Visualizing interfacial collective reaction behaviour of Li-S batteries.

Benefiting from high energy density (2,600 Wh kg-1) and low cost, lithium-sulfur (Li-S) batteries are considered promising candidates for advanced energy-storage systems1-4. Despite tremendous efforts in suppressing the long-standing shuttle effect of lithium polysulfides5-7, understanding of the interfacial reactions of lithium polysulfides at the nanoscale remains elusive. This is mainly because of the limitations of in situ characterization tools in tracing the liquid-solid conversion of unstable lithium polysulfides at high temporal-spatial resolution8-10. There is an urgent need to understand the coupled phenomena inside Li-S batteries, specifically, the dynamic distribution, aggregation, deposition and dissolution of lithium polysulfides. Here, by using in situ liquid-cell electrochemical transmission electron microscopy, we directly visualized the transformation of lithium polysulfides over electrode surfaces at the atomic scale. Notably, an unexpected gathering-induced collective charge transfer of lithium polysulfides was captured on the nanocluster active-centre-immobilized surface. It further induced an instantaneous deposition of nonequilibrium Li2S nanocrystals from the dense liquid phase of lithium polysulfides. Without mediation of active centres, the reactions followed a classical single-molecule pathway, lithium polysulfides transforming into Li2S2 and Li2S step by step. Molecular dynamics simulations indicated that the long-range electrostatic interaction between active centres and lithium polysulfides promoted the formation of a dense phase consisting of Li+ and Sn2- (2 < n ≤ 6), and the collective charge transfer in the dense phase was further verified by ab initio molecular dynamics simulations. The collective interfacial reaction pathway unveils a new transformation mechanism and deepens the fundamental understanding of Li-S batteries.

A Universal Approach for Controllable Synthesis of Homogeneously Alloyed PtM Nanoflowers toward Enhanced Methanol Oxidation.

Platinum (Pt)-based alloys have received considerable attention due to their compositional variability and unique electrochemical properties. However, homogeneous element distribution at the nanoscale, which is beneficial to various electrocatalytic reactions, is still a great challenge. Herein, a universal approach is proposed to synthesize homogeneously alloyed and size-tunable Pt-based nanoflowers utilizing high gravity technology. Owing to the significant intensification of micro-mixing and mass transfer in unique high gravity shearing surroundings, five typical binary/ternary Pt-based nanoflowers are instantaneously achieved at room temperature. As a proof-of-concept, as-synthesized Platinum-Silver nanoflowers (PtAg NFs) demonstrate excellent catalytic performance and anti-CO poisoning ability for anodic methanol oxidation reaction with high mass activity of 1830 mA mgPt -1, 3.5 and 3.2 times higher than those of conventional beaker products and commercial Pt/C, respectively. The experiment in combination with theory calculations suggest that the enhanced performance is due to additional electronic transmission and optimized d-band center of Pt caused by high alloying degree.

Redox/pH Dual-Responsive Fluorescent Nanoparticles for Intelligent Pesticide Release and Visualization in Gray Mold Disease Synergistic Control.

An intelligent delivery nanoformulation could enhance the utilization efficacy, uptake, and translocation of pesticides in plants. Herein, a redox/pH-triggered and fluorescent smart delivery nanoformulation was designed and constructed by using hollow mesoporous organosilica nanoparticles (HMONs) and ZnO quantum dots as the nanocarrier and capping agent, respectively. Boscalid was further loaded to generate Boscalid@HMONs@ZnO with a loading rate of 9.8% for controlling Botrytis cinerea (B. cinerea). The quantity of boscalid released by Boscalid@HMONs@ZnO in a glutathione environment or at pH 3.0 was 1.3-fold and 1.9-fold higher than that in a neutral condition. Boscalid@HMONs@ZnO has 1.7-fold the toxicity index of boscalid technical against B. cinerea in antifungal experiments. Pot experiments revealed that the efficacy of Boscalid@HMONs@ZnO was significantly enhanced more than 1.27-fold compared to commercially available water-dispersible granules of boscalid. Due to the fluorescence properties of Boscalid@HMONs@ZnO, pesticide transport's real-time monitoring of pesticide translocation in tomato plants could be observed by confocal laser scanning microscopy. Fluorescence images revealed that HMONs@ZnO had been effectively transported via treated leaves or roots in tomato plants. This research showed the successful application of HMONs@ZnO as a nanocarrier for controlling disease and offered an effective avenue to explore the real-time tracking of pesticide translocation in plants.

