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Near‐infrared organic light‐emitting diodes (NIR OLEDs) with emission peak above 900 nm are attractive for many emerging applications, spanning from bioimaging to light detection and ranging. However, the device performance of NIR OLEDs is generally limited by the low quantum efficiency of emitters because of the fast nonradiative transition process imposed by energy‐gap law and aggregation quenching. So far, only a few Pt(II) complexes delivering external quantum efficiency (EQE) over 1% are reported, while there is no comparable electroluminescence in heavy‐metal‐free fluorescent organic emitters. Here, NIR OLEDs centered at 934 nm by blending an acceptor–donor–acceptor type molecule Y11 into a polymer host poly[(9,9‐dioctylfluorenyl‐2,7‐diyl)‐alt‐(4,4′‐(N‐(4‐sec‐butylphenyl)diphenylamine) (TFB) are reported. The OLEDs show a remarkably high EQE of 1.72%. Moreover, owing to a low turn‐on voltage (≈0.9 V), the resultant NIR OLEDs have an electricity‐to‐light power efficiency surpassing 20 mW W−1. The improved device performance can be attributed to enhanced photoluminescence quantum yields (PLQYs) of the blends owing to suppressed aggregation quenching, and favorable light extraction from the emissive layer. Such values are the highest among fluorescent OLEDs with electroluminescence above 900 nm. [ABSTRACT FROM AUTHOR]

Bacterial infections represent one of the serious human healthcare threats, and ≈80% of bacterial infections are related to biofilm. So far, there are extensive investigations on the development of robust biomaterials toward the elimination of biofilms and synergistic antibacterial applications. Despite the progress made, concerns have always been raised regarding the sophisticated synthesis and pre‐modification of hybrid materials, complicated purification and high‐cost work. In this study, a series of robust and integrative nanoparticles (NPs) assembled from two types of natural building blocks (natural polyphenols and tobramycin antibiotics) is successfully fabricated via a one‐pot integration approach, which can efficiently destruct the biofilm structure and kill bacteria via enhanced antibiotic infiltration. Notably, natural polyphenols and tobramycin can release from the formed NPs in an on‐demand manner in the bacterial‐induced environment. The former ones can inhibit quorum sensing within bacteria through competitive combination with autoinducer‐2 (AI‐2) to remove the existing biofilm, and the latter antibiotics exert high antibacterial activity both in vitro and in vivo. This study provides new inspirations toward robust and synergistic antimicrobial and antibiofilm nanomaterials via the facile integration of naturally occurring molecules. [ABSTRACT FROM AUTHOR]

We describe the enantioselective oxidative cross‐coupling of secondary amines with ketones by combining the non‐natural catalytic activity of lipase with electrosynthesis. Various 2,2‐disubstituted 3‐carbonyl indoles with a stereogenic quaternary carbon center were synthesized from 2‐substituted indoles in yields up to 78 % with good enantio‐ and diastereoselectivities (up to 96 : 4 e.r. and >20 : 1 d.r.). This unprecedented protocol demonstrated that hydrolase catalysis is compatible with electrosynthesis, and the reaction can be carried out in organic solvents with a broad substrate scope and good stereoselectivity. This work provides insights into enzymatic electrosynthesis. [ABSTRACT FROM AUTHOR]

Summary: Red blood cells (RBCs) lose plasma membrane in the spleen as they age, but the cells and molecules involved are yet to be identified. Sickle cell disease and infection by Plasmodium falciparum cause oxidative stress that induces aggregates of cross‐linked proteins with N‐linked high‐mannose glycans (HMGs). These glycans can be recognised by mannose‐binding lectins, including the mannose receptor (CD206), expressed on macrophages and specialised phagocytic endothelial cells in the spleen to mediate the extravascular haemolysis characteristic of these diseases. We postulated this system might also mediate removal of molecules and membrane in healthy individuals. Surface expression of HMGs on RBCs from patients who had previously undergone splenectomy was therefore assessed: high levels were indeed observable as large membrane aggregates. Glycomic analysis by mass spectrometry identified a mixture of Man5‐9GlcNAc2 structures. HMG levels correlated well with manual pit counts (r = 0.75–0.85). To assess further whether HMGs might act as a splenic reticuloendothelial function test, we measured levels on RBCs from patients with potential functional hyposplenism, some of whom exhibited high levels that may indicate risk of complications. [ABSTRACT FROM AUTHOR]

