Carbon Nanodot-Decorated Ag@SiO₂ Nanoparticles for Fluorescence and Surface-Enhanced Raman Scattering Immunoassays

A novel immunoassay protocol was demonstrated by the combination of fluorescent carbon nanodots (CNDs) and Ag@SiO₂ surface-enhanced Raman scattering (SERS) tag nanoparticles into ensembles for a bifunctional nanoplatform. The CND-decorated Ag@SiO₂ nanoparticles were constructed for sensitive fluorescence and SERS immunoassays. The silica shell thickness and amount of Ag@SiO₂ nanoparticles were optimized for availability of strong fluorescence emission. The considerably large Raman scattering cross section of in situ-generated actual Raman reporter, 4,4′-dimercaptoazobenzene, from the apparent reporter <i>p</i>-aminothiophenol modified on the surfaces of Ag nanoparticles upon illumination of laser compensated for the reduction of SERS signals resulting from silica coating to a great degree. The antibody-modified bifunctional nanoparticles were captured by antibody-modified quartz slides in the presence of antigens in the sandwich structures for fluorescence and SERS immunoassays. The bifunctional nanoparticles could be used not only as bimodal probes for biodetection but also as bimodal tracers for bioimaging

The Energy Release Characteristics of Shock-Induced Chemical Reaction of Al/Ni Composites

In this paper, the energy release mechanism of shock-induced chemical reaction (SICR) of Al/Ni composites was investigated. The Al/Ni composites with two additives, namely Teflon (PTFE) and copper (Cu), were considered in both theoretical calculations and experiments to investigate their influence on SICR characteristics of Al/Ni composites system. Assuming the SICR process is controlled by shock temperature rising in the materials, the reaction efficiency of Al/Ni composites was calculated by Arrhenius reaction rate and Avrami–Erofeev reaction models. Hugoniot curves and the temperature rise under shock compression were calculated to analyze the mechanism of the influence on SICR characteristics by additives. Impact-initiated experiments of Al/Ni composites were carried out to study SICR characters at various impact velocities. The parameters of SICR model were determined by using corresponding experimental results. The calculation results showed that for the SICR process of Al/Ni, the critical shock temperature for initiation of SICR (<i>T</i>_cr = 452 K) and the apparent activation energy (<i>E</i>_a = 90.9 kJ/mol) appeared much lower than the values of normal ignition process (<i>T</i>_ig= 990 K, <i>E</i>_iga = 351.6 kJ/mol). The additive of Cu decreased the shock temperature significantly in Al/Ni composites, which led to the increase of critical shock conditions for initiation of SICR and the decrease of reaction efficiency at the same shock pressure. On the other hand, the additive of PTFE to Al/Ni composites decreased the critical shock conditions for initiation of SICR and increased the chemical reaction efficiency by participating in the reactions

Intertwined Network of Si/C Nanocables and Carbon Nanotubes as Lithium-Ion Battery Anodes

We demonstrate a new kind of Si-based anode architectures consisting of silicon nanowire/overlapped graphene sheet core–sheath nanocables (SiNW@G) intertwined with carbon nanotubes (CNTs). In such a hybrid structure, the CNTs, mechanically binding SiNW@G nanocables together, act as a buffer matrix to accommodate the volume change of SiNW@G, and overlapped graphene sheets (that is, G sheaths) effectively prevent the direct contact of silicon with the electrolyte during cycling, both of which enable the structural integrity and interfacial stabilization of such hybrid electrodes. Furthermore, the one-dimensional nature of both components affords the creation of a three-dimensional interpenetrating network of lithium ion and electron pathways in the resultant hybrids, thereby enabling efficient transport of both electrons and lithium ions upon charging/discharging. As a result, the hybrids exhibit much-improved lithium storage performance

Data_Sheet_1_Associations of lipids and lipid-lowering drugs with risk of stroke: a Mendelian randomization study.ZIP