Greatly Intensified Guest Exchange Strategy for Highly-Efficient Activation of Metal-Organic Frameworks.

The preservation and accessibility of pores are prerequisites to the application of metal-organic frameworks (MOFs). Activation is a key step to eliciting rich features of pores, but it needs a repeated solvent-exchange process which is tedious and time/cost-consuming. Herein, a facile strategy for highly-efficient activation of MOFs utilizing rotating packed bed is proposed. With the tremendous enhancement of molecular mixing and mass transfer in high-gravity and strong-shearing surrounding, nine representative MOFs are completely activated within 2 h without structural change. Compared with conventional process, this activation displays surprising efficiency by accelerating the diffusion of solvents and redissolution of residual reactants in the pores. The complete activation time can be significantly shortened by over 90%. As a proof-of-concept, the methane storage of as-activated UiO-66 is five times that of as-synthesized UiO-66. This strategy provides a potential platform with industrial worth for the activation of MOF materials with ultra-high efficiency and versatility.

Degradable PDA@PNIPAM-TA Nanocomposites for Temperature- and NIR light-Controlled Pesticide Release.

Controlled pesticide delivery systems offer many distinctive advantages over conventional pesticide formulations. In this work, degradable poly(N-isopropylacrylamide) (PNIPAM)-tannic acid (TA) microgels and multifunctional PDA@PNIPAM-TA nanocomposites were prepared in a high-gravity rotating packed bed reactor (RPB) for smart pesticide delivery and release. The as-prepared microgels and nanocomposites showed reversible temperature-dependent swelling/deswelling behavior and irreversible pH-induced degradation. A dynamic contact angle test suggested that the introduction of TA and PDA into the PNIPAM matrix could enhance foliar adhesion and deposition efficiency. The nanocomposites were further used for the encapsulation and delivery of imidacloprid (IMI) to protect it from rapid photolysis and improve its pest-control efficiency. Their thermoresponsive behavior as well as pesticide loading capacity could be tuned by tailoring the PNIPAM-TA shell thickness, which could be varied by the NIPAM amount. The release rate of IMI from the core/shell nanocomposites was positively correlated with environmental temperature and near-infrared (NIR) light, which was adaptive to the positive temperature-dependent toxicity correlation of IMI and the increasing trend of pests under high temperature. The cumulative release of IMI was 23.5% at 25 °C, while it was 81.2% at 40 °C after 24 h of incubation, and the release rate was greatly enhanced under NIR irradiation. The results indicated that the facile control of pesticide release could be realized by regulating environmental conditions. This work also provides an idea for using high-gravity technology to conveniently construct a smart, effective, and environmentally friendly pesticide delivery system for sustainable crop protection.

Redox/Near-Infrared Dual-Responsive Hollow Mesoporous Organosilica Nanoparticles for Pesticide Smart Delivery.

