Strong Spin Polarization Effect of Atomically Dispersed Metal Site Boosts the Selective Photocatalytic Nitrobenzene Hydrogenation to Aniline over Graphitic Carbon Nitride.

Atomically dispersed catalysts (ADCs) with a well-defined structure are theoretically desirable for a high-selectivity photocatalytic reaction. However, achieving high product selectivity remains a practical challenge for ADCs-based photocatalysts. Herein, we reveal a spin polarization effect on achieving high product selectivity (95.0%) toward the photocatalytic nitrobenzene (PhNO2) hydrogenation to aniline (PhNH2) on atomically dispersed Fe site-loaded graphitic carbon nitride (Fe/g-C3N4). In combination with the Gibbs free energy diagram and electronic structure analysis, the origin of the photocatalytic performance is attributed not only to the strong metal-support interaction between the Fe site and g-C3N4, but more importantly to the strong spin polarization effect that promotes the potential-determining step (PDS) of *PhNO to *PhNOH. This work could be helpful for the design of ADCs-based photocatalysts in view of the spin polarization effect.

2D CeO2 and a Partially Phosphated 2D Ni-Based Metal-Organic Framework Formed an S-Scheme Heterojunction for Efficient Photocatalytic Hydrogen Evolution.

Here, an S-scheme heterojunction was constructed on the basis of the modification of a Ni-based metal-organic framework (Ni-MOF) by different in situ treatment strategies. First, NiS2, NiO, and Ni2P were derived in situ on the surface of Ni-MOF through surface sulfonation, oxidation, and phosphatizing treatments. They can efficiently accept the electrons from the conduction band of Ni-MOF as the trap centers, thus improving the hydrogen production activity. Additionally, phosphatizing makes the electronegativity of Ni-MOF/P stronger than that of the original Ni-MOF, which can enhance the absorption of protons, thus promoting the hydrogen evolution reaction. Next, the S-scheme heterojunction was successfully built by the coupling of 2D CeO2 with Ni-MOF/P. The maximum hydrogen production rate of the hybrid catalyst (6.337 mmol g-1 h-1) is 14.18 times that of the untreated Ni-MOF due to the full utilization of photo-induced electrons. Finally, the probable hydrogen evolution mechanism was proposed by analyzing a series of characterization results and by the density functional theory (DFT) calculation.

Graphdiyne (CnH2n-2)-Based GDY/CuI/MIL-53(Al) S-Scheme Heterojunction for Efficient Hydrogen Evolution.

Graphdiyne (g-CnH2n-2) is a new carbon material composed of sp and sp2 hybrid carbon atoms. Since the synthesis by Li's team, graphdiyne has been widely studied in other fields because of its excellent properties. In this paper, graphdiyne was synthesized from copper-containing materials and the composite GDY/CuI/MIL-53(Al) S-scheme heterojunction is prepared for photocatalytic cracking of water to produce hydrogen. First, GDY/CuI was prepared by organic synthesis, and then GDY/CuI was anchored on the surface of MIL-53(Al) by in situ ultrasonic stirring. After the continuous optimization of experimental conditions, the final hydrogen evolution rate is much higher than that of MIL-53(Al). This efficient photocatalytic performance can be attributed to the S-scheme heterojunction formed by the unique energy band arrangement. At the same time, the mechanism of charge transfer was demonstrated by in situ irradiation X-ray photoelectron spectroscopy. The strong interaction among the three strongly promotes the separation and transfer of photogenerated electron-hole pairs.

Bridging Effect of S-C Bond for Boosting Electron Transfer over Cubic Hollow CoS/g-C3N4 Heterojunction toward Photocatalytic Hydrogen Production.

The construction of interfacial effects and chemical bonds between catalysts is one of the effective strategies to facilitate photogenerated electron transfer. A novel hollow cubic CoS is derived from Co-ZIF-9 and the S-C bond is successfully constructed between CoS and g-C3N4. The S-C bond acts as a bridge for electronic transmission, allowing the rapid transmission of photoelectron to hydrogen evolution active site in CoS. In addition, the results of electrochemical impedance spectroscopy and time-resolved photoluminescence spectroscopy show that the S-C bond acts as a bridge to quickly transfer photogenerated carriers in the composite material, and achieves the effect of high-efficiency hydrogen evolution. The hydrogen production of SgZ-45 reaches 9545 µmol·g-1 in 5 h, which is 53 and 12 times that of g-C3N4 and ZIF-9, respectively. The intrinsic mechanism of photoelectron transfer through S-C bonds can be further confirmed by density functional theory (DFT) calculations. This work provides new insights for building a chemical bond electron transfer bridge between MOF derivatives and nonmetallic photocatalytic materials.