BackgroundStroke is a leading cause of death worldwide, but it is unclear whether circulating lipids and lipid-lowering drugs are causally associated with stroke and its subtypes.MethodsWe used two-sample Mendelian randomization (MR) to examine the effects of blood lipids and lipid-lowering drugs on stroke and its subtypes.ResultsThe inverse variance weighted Mendelian randomization (IVW-MR) revealed the low-density lipoprotein cholesterol (LDL-C) (OR, 1.46; 95% CI, 1.17–1.83; p = 0.0008) and apolipoprotein B (apoB) (OR, 1.46; 95% CI, 1.21–1.77; p = 0.0001) was positively correlated with large artery stroke (LAS). However, no causal effect was found in LDL-C and apoB on LAS risk when we conducted mvMR. The IVW-MR also found a suggestive evidence that decreased LDL-C levels mediated by the PCSK9 (proprotein convertase subtilisin-kexin type 9) gene were associated with a reduced risk of any stroke (AS) (OR, 1.31; 95% CI, 1.13–1.52; p = 0.0003), any ischemic stroke (AIS) (OR, 1.29; 95% CI, 1.10–1.51; p = 0.001), and LAS (OR, 1.73; 95% CI, 1.15–2.59; p = 0.008), while NPC1L1 (Niemann-Pick C1-like protein)-mediated LDL-C levels were associated with a higher risk of small vessel stroke (SVS) (OR, 6.10; 95% CI, 2.13–17.43; p = 0.0008). The SMR revealed that expression of PCSK9 was associated with risk of AS (OR, 1.15; 95% CI, 1.03–1.28; p = 0.01), AIS (OR, 1.02; 95% CI, 1.14–1.29; p = 0.03), cardioembolic stroke (CES) (OR, 1.28; 95% CI, 1.01–1.61; p = 0.04). And, a significant association was found between the expression of NPC1L1 and the risk of SVS (OR, 1.15; 95% CI, 1.00–1.32; p = 0.04).ConclusionWe cautiously find that LDL-C and apoB was positively correlated with LAS. These findings suggest that the reducing LDL-C levels could be an effective prevention strategy for reducing the risk of stroke.</p

High Volumetric Capacity Silicon-Based Lithium Battery Anodes by Nanoscale System Engineering

The nanostructuring of silicon (Si) has recently received great attention, as it holds potential to deal with the dramatic volume change of Si and thus improve lithium storage performance. Unfortunately, such transformative materials design principle has generally been plagued by the relatively low tap density of Si and hence mediocre volumetric capacity (and also volumetric energy density) of the battery. Here, we propose and demonstrate an electrode consisting of a textured silicon@graphitic carbon nanowire array. Such a unique electrode structure is designed based on a nanoscale system engineering strategy. The resultant electrode prototype exhibits unprecedented lithium storage performance, especially in terms of volumetric capacity, without the expense of compromising other components of the battery. The fabrication method is simple and scalable, providing new avenues for the rational engineering of Si-based electrodes simultaneously at the individual materials unit scale and the materials ensemble scale

Adaptable Silicon–Carbon Nanocables Sandwiched between Reduced Graphene Oxide Sheets as Lithium Ion Battery Anodes

Silicon has been touted as one of the most promising anode materials for next generation lithium ion batteries. Yet, how to build energetic silicon-based electrode architectures by addressing the structural and interfacial stability issues facing silicon anodes still remains a big challenge. Here, we develop a novel kind of self-supporting binder-free silicon-based anodes <i>via</i> the encapsulation of silicon nanowires (SiNWs) with dual adaptable apparels (overlapped graphene (G) sheaths and reduced graphene oxide (RGO) overcoats). In the resulted architecture (namely, SiNW@G@RGO), the overlapped graphene sheets, as adaptable but sealed sheaths, prevent the direct exposure of encapsulated silicon to the electrolyte and enable the structural and interfacial stabilization of silicon nanowires. Meanwhile, the flexible and conductive RGO overcoats accommodate the volume change of embedded SiNW@G nanocables and thus maintain the structural and electrical integrity of the SiNW@G@RGO. As a result, the SiNW@G@RGO electrodes exhibit high reversible specific capacity of 1600 mAh g^–1 at 2.1 A g^–1, 80% capacity retention after 100 cycles, and superior rate capability (500 mAh g^–1 at 8.4 A g^–1) on the basis of the total electrode weight