Extremely inefficient utilization of pesticides has prompted a study of low-cost, sustainable, and smart application systems. Herein, as a promising pesticide nanocarrier, hollow mesoporous organosilica nanoparticles (HMONs) were first synthesized by using inexpensive CaCO3 nanoparticles as the hollow templates. A redox/near-infrared light dual-triggered pesticide release system was further achieved via loading avermectin (AVM) into the HMONs and coating a layer of polydopamine (PDA). The as-prepared AVM@HMONs@PDA displays a favorable pesticide load capability (24.8 wt %), outstanding photothermal performance, and high adhesion to leaves. In addition, with glutathione (GSH), the AVM cumulative release from AVM@HMONs@PDA was 3.5 times higher than that without GSH. Under ultraviolet light irradiation, the half-life of AVM@HMONs@PDA was prolonged by 17.0-fold compared to that of the AVM technical. At day 21 after treatment in the insecticidal activity, the median lethal concentrations (LC50) values displayed that the toxicity of AVM@HMONs@PDA for Panonychus citri (McGregor) was enhanced 4.0-fold compared with the commercial emulsifiable concentrate. In the field trial, at day 28 after spraying, AVM@HMONs@PDA was significantly more control effective than AVM-EC in controlling the P. citri (McGregor), even at a 50% reduced dosage. Moreover, HMONs@PDA was safe for crops. This research presents a novel preparation approach for HMONs, and it also offers a promising nanoplatform for the precise release of pesticides.

In Situ TEM Observation of Stagnant Liquid Layer Activation in Nanochannel.

The kinetics of mass transfer in a stagnant fluid layer next to an interface govern numerous dynamic reactions in diffusional micro/nanopores, such as catalysis, fuel cells, and chemical separation. However, the effect of the interplay between stagnant liquid and flowing fluid on the micro/nanoscopic mass transfer dynamics remains poorly understood. Here, by using liquid cell transmission electron microscopy (TEM), we directly tracked microfluid unit migration at the nanoscale. By tracking the trajectories, an unexpected mass transfer phenomenon in which fluid units in the stagnant liquid layer migrated two orders faster during gas-liquid interface updating was identified. Molecular dynamics (MD) simulations indicated that the chemical potential difference between nanoscale liquid layers led to convective flow, which greatly enhanced mass transfer on the surface. Our study opens up a pathway toward research on mass transfer in the surface liquid layers at high spatial and temporal resolutions.

Polyacetylene Isomers Isolated from Bidens pilosa L. Suppress the Metastasis of Gastric Cancer Cells by Inhibiting Wnt/ß-Catenin and Hippo/YAP Signaling Pathways.

(E)-7-Phenyl-2-hepten-4,6-diyn-1-ol (1) and (Z)-7-Phenyl-2-hepten-4,6-diyn-1-ol (2) are isomeric natural polyacetylenes isolated from the Chinese medicinal plant Bidens pilosa L. This study first revealed the excellent anti-metastasis potential of these two polyacetylenes on human gastric cancer HGC-27 cells and the distinctive molecular mechanisms underlying their activities. Polyacetylenes 1 and 2 significantly inhibited the migration, invasion, and adhesion of HGC-27 cells at their non-toxic concentrations in a dose-dependent manner. The results of a further mechanism investigation showed that polyacetylene 1 inhibited the expressions of Vimentin, Snail, ß-catenin, GSK3ß, MST1, YAP, YAP/TAZ, and their phosphorylation, and upregulated the expression of E-cadherin and p-LATS1. In addition, the expressions of various downstream metastasis-related proteins, such as MMP2/7/9/14, c-Myc, ICAM-1, VCAM-1, MAPK, p-MAPK, Sox2, Cox2, and Cyr61, were also suppressed in a dose-dependent manner. These findings suggested that polyacetylene 1 exhibited its anti-metastasis activities on HGC-27 cells through the reversal of the EMT process and the suppression of the Wnt/ß-catenin and Hippo/YAP signaling pathways.

A meta-analysis showing the quantitative evidence base of perineural nalbuphine for wound pain from upper-limb orthopaedic trauma surgery.