Organic semiconductor devices with low energy consumption and excellent stability are highly desirable. Controlling the intermolecular alignment orientation by designing the molecular structure or optimization of the film preparation process is an alternative way to achieve this goal. In this paper, a new idea was proposed to realize the formation of an aligned monomolecular layer and multimolecular layer thin films on the electrode substrate by controlling the surface pressure of molecular layer on the liquid surface by LB technology. An amphiphilic π‐conjugated D−A molecule was synthesized, and the influence of spin coating and LB technology on intermolecular ordered stacking in the film and the electrical memory performance were investigated. The results demonstrated that the film fabricated by LB technology has some advantages compared with that fabricated by spin‐coating method, such as higher crystallinity, lower surface roughness and better‐organized monomolecular and multimolecular layer, which significantly promoted the performance of the electrical memory device with lower power consumption and longer stability. [ABSTRACT FROM AUTHOR]

The use of an amino‐functionalized β‐diketiminate (′N‐nacnac′) ligand in low‐valent silicon chemistry is investigated. In particular, the use of (LDipp)SiCl (LDipp=HC{(Me2N)CNDipp}2) to generate silicon‐containing products via metathesis chemistry is explored, in light of previously reported complications arising from heterocycle ring contraction. In the case of Na[C5H5], chloride metathesis is accompanied not by rearrangement of the N‐nacnac ligand, but by a C‐to‐Si hydrogen migration process, generating the hydridosilicon(IV) species (LDipp)Si(H)(C5H4), which features a silafulvene core. The potential intermediate arising from initial chloride/cyclopentadienide substitution can be modelled by the chemistry of the corresponding Ge(II) and Sn(II) systems, which generate (LDipp)E(η1−C5H5) (E=Ge, Sn) via straightforward metathesis chemistry. A Si(II) hydride species can be generated from (LDipp)SiCl via metathesis by making use of a d‐block reagent which can act as both hydride source and coordinative trap for (LDipp)SiH. Thus, the reaction of (LDipp)SiCl with K[(η5−C5H4Me)Mn(CO)2H] leads to the formation of (η5−C5H4Me)Mn(CO)2{Si(H)LDipp} – the first silylene complex containing this half‐sandwich manganese fragment. [ABSTRACT FROM AUTHOR]

Non‐immune cells are increasingly recognized as important in regulating immunity, but the role of red blood cells (RBC) remains relatively unexplored, despite their abundance in the circulation and a cell surface rich in potential ligands. Here, we determine whether RBC influence the activation state of human B cells. Separation of RBC from peripheral blood mononuclear cells increased B‐cell expression of HLA‐DR/DP/DQ, whilst reconstitution reduced the levels of B‐cell activation markers HLA‐DR/DP/DQ, CD86, CD69 and CD40, as well as decreasing proliferative responses and IgM secretion. Inhibition of B cells required contact with RBC and was abrogated by either removal of sialic acids from RBC or blocking the corresponding lectin receptor CD22 on B cells. Chronic lymphocytic leukaemia B cells express low levels of CD22 and were less susceptible to inhibition by RBC, which may contribute to their activated phenotype. Taken together, the results identify a novel mechanism that may suppress inappropriate responsiveness of healthy B cells whilst circulating in the bloodstream. [ABSTRACT FROM AUTHOR]

Summary: Sialic acid‐binding immunoglobulin‐like lectin (Siglec)‐15 has recently been identified as a critical tumour checkpoint, augmenting the expression and function of programmed death‐ligand 1. We raised a monoclonal antibody, A9E8, specific for Siglec‐15 using phage display. A9E8 stained myeloid leukaemia cell lines and peripheral cluster of differentiation (CD)33+ blasts and CD34+ leukaemia stem cells from patients with acute myeloid leukaemia (AML). By contrast, there was minimal expression on healthy donor leucocytes or CD34+ stem cells from non‐AML donors, suggesting targeting Siglec‐15 may have significant therapeutic advantages over its fellow Siglec CD33. After binding, A9E8 was rapidly internalised (half‐life of 180 s) into K562 cells. Antibodies to Siglec‐15 therefore hold therapeutic potential for AML treatment. [ABSTRACT FROM AUTHOR]