Perovskite Solar Cell Using a Two-Dimensional Titania Nanosheet Thin Film as the Compact Layer

The compact layer plays an important role in conducting electrons and blocking holes in perovskite solar cells (PSCs). Here, we use a two-dimensional titania nanosheet (TNS) thin film as the compact layer in CH₃NH₃PbI₃ PSCs. TNS thin films with thicknesses ranging from 8 to 75 nm were prepared by an electrophoretic deposition method from a dilute TNS/tetrabutylammonium hydroxide solution. The TNS thin films contact the fluorine-doped tin oxide grains perfectly. Our results show that a 8-nm-thick TNS film is sufficient for acting as the compact layer. Currently, the PSC with a TNS compact layer has a high efficiency of 10.7% and relatively low hysteresis behavior

Self-Assembly of One-Dimensional Nanocrystal Superlattice Chains Mediated by Molecular Clusters

Self-assembly of nanocrystal (NC) building blocks into mesoscopic superstructures with well-defined symmetry and geometry is essential for creating new materials with rationally designed properties. Despite the tremendous progress in colloidal assembly, it remains a fundamental challenge to assemble isotropic spherical NCs into one-dimensional (1D) ordered superstructures. Here, we report a new and general methodology that utilizes molecular clusters to induce the anisotropic assembly of NCs in solution, yielding polymer-like, single-NC-wide linear chains comprising as many as ∼1000 close-packed NCs. This cluster-assisted assembly process is applicable to various metallic, semiconductor, and magnetic NCs of different sizes and shapes. Mechanistic investigation reveals that the solvent-induced association of clusters plays a key role in driving the anisotropic assembly of NCs. Our work opens a solution-based route for linearly assembling NCs and represents an important step toward the bottom-up construction of 1D ordered NC superstructures

Replication and virulence in pigs of the first African swine fever virus isolated in China

African swine fever (ASF) entered China in August 2018 and rapidly spread across the entire country, severely threatening the Chinese domestic pig population, which accounts for more than 50% of the pig population worldwide. In this study, an ASFV isolate, Pig/Heilongjiang/2018 (Pig/HLJ/18), was isolated in primary porcine alveolar macrophages (PAMs) from a pig sample from an ASF outbreak farm. The isolate was characterized by using the haemadsorption (HAD) test, Western blotting and immunofluorescence, and electronic microscopy. Phylogenetic analysis of the viral p72 gene revealed that Pig/HLJ/18 belongs to Genotype II. Infectious titres of virus propagated in primary PAMs and pig marrow macrophages were as high as 107.2 HAD50/ml. Specific-pathogen-free pigs intramuscularly inoculated with different virus dosages at 103.5–106.5 HAD50 showed acute disease with fever and haemorrhagic signs. The incubation periods were 3–5 days for virus-inoculated pigs and 9 days for contact pigs. All virus-inoculated pigs died between 6–9 days post-inoculation (p.i.), and the contact pigs died between 13–14 days post-contact (p.c.). Viremia started on day 2 p.i. in inoculated pigs and on day 9 p.c. in contact pigs. Viral genomic DNA started to be detected from oral and rectal swab samples on 2–5 days p.i. in virus-inoculated pigs, and 6–10 days p.c. in contact pigs. These results indicate that Pig/HLJ/18 is highly virulent and transmissible in domestic pigs. Our study demonstrates the threat of ASFV and emphasizes the need to control and eradicate ASF in China.</p

Neutralizing antibodies elicited in the Env expressing LC16m8 Δ prime/SeV boost regimen.

<p> (A) ID₅₀ of individual mouse serum against SF162 envelope-pseudotyped virus was determined using TZM-bl cells. Groups I, G and J consisted of 21, 17 and 14 mice, respectively. (B) Antibodies from randomly selected mice sera from group G, I, J and control were purified using protein A Sepharose. ID₅₀ of individual mouse serum against SF162 envelope-pseudotyped virus vs 50% inhibitory concentration (IC₅₀) (concentration of purified IgG that caused a 50% reduction in the RLU compared to virus control) of individual purified IgG was plotted. The regression line and R square are shown.</p