The adjuvant effectiveness of nalbuphine in context of brachial plexus block (BPB) in patients undergoing upper-limb orthopaedic trauma surgery has remained uncertain. The purpose of this meta-analysis was to evaluate the analgesic benefit of mixing nalbuphine into local anaesthetics in BPB for wound pain from upper-limb trauma surgery. Primary outcome was the duration of analgesia. Seventeen trials (1104 patients) were analysed. Patients receiving nalbuphine have an increased weighted mean difference (WMD) 95% confidence interval of the duration of analgesia by 186.91 minutes (133.67 to 240.16) (P < 0.001). Compared to placebo, nalbuphine shorten the onset time of sensory and motor block by WMD of 2.59 (1.27 to 3.92) and 3.06 minutes (1.65 to 4.48) (P < 0.001), respectively. Meanwhile, nalbuphine prolonged the durations of sensory and motor block (P < 0.001). Qualitative and quantitative synthesis revealed no differences with regard to the outcomes related to side-effects. There is moderate-quality evidence that the addition of nalbuphine to local anaesthetics for BPB in patients undergoing upper-limb orthopaedic trauma surgery significantly prolongs the duration of analgesia, while preserving a similar safety-profile compared with local anaesthetics alone. However, these benefits should be further weighed against nalbuphine-related neurological safety in future studies.

Effects of different frequencies of Er:YAG laser on the bonding properties of zirconia ceramic.

The effects of Er:YAG laser with different frequencies on zirconia ceramic's bonding properties were studied. In total, 42 Y-TZP (yttrium-stabilized tetragonal zirconia polycrystals, UPCERA ST) with 3 mm × 3 mm × 2 mm divided into 6 groups (n = 7): control (C), sandblasting (SB), and Er:YAG laser (A1-A4), which the frequencies correspond to 5 Hz, 10 Hz, 15 Hz, and 20 Hz, IPS e.max Press ceramics were B. Scanning electron microscope (SEM) images were recorded. The ceramics were bonded to enamel from extracted teeth. After being constantly stored at 37 ℃ for 24 h, the shear test was performed with a universal testing machine. Stereomicroscope evaluated fracture modes. Stereomicroscope evaluated fracture modes. Data were analyzed by SPSS26.0 statistical software; the standard was P = 0.05. (1) The SEM showed the surface of A1-A4 became rough compared with C. (2) The shear test showed that the highest bonding strength for B was 13.15 ± 2.97 MPa, followed by SB was 7.78 ± 0.97 MPa, and A2 was 7.13 ± 0.75 MPa. However, there was no significant difference between SB and A2 (P > 0.05). Fracture modes of C were the interface fracture of Y-TZP and resin adhesive; most of A1-A4 and SB also were interface fracture, a few mixed fractures, and cohesion fracture of resin adhesive; B were all mixed fracture. Er:YAG laser with 10 Hz could be used as an alternative to sandblasting with Al2O3 for surface modification of Y-TZP to increase the bonding strength.

Nigrosporins B, a Potential Anti-Cervical Cancer Agent, Induces Apoptosis and Protective Autophagy in Human Cervical Cancer Ca Ski Cells Mediated by PI3K/AKT/mTOR Signaling Pathway.

Nigrosporins B, an anthraquinone derivative obtained from the secondary metabolites of marine fungus Nigrospora oryzae. In this study, we characterized the distinctive anti-cancer potential of Nigrosporins B in vitro and underlying molecular mechanisms in human cervical cancer Ca Ski cells for the first time. The results of MTT assay showed that Nigrosporins B significantly inhibited the proliferation of multiple tumor cells in a dose-dependent manner, especially for the Ca Ski cells with an IC50 of 1.24 µM. Nigrosporins B exerted an apoptosis induction effect on Ca Ski cells as confirmed by flow cytometry, AO/EB dual fluorescence staining, mitochondrial membrane potential analysis and western blot assay. In addition, Nigrosporins B induced obvious autophagy accompanied with the increase of autophagic vacuoles and the acceleration of autophagic flux as indicated by Cyto-ID staining, mRFP-GFP-LC3 adenovirus transfection and western blot analysis. Interestingly, the combination of Nigrosporins B with the three autophagy inhibitors all significantly enhanced the cytotoxicity of Nigrosporins B on Ca Ski cells, indicating that the autophagy induced by Nigrosporins B might protect Ca Ski cells from death. Furthermore, we found that Nigrosporins B inhibited the phosphorylation of PI3K, AKT, mTOR molecules and increased the protein expression levels of PTEN and p-AMPKα in a dose-dependent manner, suggesting that Nigrosporins B induced apoptosis and protective autophagy through the suppression of the PI3K/AKT/mTOR signaling pathway. Together, these findings revealed the anti-cervical cancer effect of Nigrosporins B and the underlying mechanism of action in Ca Ski cells, it might be as a promising alternative therapeutic agent for human cervical cancer.