Surface-Induced Engineering: P-Induced Formation of Surface Bonding States Based on the ZIF Synthesis Strategy for Photocatalytic Hydrogen Evolution.

The development of clean energy is one of the effective strategies to solve carbon peak and carbon neutrality. The severe recombination of photogenerated carriers is one of the fundamental reasons that hinder the development of photocatalysis. In this work, NiCo-MOF/ZIF was obtained by the "ZIF on MOF" strategy for the first time, and a stable bonding state of surface P(δ-)-Co/Ni(δ+)-O(δ-) was formed on the surface of the catalyst by a one-step oxidation-phosphorus doping strategy. The X-ray photoelectron spectroscopy technique proves that phosphorus doping forms a unique bonding state on the surface of CoO-NiO. The novel surface bonding state can effectively inhibit the recombination of photogenerated carriers and can increase the migration rate of photogenerated electrons, which accelerates the process of photocatalytic hydrogen evolution. Photocatalytic hydrogen evolution kinetics verifies that the formation of P(δ-)-Co/Ni(δ+)-O(δ-) bonding states can accelerate the process of photocatalytic hydrogen evolution, and the durability of the catalyst is verified by cycling experiments. This work provides a new strategy for catalyst synthesis, new horizons, and effective strategies for the surface design of catalysts and the development of photocatalytic hydrogen evolution.

Hierarchically Porous ZnO/g-C3N4 S-Scheme Heterojunction Photocatalyst for Efficient H2O2 Production.

The design of photocatalysts with hierarchical pore sizes is an effective method to improve mass transport, enhance light absorption, and increase specific surface area. Moreover, the construction of a heterojunction at the interface of two semiconductor photocatalysts with suitable band positions plays a crucial role in separating and transporting charge carriers. Herein, ZIF-8 and urea are used as precursors to prepare hierarchically porous ZnO/g-C3N4 S-scheme heterojunction photocatalysts through a two-step calcination method. This S-scheme heterojunction photocatalyst shows high activity toward photocatalytic H2O2 production, which is 3.4 and 5.0 times higher than that of pure g-C3N4 and ZnO, respectively. The mechanism of charge transfer and separation within the S-scheme heterojunction is studied by Kelvin probe, in situ irradiated X-ray photoelectron spectroscopy (ISI-XPS), and electron paramagnetic resonance (EPR). This research provides an idea of designing S-scheme heterojunction photocatalysts with hierarchical pores in efficient photocatalytic hydrogen peroxide production.

A quadruple-strategy of modification on carbon nitride boosts oxygen reduction for high performance photocatalytic hydrogen peroxide production.

This paper reports a quadruple-strategy for material design, simultaneously applying morphology control, group modification, defect engineering and alkali metal doping to the design of catalysts, and successfully constructing irregular clusters of carbon nitride (pMNK-CN) with excellent photogenerated carrier separation performance and structural stability. The pMNK-CN is an irregular flower cluster-like morphology with a nanosheet structure on the surface, and the repolymerization process of the prepolymer in the microvoid of the metal salt gives it an open pore structure. With the help of essential characterization, it was confirmed that the heptazine unit in the backbone underwent partial decomposition due to the etching of metal salts at high temperatures, reducing the overall polymerization and introducing cyano and nitrogen vacancies. Meanwhile, the potassium ion embedded in the lattice can induce the growth of ordered structures and thus improve the short-range order. The pMNK-CN possesses a hydrogen peroxide production efficiency of 240.0 µmol·g-1·h-1 in pure water, which is 31 times higher than that of bulk carbon nitride. And the apparent quantum efficiencies of pMNK-CN in the 380 and 420 nm bands are 17.5 % and 14.8 % in the presence of isopropanol. The effects of each modification strategies on the electronic structure of carbon nitride were investigated using First-Principles, and it was demonstrated that the multiple modification strategies synergistically enhanced the optical absorption, photogenerated charge separation efficiency, and lowered the reaction energy barrier, thus greatly contributing to the oxygen reduction to hydrogen peroxide performance.