In this study, we determined whether multilineage‐differentiating stress‐enduring (Muse) cells exist in rat bone marrow and elucidated their effects on protection against the injury of intestinal epithelial cells associated with inflammation. Rat Muse cells were separated from bone marrow mesenchymal stem cells (BMMSCs) by trypsin‐incubation stress. The group of cells maintained the characteristics of BMMSCs; however, there were high positive expression levels of stage‐specific embryonic antigen‐3 (SSEA‐3; 75.6 ± 2.8%) and stage‐specific embryonic antigen‐1 (SSEA‐1; 74.8 ± 3.1%), as well as specific antigens including Nanog, POU class 5 homeobox 1 (OCT 3/4), and SRY‐box 2 (SOX 2). After inducing differentiation, α‐fetoprotein (endodermal), α‐smooth muscle actin and neurofilament medium polypeptide (ectodermal) were positive in Muse cells. Injuries of intestinal epithelial crypt cell‐6 (IEC‐6) and colorectal adenocarcinoma 2 (Caco‐2) cells as models were induced by tumor necrosis factor‐α stimulation in vitro. Muse cells exhibited significant protective effects on the proliferation and intestinal barrier structure, the underlying mechanisms of which were related to reduced levels of interleukin‐6 (IL‐6) and interferon‐γ (IFN‐γ), and the restoration of transforming growth factor‐β (TGF‐β) and IL‐10 in the inflammation microenvironment. In summary, there were minimal levels of pluripotent stem cells in rat bone marrow, which exhibit similar properties to human Muse cells. Rat Muse cells could provide protection against damage to intestinal epithelial cells depending on their anti‐inflammatory and immune regulatory functionality. Their functional impact was more obvious than that of BMMSCs. [ABSTRACT FROM AUTHOR]

The damage of vascular endothelial cells induced by oxidative stress plays an important role in the pathogenesis of atherosclerosis. Dihydromyricetin (DMY) is considered as a natural antioxidant. However, the mechanism of DMY on endothelial cell injury induced by oxidative stress remains unclear. In this study, we found that DMY could reduce the oxidative damage of HUVECs induced by sodium nitroprusside (SNP), HUVECs pre‐treated with DMY suppressed SNP‐induced apoptosis by reduced ROS overproduction of intracellular, decreased MDA level and elevated the superoxide dismutase activity. Meanwhile, we found that DMY could promote the expression of phosphorylated FoxO3a and Akt, and affect the nuclear localization of FoxO3a, when treated with the PI3K inhibitor LY294002, the effect of DMY was blocked. These data suggest that DMY protects HUVECs from oxidative stress by activating PI3K/Akt/FoxO3a signalling pathway. Therefore, DMY may have great therapeutic potential as a new drug for atherosclerosis. [ABSTRACT FROM AUTHOR]

Introduced here is a new type of strongly donating N‐heterocyclic boryloxy (NHBO) ligand, [(HCDippN)2BO]− (Dipp=2,6‐diisopropylphenyl), which is isoelectronic with the well‐known N‐heterocyclic iminato (NHI) donor class. This 1,3,2‐diazaborole functionalized oxy ligand has been used to stabilize the first acyclic two‐coordinate dioxysilylene and its Ge, Sn, and Pb congeners, thereby presenting the first complete series of heavier group 14 dioxycarbene analogues. All four compounds have been characterized by X‐ray crystallography and density‐functional theory, enabling analysis of periodic trends: the potential for the [(HCDippN)2BO]− ligand to subtly vary its electronic‐donor capabilities is revealed by snapshots showing the gradual evolution of arene π coordination on going from Si to Pb. New O‐donor ligand: By exploiting the isoelectronic relationship with N‐heterocyclic imines (NHIs), a new class of N‐heterocyclic boryloxy (NHBO) ligand, which is a strong O‐donor, is introduced. The NHBO ligand is used to generate the first acyclic two‐coordinate dioxysilylene and its heavier (Ge, Sn, Pb) congeners, which represent the first complete series of heavier group 14 dioxycarbene analogues. [ABSTRACT FROM AUTHOR]