Surface Engineering of Titanium Dioxide Nanoparticles for Silicone-Based Transparent Hybrid Films with Ultrahigh Refractive Indexes.

We report a newly developed surface engineering approach for TiO2 nanoparticles toward transparent TiO2/silicone nanocomposites with high refractive index (RI) values. Zirconate coupling agents are adopted on the TiO2 nanoparticles for surface passivation and to enhance the dispersibility of the nanoparticles in organic substrates. The modified TiO2 nanoparticles can be uniformly dispersed in silicone, forming transparent hybrid films with an ultrahigh RI of 2.01. The preparation technique of colloidal TiO2 and polymer-based nanocomposites is simple and suitable for scalable production, which is promising for expanding the application of TiO2 materials in photonic devices.

ATG 4B Serves a Crucial Role in RCE-4-Induced Inhibition of the Bcl-2-Beclin 1 Complex in Cervical Cancer Ca Ski Cells.

RCE-4, a steroidal saponin isolated from Reineckia carnea, has been studied previously and has exhibited promising anti-cervical cancer properties by inducing programmed cell death (PCD) of Ca Ski cells. Considering the cancer cells developed various pathways to evade chemotherapy-induced PCD, there is, therefore, an urgent need to further explore the potential mechanisms underlying its actions. The present study focused on targeting the Bcl-2-Beclin 1 complex, which is known as the key regulator of PCD, to deeply elucidate the molecular mechanism of RCE-4 against cervical cancer. The effects of RCE-4 on the Bcl-2-Beclin 1 complex were investigated by using the co-immunoprecipitation assay. In addition, autophagy-related genes (ATG) were also analyzed due to their special roles in PCD. The results demonstrated that RCE-4 inhibited the formation of the Bcl-2-Beclin 1 complex in Ca Ski cells via various pathways, and ATG 4B proteins involved in this process served as a key co-factor. Furthermore, based on the above, the sensitivity of RCE-4 to Ca Ski cells was significantly enhanced by inhibiting the expression of the ATG 4B by applying the ATG 4B siRNA plasmid.

[Integrin activation, focal adhesion maturation and tumor metastasis].

Integrins are a large family of heterodimeric cell adhesion molecules composed of α and ß subunits. Through interaction with their specific ligands, integrins mediate cell-cell and cell-extracellular matrix interactions. Via outside-in signaling, integrins can recruit cytoplasmic proteins to their intracellular domains and then cluster into supramolecular structures and trigger downstream signaling. Integrin activation is associated with a global conformation rearrangement from bent to extended in ectodomains and the separation of α and ß subunit cytoplasmic domains. During cell migration, integrins regulate the focal adhesion dynamics and transmit forces between the extracellular matrix and the cell cytoskeleton. In tumor microenvironment, integrins on multiple kinds of cells could be activated, which modulates cell migration into tumor and contributes to angiogenesis and tumor metastasis. Here, we review the mechanism of integrin activation, dynamics of focal adhesions during cell migration and tumor metastasis.

A General Strategy for Instantaneous and Continuous Synthesis of Ultrasmall Metal-Organic Framework Nanoparticles.

