystalline silicon layers are doped by thermal diffusion of POCl3 in an industrial-scale quartz tube furnace. Experiment conditions like polycrystalline silicon thickness, diffusion temperature, diffusion time and POCL3 flow rate on the passivation quality of TOPCon structure are investigated in detail and low recombination current density ~8 fA/m2 has been achieved for c-Si/SiOx/poly-Si(70 nm)/SiNx structure at diffusion temperature 850 °C. A variation about 30–40 mV has been observed between the iVoc and Voc for 70 nm samples, which should be attributed to the metallization-induced degration. Not consistent with the result obtained from symmetric samples, both an improvement to the solar cell efficiency has been found for 70 nm thick poly-Si and 170 nm thick poly-Si at the diffusion temperature above the optimal diffusion temperature. Finally, by optimizing the polysilion thickness and phosphorus diffusion, the champion solar cell efficiency of 22.81% is achieved, with Voc of 702.6 mV, Jsc of 39.78 mA/cm2, FF of 81.62%.

The development of interdigitated back contact silicon heterojunction has been flourishing in the field of solar cells. The front surface field has a decisive influence on the electrical field effect passivation of interdigitated back contact silicon heterojunction solar cells, and the effect of passivation layers on the performance of solar cells needs to be clarified. In this study, the two-dimension TCAD models of the doped n+-a-Si: H layer and SiNx with a fixed charge layer were established by the Sentaurus code, respectively. The space charge density and electric field intensity, carrier transportation, and distribution of current density were numerically analyzed to evaluate the effect of these two front surfaces on the performance of interdigitated back contact silicon heterojunction solar cells. The results show that for SiNx, the root cause of the field passivation is the surface fixed charge density. The combination of the doping concentration and layer thickness directly affects the field passivation of n+-a-Si: H. Based on the intuitive carrier transport vector, the selective transportation of the carrier near the surface is proved by the front surface field, which effectively inhibits the recombination. The current density distribution on the cross-section reveals that a strong front surface field is an effective way to reduce the internal recombination in particular. Considering practical operating conditions, a doping concentration of 1e20 cm−3, in combination with 7 nm layer thickness, potentially improves the front surface field of n+ a-Si: H leading to the maximum conversion efficiency of 27.41%, with the voltage increased by 32.8 mV and the fill factor reaching 86.84%.

Traditional black silicon solar cells show relatively low efficiencies due to the high surface recombination occurring at the front surfaces. In this paper, we present a surface modification process to suppress surface recombination and fabricate highly efficient industrial black silicon solar cells. The Ag-nanoparticle-assisted etching is applied to realize front surface nanostructures on silicon wafers in order to reduce the surface reflectance. Through a further tetramethylammonium hydroxide (TMAH) treatment, the carrier recombination at and near the surface is greatly suppressed, due to a lower surface dopant concentration after the surface modification. This modified surface presents a low reflectivity in a range of 350–1100 nm. Large-area solar cells with an average conversion efficiency of 19.03% are achieved by using the TMAH treatment of 30 s. This efficiency is 0.18% higher than that of standard silicon solar cells with pyramidal surfaces, and also a remarkable improvement compared with black silicon solar cells without TMAH modifications.

The ultraviolet (UV) curable organic/inorganic hybrid coating is a kind of environment friendly paint products with rapid development in recent decade. It combines UV curing and nanofabrication technique. Due to its distinct advantages of zero volatile organic compounds emission, high curing rate at room temperature, and excellent performance, UV curable organic/inorganic hybrid coating has been considered as a green product with extensive application prospect. In this review, we focus on the preparation methods of UV curable organic/inorganic hybrid coatings including blending method, sol gel process, intercalation and in-situ reaction. All the preparation methods have the same core concept of incorporation between the organic and inorganic composition in molecular level in order to take full advantages of both organic and inorganic composition. The properties of hybrid coatings can be enhanced by the inorganic incorporation into the organic matrix, such as abrasive resistance, heat resistance, corrosion resistance, chemical stability and etc. The research progress on different inorganic particles applied in UV curable organic/inorganic hybrid coatings is also summarized.