Reactions of a boryl‐substituted acyclic silylene with carbon dioxide and monoxide are reported. The former proceeds through oxygen atom abstraction, generating CO (with rearrangement of the putative silanone product through silyl‐group transfer). The latter is characterized by reductive coupling of CO to give an ethynediolate fragment, which undergoes formal insertion into the Si−B bond. The net conversion of carbon dioxide with two equivalents of silylene offers a route for the three‐electron reduction of CO2 to [C2O2]2−. C−C Coupling: Reactions of a boryl‐substituted acyclic silylene with CO2 and CO are reported. The former proceeds through O‐atom abstraction (generating CO), the latter via reductive coupling of CO to give [OCCO]2−, which undergoes formal insertion into the Si−B bond. The net reaction of CO2 with two equivalents of silylene can therefore be shown to constitute a three‐electron reduction of CO2 to [C2O2]2−. [ABSTRACT FROM AUTHOR]

The use of an amino‐functionalized β‐diketiminate ("N‐nacnac") ligand in low‐valent germanium chemistry is reported, with a view to comparison with "conventional" nacnac systems. Transmetallation of the N‐nacnac ligand from lithium allows access to a versatile chlorogermylene system, and subsequent substituent exchange processes are used to generate related hydrido‐, and phosphaketenyl‐germylenes. The latter undergoes photolytically‐induced cleavage of the P–CO bond to yield an unusual imine‐coordinated N,P‐heterocyclic germylene. On the basis of DFT calculations this transformation is proposed to occur via concerted attack by the electron‐rich carbon–carbon bond of the N‐nacnac backbone accompanying CO loss, rather than via the generation of a free phosphinidene. [ABSTRACT FROM AUTHOR]

An oxidation/substitution strategy for the synthesis of silicon analogues of classical organic carbonyl compounds is reported, by making use of a novel β‐diketiminate‐supported sila‐acyl chloride—the first example of such a compound isolated without the use of a stabilizing Lewis acid. Nucleophilic substitution at the SiIV center allows direct access to the corresponding sila‐aldehyde and sila‐ester. An alternative approach utilizing the reverse order of synthetic steps is thwarted by the facile rearrangement of the corresponding SiII systems featuring either H or OR substituents. As such, the isolation of (N‐nacnac)Si(O)Cl represents a key step forward in enabling the synthesis of sila‐carbonyl compounds by a synthetic approach ubiquitous in organic chemistry. Nacnac. Who′s there? The first simple silicon analogue of an acyl chloride can be accessed by mild oxidation of an N‐nacnac‐stabilized chlorosilylene (N‐nacnac=amino‐functionalized β‐diketiminate). This sila‐acyl chloride undergoes facile functional‐group exchange to yield the corresponding sila‐ester and sila‐aldehyde in a manner analogous to that seen in classical carbonyl chemistry. [ABSTRACT FROM AUTHOR]

The doped organic/organic p-n heterojunctions have been applied as charge generation structure (CGS) in tandem organic light emitting diodes (TOLEDs). It is found that the field-induced charge generation takes place more efficiently at the interface between Li2CO3 n-doped bathocuproine (BCP:Li2CO3) and MoO3 p-doped 4,4′- N, N′-dicarbazole-biphenyl (CBP:MoO3) than at the interface between BCP:Li2CO3 and MoO3 p-doped 4,4-bis[ N-1-naphthyl- N-phenylamino]biphenyl (NPB:MoO3). It is because the process of electrons tunneling through the depletion zone from the highest occupied molecular orbit (HOMO) of CBP:MoO3 to the lowest unoccupied molecular orbit (LUMO) of BCP:Li2CO3 is more efficient than that from the HOMO of NPB:MoO3 to the LUMO of BCP:Li2CO3. Compared to the TOLED using the conventional CGS of 10-nm BCP:Li2CO3/20-nm NPB:MoO3, the one using the CGS of 10-nm BCP:Li2CO3/10-nm CBP:MoO3/10-nm NPB:MoO3 shows increased device performance. In addition, the interconnecting property of CGS of 10-nm BCP:Li2CO3/ x nm CBP:MoO3/20 − x nm NPB:MoO3 shows a strong dependence on the thickness of CBP:MoO3. We provide a new insight on optimizing Ohmic loss in the CGSs, useful for improving the performance of TOLEDs. [ABSTRACT FROM AUTHOR]

