Sensitive and Fast Humidity Sensor Based on A Redox Conducting Supramolecular Ionic Material for Respiration Monitoring

Real-time monitoring of respiratory rate (RR) is highly important for human health, clinical diagnosis, and fundamental scientific research. Exhaled humidity-based RR monitoring has recently attracted increased attention because of its accuracy and portability. Here, we report a new design of an exhaled humidity sensor for the real-time monitoring of the RR based on a synthetic redox conducting supramolecular ionic material (SIM). The humidity-dependent conducting SIM is prepared by ionic self-assembly in aqueous solutions of electroactive 2,2′-azino-bis­(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 1,10-bis­(3-methylimidazolium-1-yl) decane (C₁₀(mim)₂). By taking full advantage of the high hygroscopicity and water stability arising from the ionic and hydrophobic interactions between two building blocks (i.e., ABTS and C₁₀(mim)₂), the SIM-based humidity sensor exhibits both high sensitivity (less than 0.1% relative humidity) and fast response time (∼37 ms). These excellent properties allow this humidity sensor to noninvasively monitor the RRs of not only humans but also rats that have a much faster RR and much smaller tidal volume than humans. Moreover, this sensor could also be efficiently used for the real-time monitoring of the recovery process of rats from anesthesia

Organocatalytic Asymmetric Synthesis of Chiral Dioxazinanes and Dioxazepanes with <i>in Situ</i> Generated Nitrones via a Tandem Reaction Pathway Using a Cooperative Cation Binding Catalyst

Heterocyclic skeletons play major roles in pharmaceuticals and biological processes. Cycloaddition reactions are most suitable synthetic tools to efficiently construct chemically diverse sets of heterocycles with great structural complexity owing to the simultaneous or sequential formation of two or more bonds, often with a high degree of selectivity. Herein, we report an unprecedented formal cycloaddition of <i>N</i>-Boc-<i>N</i>-hydroxy amido sulfones as the nitrone precursors with terminal-hydroxy α,β-unsaturated carbonyls in the presence of Song’s chiral oligoethylene glycol as a cation-binding catalyst and KF as a base to afford a wide range of highly enantio- and diastereo-enriched six-membered dioxazinane and seven-membered dioxazepane heterocycles. In this process, nitrones as well as terminal-hydroxy α,β-unsaturated carbonyls serve as “amphiphilic” building units, and the reaction proceeds through a tandem pathway sequence of oxa-Mannich reaction/oxa-Michael reaction/tautomerization/protonation. The cation-binding catalysis in a densely confined chiral space <i>in situ</i> formed by the incorporation of potassium salt is the key to this successful catalysis. This strategy opens a new pathway for the asymmetric synthesis of diverse heterocyclic skeletons of great complexity

Rumen Bacterial Diversity of 80 to 110-Day-Old Goats Using 16S rRNA Sequencing

<div><p>The ability of rumen microorganisms to use fibrous plant matter plays an important role in ruminant animals; however, little information about rumen colonization by microbial populations after weaning has been reported. In this study, high-throughput sequencing was used to investigate the establishment of this microbial population in 80 to 110-day-old goats. Illumina sequencing of goat rumen samples yielded 101,356,610 nucleotides that were assembled into 256,868 reads with an average read length of 394 nucleotides. Taxonomic analysis of metagenomic reads indicated that the predominant phyla were distinct at different growth stages. The phyla Firmicutes and Synergistetes were predominant in samples taken from 80 to 100-day-old goats, but Bacteroidetes and Firmicutes became the most abundant phyla in samples from 110-day-old animals. There was a remarkable variation in the microbial populations with age; Firmicutes and Synergistetes decreased after weaning, but Bacteroidetes and Proteobacteria increased from 80 to 110 day of age. These findings suggested that colonization of the rumen by microorganisms is related to their function in the rumen digestive system. These results give a better understanding of the role of rumen microbes and the establishment of the microbial population, which help to maintain the host’s health and improve animal performance.</p></div

Rarefaction analysis of the different samples.

<p>Rarefaction curves of OTUs clustered at 97% sequence identity across different samples.</p

The relative abundance (%) of cellulose-degrading bacteria in different age groups of goats.

<p>The relative abundance (%) of cellulose-degrading bacteria in different age groups of goats.</p

Diversity estimation of the 16S rRNA gene libraries of the rumen of goats from the sequencing analysis^a.

<p>^a The operational taxonomic units (OTUs) were defined with 3% dissimilarity. The richness estimators (ACE and Chao) and diversity indices (Shannon and Simpson) were calculated.</p><p>^b The 80-day-old group samples included goats 21, 22 and 23; the 90-day-old group samples included goats 31, 32 and 33; the 100-day-old group samples included goats 41, 42 and 43; the 110-day-old group samples included goats 51, 52 and 53.</p><p>Diversity estimation of the 16S rRNA gene libraries of the rumen of goats from the sequencing analysis<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0117811#t001fn001" target="_blank">^a</a>.</p

Genera-level composition of the rumen microbiome.

<p>A color-coded bar plot showing the average bacterial genera distribution across the different age groups that were sampled.</p

A heat map of the rumen microbiome composition at the species level.

<p>The heat map indicates the relative percentage of each genera for the different age groups sampled.</p

Temporal changes in the relative abundance (% reads) of (A) the most dominant phylum and (B) the most dominant genera in the rumen microbial community of goats with age.

<p>Error bars represent the SD of three samples. Boxes with a different letter above the error bars are significantly different at P<0.05 or P<0.1 (Firmicutes) by <i>t</i>-test analyses.</p

Asymmetric Mannich Reaction and Construction of Axially Chiral Sulfone-Containing Styrenes in One Pot from α‑Amido Sulfones Based on the Waste–Reuse Strategy

A simultaneous asymmetric Mannich reaction and the construction of axially chiral sulfone-containing styrenes in one pot from α-amido sulfones based on the waste–reuse strategy was demonstrated. A series of chiral β-amino diesters and axially chiral sulfone-containing styrenes with various functional groups were synthesized in good to excellent yields and enantioselectivities under mild conditions. In addition, this protocol has been successfully applied to synthesize the anti-HIV drug Maraviroc and chiral trichloro derivatives