Ultrasmall metal-organic frameworks (MOFs) may generate unique properties to expand the scope of applications. However, the synthesis is still a great challenge. Herein, we propose a strategy to synthesize ultrasmall MOFs by high gravity technology. With the aid of tremendous intensification of molecular mixing and mass transfer in high-gravity field, six typical MOFs were obtained instantaneously in a continuous way. These samples are monodispersed with sub-5 nm in size, smaller than the previously reported values and even close to the length of one crystal unit cell. As a proof-of-concept, catalytic activity for Knoevenagel reaction can be significantly enhanced using ultrasmall ZIF-8. Conversion time of benzaldehyde was decreased by 94 % or 75 % compared to those using conventional or hierarchically porous ZIF-8. More importantly, this approach is readily scalable with the highest space-time yield for nano-MOFs, which may promote the convenient synthesis and practical applications of ultrasmall MOFs in large-scale.

Involvement of activin a receptor type 1 (ACVR1) in the pathogenesis of primary focal hyperhidrosis.

The pathogenesis of primary focal hyperhidrosis (PFH) is still not clear. PFH is thought to be a genetic disease. Whether activin A receptor type 1 (ACVR1) is involved in the pathogenesis of PFH is unknown. In this study, the expression of ACVR1 in sweat glands of patients with PAH was detected by western blot and immunofluorescence. The primary sweat gland cells obtained from primary axillary hyperhidrosis (PAH) patients were transfected with acvr1 vector. Cell proliferation, apoptosis and cell cycling of gland cells were measured after transfection with acvr1 vector. The mRNA and protein expression of aquaporin 5 (AQP5) and Na:K:2Cl Cotransporter 1 (NKCC1/SLC12A2) were detected. Our data showed that ACVR1 expression in axillary sweat gland tissue of PAH patients was significantly higher than that of normal control group. The function of ACVR1 was further investigated in the gland cells obtained from PAH patients. Compared with NC group, ACVR1 overexpression significantly promoted the proliferation of sweat gland cells and inhibited the apoptosis of sweat gland cells. Meanwhile, ACVR1 overexpression significantly reduced the percentage of cells in G0/G1 and G2/M phases, and increased the percentage of cells in S phase. In addition, ACVR1 overexpression significantly promoted the expression of AQP5 and NKCC1 at both mRNA and protein levels. Together, ACVR1 expression is related to PFH and ACVR1 overexpression can promote the proliferation of sweat gland cells and inhibit apoptosis by promoting the expression of AQP5 and NKCC1.

Liquid Marbles in Liquid.

Traditional liquid marbles (LMs), liquid droplets encapsulated by hydrophobic particles at the liquid-gas interface, are restricted by their short lifetime and low heat transfer efficiency. Herein, a new paradigm for LMs immersed in various liquid mediums with massive enhanced heat transfer and spatial recognition is designed; without compromising the structural integrity, the lifetime of the liquid marbles in liquid (LMIL) is extended by ≈1000 times compared to classical LMs in air or naked droplets in organic reagents. The LMIL shows promising reverse structural re-configurability while under external stimuli and maintaining their functionality for a very long period of time (≈weeks). These superior behaviors are further exploited as a miniature reactor with prolonged lifetimes and excellent temperature control, combined with its feasible operation, new opportunities will open up in the advanced chemical and biomedical engineering fields. It is also shown that LMIL can be applied in methylene blue degradation and 3D in-vitro yeast cell cultures. These findings have important implications for real-world use of LMs, with a number of applications in cell culture technology, lab-in-a-drop, polymerization, encapsulation, formulation, and drug delivery.

Separation of micro and sub-micro diamagnetic particles in dual ferrofluid streams based on negative magnetophoresis.

