Printed electronics is a revolutionary technology aimed at unconventional electronic device manufacture on plastic foils, and will probably rely on polymeric semiconductors for organic thin-film transistor (OTFT) fabrication. In addition to having excellent charge-transport characteristics in ambient conditions, such materials must meet other key requirements, such as chemical stability, large solubility in common solvents, and inexpensive solution and/or low-temperature processing. Furthermore, compatibility of both p-channel (hole-transporting) and n-channel (electron-transporting) semiconductors with a single combination of gate dielectric and contact materials is highly desirable to enable powerful complementary circuit technologies, where p- and n-channel OTFTs operate in concert. Polymeric complementary circuits operating in ambient conditions are currently difficult to realize: although excellent p-channel polymers are widely available, the achievement of high-performance n-channel polymers is more challenging. Here we report a highly soluble ( approximately 60 g l(-1)) and printable n-channel polymer exhibiting unprecedented OTFT characteristics (electron mobilities up to approximately 0.45-0.85 cm(2) V(-1) s(-1)) under ambient conditions in combination with Au contacts and various polymeric dielectrics. Several top-gate OTFTs on plastic substrates were fabricated with the semiconductor-dielectric layers deposited by spin-coating as well as by gravure, flexographic and inkjet printing, demonstrating great processing versatility. Finally, all-printed polymeric complementary inverters (with gain 25-65) have been demonstrated.

Dysbiosis, departure of the gut microbiome from a healthy state, has been suggested to be a powerful biomarker of disease incidence and progression. Diagnostic applications have been proposed for inflammatory bowel disease diagnosis and prognosis, colorectal cancer prescreening and therapeutic choices in melanoma. Noninvasive sampling could facilitate large-scale public health applications, including early diagnosis and risk assessment in metabolic and cardiovascular diseases. To understand the generalizability of microbiota-based diagnostic models of metabolic disease, we characterized the gut microbiota of 7,009 individuals from 14 districts within 1 province in China. Among phenotypes, host location showed the strongest associations with microbiota variations. Microbiota-based metabolic disease models developed in one location failed when used elsewhere, suggesting that such models cannot be extrapolated. Interpolated models performed much better, especially in diseases with obvious microbiota-related characteristics. Interpolation efficiency decreased as geographic scale increased, indicating a need to build localized baseline and disease models to predict metabolic risks.

Two new n-channel polymeric semiconductors for organic thin-film transistors (TFTs) based on electron-depleted perylene- (PDI) and naphthalene-dicarboxyimide (NDI) polymerized with dithiophene are reported: poly{[N,N'-bis(2-octyldodecyl)-1,4,5,8-naphthalene dicarboximide-2,6-diyl]-alt-5,5'-(2,2'-bithiophene)}, P(NDI2OD-T2), and poly{[N,N'-bis(2-octyldodecyl)-3,4,9,10-perylenedicarboximide-(1,7&1,6)-diyl]-alt-5,5'-(2,2'-bithiophene)}, P(PDI2OD-T2). Polymer regioregularity and electronic structure strongly depend on the rylene co-monomer. The use of NDI enables a regioregular and high-molecular-weight polymer with greatly stabilized electron transport in ambient. Unoptimized P(NDI2OD-T2)-based TFTs exhibit good electron mobilities [mu(e) approximately 0.04 (0.01) cm(2)/V.s in vacuum (ambient after 16 weeks) vs mu(e) approximately 0.003 (2 x 10(-4)) cm(2)/V.s in vacuum (ambient after 1.5 week) for P(PDI2OD-T2)] and on-off current modulation [I(on):I(off) > 10(6)].

BackgroundGut microbiota has been suggested to play a role in almost all major diseases including cardio‐ and cerebrovascular diseases. A possible mechanism is the transformation of dietary choline and l‐carnitine into trimethylamine by gut bacteria. This metabolite is further oxidized into trimethylamine‐N‐oxide (TMAO) in liver and promotes atherogenesis. Nevertheless, little is known about gut microbial diversity and blood TMAO levels in stroke patients.Methods and ResultsWe performed a case‐control study of patients with large‐artery atherosclerotic ischemic stroke and transient ischemic attack. TMAO was determined with liquid chromatography tandem mass spectrometry. Gut microbiome was profiled using Illumina sequencing of the 16S rRNA V4 tag. Within the asymptomatic control group, participants with and without carotid atherosclerotic plaques showed similar levels of TMAO without a significant difference in gut microbiota; however, the gut microbiome of stroke and transient ischemic attack patients was clearly different from that of the asymptomatic group. Stroke and transient ischemic attack patients had more opportunistic pathogens, such as Enterobacter, Megasphaera, Oscillibacter, and Desulfovibrio, and fewer commensal or beneficial genera including Bacteroides, Prevotella, and Faecalibacterium. This dysbiosis was correlated with the severity of the disease. The TMAO level in the stroke and transient ischemic attack patients was significantly lower, rather than higher, than that of the asymptomatic group.ConclusionsParticipants with asymptomatic atherosclerosis did not exhibit an obvious change in gut microbiota and blood TMAO levels; however, stroke and transient ischemic attack patients showed significant dysbiosis of the gut microbiota, and their blood TMAO levels were decreased.