Summary During development, intestinal epithelia undergo dramatic morphogenesis mediated by mesenchymal signaling to form villi, which are required for efficient nutrient absorption and host defense. Although both smooth-muscle-induced physical forces and mesenchymal cell clustering beneath emerging villi are implicated in epithelial folding, the underlying cellular mechanisms are unclear. Hedgehog (Hh) signaling can mediate both processes. We therefore analyzed its direct targetome and revealed GLI2 transcriptional activation of atypical cadherin and planar cell polarity (PCP) genes. By examining Fat4 and Dchs1 knockout mice, we demonstrate their critical roles in villus formation. Analyses of PCP-mutant mice and genetic interaction studies show that the Fat4-Dchs1 axis acts in parallel to the core-Vangl2 PCP axis to control mesenchymal cell clustering. Moreover, live light-sheet fluorescence microscopy and cultured PDGFRα+ cells reveal a requirement for PCP in their oriented cell migration guided by WNT5A. Therefore, mesenchymal PCP induced by Hh signaling drives cell clustering and subsequent epithelial remodeling.

Trade volume of agricultural products can be used to quantify the virtual land transfers between countries. This study assessed the virtual land trade (VLT) associated with the global trade of agricultural products using specific crop yield of exporting countries and gave insights in characteristics of different products and different countries. In addition, the features of trade connections were also displayed by network analysis. The results showed that the total virtual land within global agricultural trade increased from 128 million hectare (ha) in 1986 to 350 million ha in 2016, the average annual growth rate was 5.73 %. Increases in trade of oil crops contributed the largest share to this. The proportion of exported land area in total harvested land area increased for almost all categories of agricultural products. Countries engaged in global agricultural trade could be divided into three groups, net exporters, net importers and countries with balanced VLT. The net importers could be further divided into the countries with absolutely scarce land resources and the countries with relative scarce resources. All net virtual land exporters are the countries with more land resources per capita, such as the United States, Brazil and Argentina. Income growth and changes in diet structure are main factors driving increases in VLT. The VLT network became more complex over the study period, with the number of import and export nodes increasing continuously, and the cumulative distributions of export and import node strength following power law distributions. The major links and players within national, geographic, and economic groups also changed significantly over the study period. VLT has a deep impact on society, economy and environment, appropriate policies should be taken to make these interlinkages more sustainable for both importers and exporters.

The high-power 980-nm superfluorescent Yb-doped fiber source (SYFS) fabricated with the distributed side-coupled cladding-pumped (DSCCP) fiber is studied with the purpose of improving its efficiency. In experiment, by strengthening the pump light coupling of DSCCP fiber, more-than 23% slope efficiency with the record value of 23-W 980-nm emission is obtained. By means of the numerical study, it is revealed that the 980-nm SYFS efficiency can also be enlarged by optimizing the dopant concentration even with the relatively weak pump coupling, which provides an alternative way to improve the efficiency of SYFS. The pertinent results can be of great importance for studying and designing the 980-nm Yb-doped fiber source.

This paper reports on an industrially applicable approach to create efficient Al-doped p + regions alloyed from screen-printed pastes for the application as rear emitters in n -type silicon solar cells. The influences of polished and pyramidal rear surfaces on the formation of Si–Al alloy and saturation current are discussed. We demonstrate that a thin SiO 2 layer on Si–Al interface can mitigate the inhomogeneous Al diffusion during alloying process and develop the transport properties. Furthermore, we apply this SiO 2 layer in our n + np + solar cells, which exhibit lower series resistance and fine IQE response as a result of the improved Al emitter quality. For large-area n -type silicon solar cells (239 cm 2 ) with a full-area Al- p + rear emitter, we achieved an 18.8% efficient cell with an open-circuit voltage of 637.4 mV. Remarkable gains of 1.6% on average efficiency, 0.8 mA/cm 2 on J sc , 8.6 mV on open-circuit voltage and 4.1% on FF are obtained, comparing with the solar cells fabricated by standard industrial process.