In the present study, we numerically demonstrate an approach for separation of micro and sub-micro diamagnetic particles in dual ferrofluid streams based on negative magnetophoresis. The dual streams are constructed by an intermediate sheath flow, after which the negative magnetophoretic force induced by an array of permanent magnets dominates the separation of diamagnetic particles. A simple and efficient numerical model is developed to calculate the motions of particles under the action of magnetic field and flow field. Effects of the average flow velocity, the ratio of sheath fluid flow to sample fluid flow, the number of the magnet pair as well as the position of magnet pair are investigated. The optimal parametric condition for complete separation is obtained through the parametric analysis, and the separation principle is further elucidated by the force analysis. The separation of smaller micro and sub-micro diamagnetic particles is finally demonstrated. This study provides an insight into the negative magnetophoretic phenomenon and guides the fabrication of feasible, low-cost diagnostic devices for sub-micro particle separation.

Classification of induced malaria case in an elimination setting: investigation of transfusion-transmitted malaria cases.

BACKGROUND: Since the National Malaria Elimination Action Plan was launched in China in 2010, local malaria transmission has decreased rapidly. Zero indigenous cases were reported since 2017. However, after 2010, the proportion of imported cases in China increased from 45.7% in 2010 to 99.9% in 2016, and almost all provinces of China have reported imported cases in recent years. Prevention of the reintroduction of malaria into China is crucial for the maintenance of its malaria-free status. Hence, it is of utmost importance to correctly identify the source of malaria infections within the country. CASE INTRODUCTION AND RESPONSE: In 2016 and 2017, three laboratory-confirmed cases of malaria caused by Plasmodium falciparum were identified in patients with no previous travel history to endemic areas were reported in Jiangsu Province, China, where malaria due to P. falciparum was eliminated about 30 years ago. These were diagnosed after 41, 31 and 39 days of seeking treatment, respectively, and all of them had received blood transfusions. Further investigations indicated that two of the cases had received blood from foreign students (from Indonesia and Ghana), and the other had received blood from an individual who had worked in Equatorial Guinea. All three blood donors were traced, and found to be carrying asymptomatic P. falciparum infections by microscopic examination and PCR. Furthermore, five polymorphic microsatellite markers (C1M4, C4M62, C13M13, C14M17, and C13M63) were typed and used to link parasites from the donors with those of the transfusion-receiving patients. CONCLUSIONS: Three transfusion-transmitted malaria cases were identified in China, all of which were due to the transfusion of blood donated by individuals who had contracted malaria outside the country. These cases can provide a reference for those faced with similar challenges in malaria case identification and classification in other regions. In addition, a stricter screening policy including the use of appropriate detection methods for malaria parasites should be developed and adopted for blood donation in regions undergoing malaria elimination.

Surfactant-Free Aqueous Dispersions of Shape- and Size-Controlled Zirconia Colloidal Nanocrystal Clusters with Enhanced Photocatalytic Activity.

Colloidal nanocrystal clusters (CNCs) are formed by clustering nanocrystals into secondary structures, which represent a new class of materials and have attracted considerable attention, owing to their unique collective properties and novel functionalities achieved from the ensembles in addition to the properties of each individual subunit. Here, we design a simple route to prepare aqueous dispersions of highly stable ZrO2 CNCs with tunable shape and size without modification. ZrO2 CNCs are composed of many ZrO2 nanocrystals each with a size of about 7 nm and possess a mesoporous structure. Both cube-like and star-like shapes of CNCs can be achieved by using different alkaline sources, while the size of CNCs can be adjusted by changing the hydrothermal time. The as-prepared aqueous dispersions of ZrO2 CNCs display an enhanced photocatalytic activity in the degradation of rhodamine B (RhB), compared with ZrO2 nanodispersions. More interestingly, star-like ZrO2 CNCs show better photocatalytic degradation properties than those of cube-like counterparts and even commercial P25. Furthermore, ZrO2 CNCs are easily recycled and can be used for the degradation of a range of dye systems.