Constructing the Sulfur-Doped CdO@In2O3 Nanofibers Ternary Heterojunction for Efficient Photocatalytic Hydrogen Production.

An S-doped CdO@In2O3 nanofiber was successfully designed by in-situ electrospinning along and subsequent calcination treatment. Under artificial sunlight illumination, the S/CdO@In2O3-25 displayed a superior photocatalytic hydrogen evolution rate of 4564.58 µmol·g-1·h-1, with approximately 22.0 and 1261.0-fold of those shown by the S/CdO and S/In2O3 samples, respectively. The experimental and theoretical analyses illustrate that the unique one-dimensional (1D) nanofiber morphology and rich oxygen vacancies optimized the electronic structure of the nanofibers and adsorption/desorption behaviors of reaction intermediates, contributing to the realization of the remarkable solar-to-H2 conversion efficiencies. Moreover, the staggered band structure and intimate contact heterointerfaces facilitate the formation of a type-II double charge-transfer pathway, promoting the spatial separation of photoexcited charge carriers. These results could inform the design of other advanced catalyst materials for photocatalytic reactions.

Br-/BrO--mediated highly efficient photoelectrochemical epoxidation of alkenes on α-Fe2O3.

Epoxides are significant intermediates for the manufacture of pharmaceuticals and epoxy resins. In this study, we develop a Br-/BrO- mediated photoelectrochemical epoxidation system on α-Fe2O3. High selectivity (up to >99%) and faradaic efficiency (up to 82 ± 4%) for the epoxidation of a wide range of alkenes are achieved, with water as oxygen source, which are far beyond the most reported electrochemical and photoelectrochemical epoxidation performances. Further, we can verify that the epoxidation reaction is mediated by Br-/BrO- route, in which Br- is oxidized non-radically to BrO- by an oxygen atom transfer pathway on α-Fe2O3, and the formed BrO- in turn transfers its oxygen atom to the alkenes. The non-radical mediated characteristic and the favorable thermodynamics of the oxygen atom transfer process make the epoxidation reactions very efficient. We believe that this photoelectrochemical Br-/BrO--mediated epoxidation provides a promising strategy for value-added production of epoxides and hydrogen.

Synthesis of MgNiCo LDH hollow structure derived from ZIF-67 as superb adsorbent for Congo red.

Adsorption materials with large specific surface area and porous structures exert a beneficial impact on improving the adsorption performance. In this work, MgNiCo LDH hollow structure (MNC HS) is fabricated through a simple one-step solvothermal method using ZIF-67 as the sacrificial template. Electron microscopy shows that the MNC HS retains the dodecahedral shape of ZIF-67. The as-prepared sample exhibits efficient adsorption for Congo red (CR) in water, which is due to the hierarchical structure and large specific surface area that provides more adsorption sites and electrostatic interaction. The CR adsorption process fits the pseudo-second-order model better by kinetics simulation; while Langmuir model is more accurate than Freundlich model in describing the adsorption isotherms of CR. The maximum adsorption capacity calculated by the Langmuir model can reach 1194.7 mg g-1, which is much higher than that of the sample MgNiCo LDH (MNC) synthesized by conventional methods. The cycle tests also show that the as-prepared adsorbent has good stability and recycling ability.

Anchoring highly-dispersed ZnCdS nanoparticles on NiCo Prussian blue Analogue-derived cubic-like NiCoP forms an S-scheme heterojunction for improved hydrogen evolution.

This study used a facile hydrothermal technique to obtain a novel ZnCdS/NiCoP S-scheme heterojunction for highly photocatalytic H2 generation, Notably, phosphatization was used to derive the cubic NiCoP from a Prussian blue analog ZnCdS nanoparticles are simple to disperse on the surface because NiCoP has a cubic characteristic, which easily transfers interface charges, and consequently accelerates surface reaction kinetics. Furthermore, the ZnCdS/NiCoP-3% composite exhibited the highest photocatalytic H2 generation performance of 582.98 µmol with an apparent quantum yield (AQY) of 7.93% at 450 nm in the lactic acid aqueous solution, which is approximately 4.16 and 500-fold higher than that of the pure ZnCdS and NiCoP, respectively. Additionally, outstanding photostability was achieved after 20h of the four cycling experiments. Consequently, the peachy photocatalytic hydrogen evolution can be imputed for establishing S-scheme heterojunction, maintaining doughty redox capacity and achieving spatial separation of charges, thereby vastly restraining the fast recombination of photoexcitation. Furthermore, the photoluminescence (PL) spectroscopy and hydroxyl radical (OH) capture experiments further proved the S-scheme mechanism. Therefore, this study provides a neoteric perspective establishing S-scheme photocatalytic systems for solar energy conversion.