The rubredoxin motif is present in over 74,000 protein sequences and 2,000 structures, but few have known functions. A secondary, non-catalytic, rubredoxin-like iron site is conserved in 3-hydroxyanthranilate 3,4-dioxygenase (HAO), from single cellular sources but not multicellular sources. Through the population of the two metal binding sites with various metals in bacterial HAO, the structural and functional relationship of the rubredoxin-like site was investigated using kinetic, spectroscopic, crystallographic, and computational approaches. It is shown that the first metal presented preferentially binds to the catalytic site rather than the rubredoxin-like site, which selectively binds iron when the catalytic site is occupied. Furthermore, an iron ion bound to the rubredoxin-like site is readily delivered to an empty catalytic site of metal-free HAO via an intermolecular transfer mechanism. Through the use of metal analysis and catalytic activity measurements, we show that a downstream metabolic intermediate can selectively remove the catalytic iron. As the prokaryotic HAO is often crucial for cell survival, there is a need for ensuring its activity. These results suggest that the rubredoxin-like site is a possible auxiliary iron source to the catalytic center when it is lost during catalysis in a pathway with metabolic intermediates of metal-chelating properties. A spare tire concept is proposed based on this biochemical study, and this concept opens up a potentially new functional paradigm for iron-sulfur centers in iron-dependent enzymes as transient iron binding and shuttling sites to ensure full metal loading of the catalytic site.

17.3% efficient black silicon (b-Si) solar cell without antireflection coating was achieved via tetramethylammonium hydroxide (TMAH) etching after the formation of the diffusion emitter. Large area (156 × 156 mm2) b-Si wafers were prepared by silver-nanoparticle-assisted etching on pyramid-structured silicon wafers. The modification of nanostructures of silicon surface by TMAH etching suppresses the surface recombination and Auger recombination at and near the emitter surface, and the effective minority carrier lifetime of the b-Si solar cells was improved from 10.7 μs to 20.8 μs. Although the average reflectance of the b-Si solar cell slightly increases from 2.38% to 2.71% via the process of TMAH etching, it is a small loss compared with the beneficial impact of the improvement of the carrier recombination lifetime. As a result, the internal quantum efficiency at short wavelength region was improved through the TMAH etch treatment, which was a main limiting factor for the efficiency of b-Si solar cells.

In developing countries such as China, there is a strong need for simple and rapid bioassays for the determination of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in environmental samples; i.e., flue gas and fly ash from waste incinerators. In this study, we applied the DR-EcoScreen cell (DR-cell) assay to determination of PCDD/Fs in 78 flue gas samples obtained from various waste incinerators in China between 2009 and 2011. The flue gas samples were obtained from four kinds of incinerators, classified into hazardous, medical and municipal-solid waste, and iron ore sintering, and the flue gas extracts were cleaned up using an SPD-600 automated-sample preparation device for DR-cell assay. The PCDD/Fs values obtained from the DR-cell assay were compared with those obtained from conventional high resolution gas chromatography-high resolution mass spectrometry (HRGC-HRMS) analysis. The bioanalytical equivalent (BEQ) values obtained from the DR-cell assay were very closely correlated with the international toxicity equivalent (I-TEQ) values from HRGC-HRMS analysis (r2=0.98, n=78), while the BEQ values were 5.52-fold higher than the I-TEQ values, as the PCDFs, which account for 80% of the total I-TEQ value, were overestimated by DR cell-assay. Therefore, we multiplied the BEQ values from the DR-cell assay by a conversion coefficient (0.181, the reciprocal of 5.52), and could approximate the TEQ values from the HRGC-HRMS analysis. These results suggest that the DR-cell assay combined with SPD-600 cleanup provides a promising method for the simple and rapid screening of PCDD/Fs levels in flue gas samples, such as those from various waste incinerators in China.

l -Tryptophan is an essential amino acid for mammals. It is utilized not only for protein synthesis but also for the biosynthesis of serotonin and melatonin by the serotonin pathway as well as nicotinamide adenine dinucleotide by the kynurenine pathway. Although the kynurenine pathway is responsible for the catabolism of over 90% of l -tryptophan in the mammalian intracellular and extracellular pools, the scientific field was dominated in the last century by studies of the serotonin pathway, due to the physiological significance of the latter’s catabolic intermediates and products. However, in the past decade, the focus gradually reversed as the link between the kynurenine pathway and various neurodegenerative disorders and immune diseases is increasingly highlighted. Notably, the first step of this pathway, which is catalyzed by heme-dependent dioxygenases, has been proven to be a potential target for immune regulation and cancer treatment. A thorough understanding of the intriguing chemistry of the heme-dependent dioxygenases may yield insight for the drug discovery of these prevalent illnesses. In this review, we survey enzymatic and mechanistic studies, initially started by Kotake and Masayama over 70 years ago, at the molecular level on the heme-dependent tryptophan dioxygenation reactions.

