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Vertebrates diverged from other chordates ~500 Myr ago and experienced successful innovations and adaptations, but the genomic basis underlying vertebrate origins are not fully understood. Here we suggest, through comparison with multiple lancelet (amphioxus) genomes, that ancient vertebrates experienced high rates of protein evolution, genome rearrangement and domain shuffling and that these rates greatly slowed down after the divergence of jawed and jawless vertebrates. Compared with lancelets, modern vertebrates retain, at least relatively, less protein diversity, fewer nucleotide polymorphisms, domain combinations and conserved non-coding elements (CNE). Modern vertebrates also lost substantial transposable element (TE) diversity, whereas lancelets preserve high TE diversity that includes even the long-sought RAG transposon. Lancelets also exhibit rapid gene turnover, pervasive transcription, fastest exon shuffling in metazoans and substantial TE methylation not observed in other invertebrates. These new lancelet genome sequences provide new insights into the chordate ancestral state and the vertebrate evolution.

Lithium bis͑fluorosulfonyl͒imide ͑LiFSI͒ has been investigated as a conducting salt of liquid electrolytes for lithium-ion batteries. It shows high solubility in most polar solvents, and a concentration of 5 M ͑mol dm −3 ͒ is reached in dimethyl carbonate ͑DMC͒ despite its low dielectric constant. LiFSI shows a thermal stability up to 180°C on the thermogravimetric test. Compared with the LiPF 6 /carbonate electrolytes, the LiFSI-based ones show higher ionic conductivities over a wide temperature range ͑−50 to 50°C͒ and higher lithium-ion transference numbers ͑t Li +͒ of 0.5-0.6. The conductivities of the LiFSI/DMC electrolyte over the 0.1-5 M concentration range obey a modified Casteel-Amis equation. The temperature dependence of 1 M LiFSI/DMC/EMC ͑3:7, v/v͒ is governed by the Vogel-Tammann-Fulcher relationship. The Fourier transform infrared spectra of the LiFSI/DMC electrolytes at different concentrations are systematically investigated. DMC shows significant spectral variations upon adding LiFSI, indicating strong interaction of Li + cations with the solvent molecules. We also found that the compatibility with graphite anode and LiFePO 4 cathode in the LiFSI-based electrolyte is as good as that in the LiPF 6 -based one, though aluminum ͑Al͒ corrosion occurs above 4 V vs Li + /Li. LiFSI is a very good contender to replace the latter, with increased performances and safety.

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endowed exosomes with different biological functions such as immune response and intercellular communication. [2-4] Molecular profiling of tumor-associated exosomes especially surface proteins and miRNAs has been used in cancer diagnosis and monitoring of treatment response. [5,6] For example, exosomal surface proteins such as CD24, epithelial cell adhesion molecule (EpCAM), epidermal growth factor receptor (EGFR), and ephrin type-A receptor 2 (EphA2) can be used for cancer diagnosis, exosome enrichment, and as normalization indicators for exosome concentrations. [7-10] Also, owing to the high stability of miRNAs in exosomes, exosomal miRNAs have been used as new biomarkers of various cancers, such as lung, [11] pancreatic, [12] breast, and prostate cancers. [13,14] Thus, surface proteins and miRNAs of exosomes could provide much information on disease progression. Currently, significant progress has been made toward exosome separation and detection with improved sensitivity, multiplicity, and speed. Among these, integrated microfluidic chips are one of the most practical solutions, owing to their ability to simultaneously separate and detect exosomal biomarkers. To date, two kinds of microfluidic platforms, immunoaffinitybased and size-based exosome isolation, have been reported. Immunoaffinity-based exosome isolation was performed by manipulating affinity particles/magnetic bead, [15-17] or modifying microchannel surface with antibodies (Abs). [18,19] Microfluidic Exosomes are recognized as promising biomarkers for early cancer diagnosis and prognosis owing to a large amount of biological information they carried. But the key is that single type of exosomal biomarker analysis is not sufficient enough for accurate cancer diagnosis and stage monitoring due to the insufficient information and high false positive signal. To address the challenge, here simultaneous in situ detection of different types of exosomal biomarkers (surface proteins: CD81, ephrin type-A receptor 2, and carbohydrate antigen 19-9; miRNAs: miR-451a, miR-21, and miR-10b) is conducted with a 3D microfluidic chip, which works in conjunction with quantum dot (QD) labeling and vesicle fusion technology. After exosomes are efficiently captured by the microfluidic chip, the quantification of multiple exosomal proteins is achieved by using three kinds of QDs with the same excitation and different emission wavelengths, and virus-mimicking fusogenic vesicles encapsulating three exquisitely engineered molecular beacons are introduced for ultrasensitive detection of multiple exosomal miRNAs without requiring RNA extraction. Through comprehensive profiling different types of exosomal biomarkers, the false positive rate is substantially avoided and the accuracy of cancer diagnosis and stage monitoring is improved to ≈100%, which are critical to cancer effective treatment and favorable prognosis.

The electrochemical insertion of Li into graphite initiates a series of thermodynamic and kinetic processes. An in-depth understanding of this phenomenon will deepen the knowledge of electrode material design and optimize rechargeable Li batteries. In this context, the phase transition from dense stage II (LiC) to stage I (LiC) was comprehensively elucidated in a graphite anode via both experimental characterizations and first-principles calculations. The results indicate that, although the transition from stage II to stage I is thermodynamically allowed, the process is kinetically prohibited because Li ions tend to cluster into stage compounds rather than form a solid solution. Additionally, the phase transitions involve at least three intermediate structures (1T, 2H, and 3R) before reaching the LiC (stage I) phase. These findings provide new insights into the electrochemical behavior of graphite and the electrode process kinetics for rechargeable Li batteries.

Extracellular vesicles (EVs) have the potential to be utilized as disease-specific biomarkers. Although strategies for on-chip isolation and detection of EVs have recently been developed, they need preprocessing of clinical samples and are not accurate enough for disease diagnosis just judging by EVs concentration. Here, we designed an integrated microfluidic device named a plasma separation and EV detection (PS-ED) chip for plasma separation, quantification, and high-throughput protein analysis of EVs directly from clinical whole blood samples. The device included two modules (PS and ED module): the PS module was a six-loop microchannel for rapid separation of plasma from clinical whole blood samples under inertial force; the amount of EVs in the separated plasma kept the same value as in the initial blood samples. The module reduced the mechanical damage to the blood cells and thus reduced the interference of debris or cellular contents from damaged cells during EVs detection; the ED module contained four S-channels for quantification and high-throughput protein analysis of EVs; a wide detection range from 2.5 × 102 to 2.5 × 108 particles/μL with a detection limit of 95 particles/μL was obtained. Through simultanously monitoring three proteins (CD81, CD24, and EpCAM) of EVs, the cancer type can be accurately confirmed. Furthermore, clinical blood sample analysis verified that the proposed device could be used for accurate diagnosis and therapy monitoring of ovarian cancer.

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