Identifying the roles of imine and alkyne linkages in determining the photocatalytic hydrogen evolution over thiadiazole-based covalent organic frameworks.

Covalent organic frameworks (COFs) have emerged as an extremely promising material for photocatalytic water splitting for hydrogen production. However, their photocatalytic performance is seriously affected by the properties of their donors, acceptors and linkages. So far, few studies have been reported on the key roles of the linkages of a specific COF in improving its photocatalytic hydrogen production performance. Herein, this study designed and synthesized two thiadiazole-based COFs linked by imine and alkyne bonds. The results show that the photocatalytic hydrogen production performance of imine-linked COFs (TeTz-COF1) is 19.6 times higher than that of alkyne-linked COFs (TeTz-COF2). Impressively, TeTz-COF1 achieves an apparent quantum efficiency of 3.5% at 475 nm due to the presence of imine bonds. The experimental results confirm that TeTz-COF1 with imine linkages shows higher photocurrent density, lower photocurrent resistance, and longer fluorescence lifetime than TeTz-COF2 with alkyne linkages. Meanwhile, the well-defined density functional theory (DFT) calculations further suggest that both the imine bond and the acetylene bond belong to the HOMO orbitals. Particularly, the imine bonds endow TeTz-COF1 with more delocalized orbital occupation and smaller work functions, thus leading to its lower excited state energy, stronger carrier separation ability and faster electron migration capability. Both theoretical analysis and the experimental results prove that the presence of imine bonds in TeTz-COF1 can enable the efficient separation and fast transport of photogenerated carriers and high reducing ability of photogenerated electrons. This work may provide important guiding significance for the development of new COFs in the direction of photocatalytic water splitting for hydrogen production.

Dynamics of Photogenerated Charge Carriers in Inorganic/Organic S-Scheme Heterojunctions.

Step-scheme heterojunctions formed between two firmly bound photocatalysts facilitate charge separation due to interfacial charge transfer, which is usually illustrated by the gain or loss of electrons in the constituent photocatalysts characterized by in situ irradiated X-ray photoelectron spectroscopy. This technique provides a steady-state view of charge distribution but overlooks the transient and complex dynamics of charge transfer, trapping, and recombination. To provide a molecular-level and dynamic view of these processes, we investigated the behaviors of photogenerated charge carriers within an inorganic/organic TiO2/polydopamine S-scheme heterojunction using ultrafast transient absorption spectroscopy and time-resolved photoluminescence spectroscopy. We found the interfacial charge transfer within the step-scheme heterojunction occurred at a smaller shorter time scale than recombination, leading to efficient charge separation. Moreover, the charge-discharge property of polydopamine induces electron backflow, which should be avoided in practical photocatalytic applications. The composite showed higher photocatalytic H2O2-production activities due to faster H2O2 formation and suppressed H2O2 decomposition.

A synergistic hydrothermal-deep eutectic solvents (DES) pretreatment for acquiring xylooligosaccharides and lignin nanoparticles from Eucommia ulmoides wood.

To achieve an effective deconstruction for preparation of xylooligosaccharides (XOS) and lignin nanoparticles (LNPs) from Eucommia ulmoides, a synergistic pretreatment was successfully developed. Herein, the hemicelluloses were preferentially dissociated in acetic acid-catalyzed hydrothermal pretreatment (HTP) for preparation of XOS, and the hydrothermally-pretreated substrate was then subjected to deep eutectic solvents (DES) delignification for fabrication of LNPs. Results showed that the optimal yield (33.88% based on xylan) of XOS is obtained under the given HTP condition (170 °C, 0.5 h). NMR characterization showed that the linkages of lignin were mainly composed of ß-O-4, ß-ß, ß-5, etc. Besides, GPC analysis showed that the molecular weight of DES lignin fractions was lower (1130-1200 g/mol) than those of corresponding parent lignin fractions (8500-9620 g/mol). Further TEM characterization indicated that the optimal LNPs fraction has a narrow size distribution and the corresponding size is ranged from 60 to 110 nm. In short, the synergistic pretreatment could be used as a green and cost-effective approach for the development of bio-based chemicals and biomaterials from Eucommia ulmoides biomass.