We present a simple method to fabricate parallel aligned CdSe/CdS nanorods (NRs) by the thermal annealing technique. Different packing structures were obtained by varying the amount of organic capping molecules in the washing process. The results showed that self-assembly of NRs can be aligned parallel to the substrate along with melted organic molecules during the annealing process; a larger space among NRs induced by more melted organics prevents the formation of the multilayer structures and thereby leads to the preferential monolayer. Heating induced organic molecules melted and thereby acts as the medium for self-assembly, and the amount of organics strongly influenced the nature of the self-assembly patterns. The results may offer a way toward controllable self-assembled nanocrystal superlattices for use in functional devices.

Although the crystal structure of α-amino-β-carboxymuconate-ϵ-semialdehyde decarboxylase from Pseudomonas fluorescens was solved as a dimer, this enzyme is a mixture of monomer, dimer, and higher order structures in solution. In this work, we found that the dimeric state, not the monomeric state, is the functionally active form. Two conserved arginine residues are present in the active site: Arg-51 and an intruding Arg-239* from the neighboring subunit. In this study, they were each mutated to alanine and lysine, and all four mutants were catalytically inactive. The mutants were also incapable of accommodating pyridine-2,6-dicarboxylic acid, a competitive inhibitor of the native enzyme, suggesting that the two Arg residues are involved in substrate binding. It was also observed that the decarboxylase activity was partially recovered in a heterodimer hybridization experiment when inactive R51(A/K) and R239(A/K) mutants were mixed together. Of the 20 crystal structures obtained from mixing inactive R51A and R239A homodimers that diffracted to a resolution lower than 3.00 Å, two structures are clearly R51A/R239A heterodimers and belong to the C2 space group. They were refined to 1.80 and 2.00 Å resolutions, respectively. Four of the remaining crystals are apparently single mutants and belong to the P42212 space group. In the heterodimer structures, one active site is shown to contain dual mutation of Ala-51 and Ala-239*, whereas the other contains the native Arg-51 and Arg-239* residues, identical to the wild-type structure. Thus, these observations provide the foundation for a molecular mechanism by which the oligomerization state of α-amino-β-carboxymuconate-ϵ-semialdehyde decarboxylase could regulate the enzyme activity.

The primary cilium is required for Hedgehog signaling. So far, all known ciliogenic proteins regulate Hedgehog signaling through their role in ciliogenesis. Here we show that the mouse DZIP1 regulates Hedgehog signaling through two mechanisms. First, DZIP1 interacts with GLI3, a transcriptional regulator for Hedgehog signaling, and prevents GLI3 from entering the nucleus. Second, DZIP1 is required for ciliogenesis. We show that DZIP1 colocalizes and interacts with CEP164, a protein localizing at appendages of the mother centrioles, and IFT88, a component of the intraflagellar transport (IFT) machinery. Functionally, both CEP164 and Ninein appendage proteins fail to localize to ciliary appendages in Dzip1 mutant cells; IFT components are not recruited to the basal body of cilia. Importantly, the accumulation of GLI3 in the nucleus is independent of loss of primary cilia in Dzip1 mutant cells. Therefore, DZIP1 is the first known ciliogenic protein that regulates Hedgehog signaling through a dual mechanism and that biochemically links IFT machinery with Hedgehog pathway components. Background: All known cilia-related proteins regulate Hedgehog signaling through their role in ciliogenesis. Results: The centrosomal protein DZIP1 interacts with and sequesters GLI3 transcription factor in the cytoplasm and also regulates ciliogenesis. Conclusion: DZIP1 is the first known cilia-related protein that regulates Hedgehog signaling through a dual mechanism. Significance: Understanding how DZIP1 regulates Hedgehog signaling provides new insights into the molecular mechanism of Hedgehog signal transduction.