Variation in IGHMBP2 is not associated with IgA nephropathy in independent studies of UK Caucasian and Chinese Han patients.

BACKGROUND: IgA nephropathy is a major cause of end-stage renal disease worldwide. Its aetiology is poorly understood but there is good evidence for a major genetic component, although to date, no gene has been conclusively identified. We describe a new UK multicentre DNA collection assembled to investigate this. A Japanese genome-wide analysis recently reported that common genetic variation in immunoglobulin mu-binding protein 2 (IGHMBP2) was associated with IgA nephropathy. We sought to replicate this using the new UK collection, and through an independent parallel analysis of a Han Chinese population. METHODS: In the UK collection, haplotype-tagging (tag) single-nucleotide polymorphisms (SNPs) and haplotypes were analysed in a case-control study (349 cases, 605 controls) and family-based analysis (162 complete and 23 partially complete family trios), which was performed using the transmission disequilibrium test. In parallel, 663 cases of IgA nephropathy and 663 controls from a Chinese population were analysed: coding and flanking regions of the gene were re-sequenced in a subset, and SNP and haplotype association analysis was performed in the whole collection using the identified tagSNPs and all the coding and exonic flanking SNPs. RESULTS: Case-control studies in UK and Chinese populations, and family-based tests in the UK population provided no evidence for association between variation in IGHMBP2 and IgA nephropathy. The A allele of SNP G34448A was not present in the UK collection. It was present but not associated with the disease in the Chinese population. CONCLUSION: Variation in IGHMBP2 does not confer significant susceptibility to IgA nephropathy in UK Caucasian or Chinese Han populations.

TRAC variants associate with IgA nephropathy.

The T cell receptor alpha constant gene (TRAC) encodes the constant region of the alpha chain for the T cell receptor, and the association of its gene variants with IgA nephropathy remains controversial. The authors resequenced the gene in 100 patients with IgA nephropathy and 100 controls, tested its linkage disequilibrium pattern, constructed haplotypes, and performed association and functional studies. First, the association between TRAC variants and IgA nephropathy was tested in 704 patients and 704 controls. Next, these 704 patients were divided into two independent datasets--310 with family member(s) and 394 single patients--to test the association separately. Results showed that the gene is located in a recombination hot spot, with nine linkage disequilibrium blocks within a 6.9-kb region. There is a hypervariable region with six single-nucleotide polymorphisms (SNPs) in an 85-bp stretch in intron 1. We identified multiple SNPs and two haplotypes that associate with IgA nephropathy (P = 0.0000013-0.0096 by logistic regression for SNPs; P = 0.0003 and P = 0.0398 for haplotype associations). The family-based study replicated both haplotype findings, and the 394 single-patient case-control study replicated the association with haplotype 1 (P = 0.0033). The overtransmitted/observed haplotypes demonstrated reduced transcription activity compared with the undertransmitted/observed haplotypes. In conclusion, this study suggests an association between TRAC variants and susceptibility to IgA nephropathy.

Activated carbon supported TiO2-photocatalysis doped with Fe ions for continuous treatment of dye wastewater in a dynamic reactor.

Fe-doped TiO2 coated on activated carbon (Fe-TiO2/AC, FTA) composites were prepared by an improved sol-gel method and characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray diffractometry, inductively coupled plasma mass spectrometry and BET surface area analysis. Obtained FTA composites were applied to the continuous treatment of dye wastewater in a dynamic reactor. The effects of Fe ion content, catalyst content, UV-lamp power and flowrate of the continuous treatment of dye wastewater on degradation efficiency were analyzed to determine the optimum operating conditions of dye wastewater degradation. Continuous photocatalytic experiments provided interesting results that VIFTA had a high chemical oxygen demand (COD) removal rate compared with TiO2, Fe doped TiO2 (FT) and TiO2 coated on activated carbon (TA). In particular, when using the FTA catalyst with a Fe ion content of 0.33%, the kinetic content (k = 0.0376) of COD removal was more than the sum of both TA (0.0205) and 0.33% FT (0.0166). FTA showed a high photoactivity because of a synergistic effect between Fe ions and AC on TiO2, which is higher than the individual effects of AC or Fe ions on TiO2. Additionally, for the photocatalytic degradation of dye wastewater, the optimum Fe ion content, catalyst content, UV-lamp power and flowrate were 0.33%, 6 g/L, 60 W (two lamps) and 300 mL/hr, respectively. An investigation of catalyst reuse revealed that the 0.33% FTA showed almost no deactivation in photocatalytic degradation of naturally treated wastewater.

Geographic Authentication of Eucommia ulmoides Leaves Using Multivariate Analysis and Preliminary Study on the Compositional Response to Environment.

To explore the influences of different cultivated areas on the chemical profiles of Eucommia ulmoides leaves (EUL) and rapidly authenticate its geographical origins, 187 samples from 13 provinces in China were systematically investigated using three data fusion strategies (low, mid, and high level) combined with two discrimination model algorithms (partial least squares discrimination analysis; random forest, RF). RF models constructed by high-level data fusion with different modes of different spectral data (Fourier transform near-infrared spectrum and attenuated total reflection Fourier transform mid-infrared spectrum) were most suitable for identifying EULs from different geographical origins. The accuracy rates of calibration and validation set were 92.86% and 93.44%, respectively. In addition, climate parameters were systematically investigated the cluster difference in our study. Some interesting and novel information could be found from the clustering tree diagram of hierarchical cluster analysis. The Xinjiang Autonomous Region (Region 5) located in the high latitude area was the only region in the middle temperate zone of all sample collection areas in which the samples belonged to an individual class no matter their distance in the tree diagram. The samples were from a relatively high elevation in the Shennongjia Forest District in Hubei Province (>1200 m), which is the main difference from the samples from Xiangyang City (78 m). Thus, the sample clusters from region 9 are different from the sample clusters from other regions. The results would provide a reference for further research to those samples from the special cluster.

Targeting the CD134-CD134L interaction using anti-CD134 and/or rhCD134 fusion protein as a possible strategy to prevent lupus nephritis.

Lupus nephritis (LN) is characterized by an increased upregulation of Th1. This study was undertaken to evaluate the role of CD134 in cytokine production in peripheral blood mononuclear cells (PBMCs) from subjects with LN. Percentages of IFN-gamma- (Th1), IL-4-, and IL-10- (Th2) producing cells within the PBMC CD4+ T cell population of LN subjects were found to be higher than those of healthy subjects. Stimulation of PBMC from LN subjects with anti-CD3 epsilon mAb/rIL-2 resulted in further increases in cytokine production. Stimulation in the presence of anti-CD134 mAb resulted in reduced IL-4 and IL-10 production; however, it also resulted in increased IFN-gamma production. Stimulation in the presence of the fusion protein rhCD134:Fc resulted in decreased production of all three cytokines. The possibilities that anti-CD134 therapy may control the extent of IL-4- and IL-10-mediated damage in active LN and that rhCD134:Fc therapy may prevent occurrence of LN are discussed.

Conical nanofluidic channel for selective quantitation of melamine in combination with ß-cyclodextrin and a single-walled carbon nanotube.

Amine group-bearing small molecules tend to adsorb onto the nanochannel surfaces, which degrades the efficiency of nanochannel sensors. In this study, we utilized host-guest knowledge to eliminate the influence of excessive small molecules. In combination with single-walled carbon nanotubes (SWNTs), ß-cyclodextrin (ß-CD) provided an excellent sensing performance for the conical nanochannel coated with polyethyleneimine (PEI) and zirconium ion (Zr4+). By taking detection of melamine as a prototype, the as-prepared nanochannel could selectively detect melamine-elicited double-stranded DNA (dsDNA). Both excessive melamine and single-stranded DNA were removed via the addition of ß-CD and SWNTs. The nanochannel sensing platform for the detection of melamine has a detection limit of as low as 4.3 nM with a suitable sensitivity, an excellent reproducibility and stability. Therefore, it is highly promising that a nanochannel sensor based on ion current rectification (ICR) can be used to detect other possible targets.