Background and Aims: The aims of this study were to investigate the proportion of clinical irritable bowel syndrome (IBS) at a tertiary hospital in China, to compare the Rome III and Rome IV criteria with regard to IBS diagnosis, to describe the agreement between the Rome III and Rome IV criteria, and to identify differences between Rome IV-positive and -negative IBS patients. Methods: A cross-sectional survey was performed among outpatients in the gastrointestinal (GI) department of a tertiary hospital. The patients were categorized as having IBS using Rome III and Rome IV criteria. Results: In total, 1,376 (91.7%) patients completed a GI symptom questionnaire. Among them, 352 were suspected of having IBS and 175 were diagnosed with IBS using the Rome III or Rome IV criteria. In particular, 170 (12.4%) patients were diagnosed with IBS using the Rome III criteria, and 84 (6.1%) patients were diagnosed using the Rome IV criteria. Rome IV IBS patients experienced more pain symptoms (P<0.01) and showed higher IBS severity scores. In contrast, no significant differences were noted for demographic characteristics, stool frequency, IBS subtype, disease course, operation history or GI infection history between Rome IV IBS patients and IBS patients not diagnosed with the Rome IV criteria. Conclusions: Rome IV-positive IBS patients represented approximately half of Rome III-positive IBS patients at a tertiary hospital in China. More specifically, Rome IV-positive IBS was mainly a subgroup of Rome III-positive IBS with more serious symptoms. [ABSTRACT FROM AUTHOR]

The synthesis of a class of electron-rich amino-functionalized β-diketiminato ( N-nacnac) ligands is reported, with two synthetic methodologies having been developed for systems bearing backbone NMe2 or NEt2 groups and a range of N-bound aryl substituents. In contrast to their (Nacnac)H counterparts, the structures of the protio-ligands feature the bis(imine) tautomer and a backbone CH2 group. Direct metalation with lithium, magnesium, or aluminium alkyls allows access to the respective metal complexes through deprotonation of the methylene function; in each case X-ray structures are consistent with a delocalized imino-amide ligand description. Transmetalation using lithium N-nacnac complexes is then exploited to access p- and f-block metal complexes, which allow for like-for-like benchmarking of the N-nacnac ligand family against their more familiar Nacnac counterparts. In the case of SnII, the degree of electronic perturbation effected by introduction of the backbone NR2 groups appears to be constrained by the inability of the amino group to achieve effective conjugation with the N2C3 heterocycle. More obvious divergence from established structural norms is observed for complexes of the harder YbII ion, with azaallyl/imino and even azaallyl/NMe2 coordination modes being demonstrated by X-ray crystallography. [ABSTRACT FROM AUTHOR]

A multicriteria decision-making methodology for the sustainability prioritization of industrial systems is proposed. The methodology incorporates a fuzzy Analytic Hierarchy Process method that allows the users to assess the soft criteria using linguistic terms. A fuzzy Analytic Network Process method is used to calculate the weights of each criterion, which can tackle the interdependencies and interactions among the criteria. The Preference Ranking Organization Method for Enrichment Evaluation approach is used to prioritize the sustainability sequence of the alternative systems. Moreover, a sensitivity analysis method was developed to investigate the most critical and sensitive criteria. The developed methodology was illustrated by a case study to rank the sustainability of five alternative hydrogen production technologies. The advantages of the developed methodology over the previous approaches were demonstrated by comparing the results determined by the proposed framework with those determined using the pervious approaches. [ABSTRACT FROM AUTHOR]

Hierarchical clustering of molecular data is commonly used for estimation of species diversity in all forms of life. Parameters appropriate for species-level clustering are usually derived from reference data and applied for the delineation of sequences of unknown species membership, although it is not clear how this should be carried out in a multilocus scenario., We introduce a novel means of concurrent clustering parameter optimization and delineation for multilocus data. A simulated annealing heuristic search is performed, whereby clustering thresholds are independently varied for each locus, but optimized according to the recovery of expected taxonomic species globally over loci. For each iteration of the search, one or more loci are randomly selected and a different threshold is separately proposed to cluster each, then the loci are linked to form global species units. Where the set of thresholds group the reference (species labelled) data with high taxonomic congruence, they are adopted for clustering of the subject (nonlabelled) sequences into global molecular operational taxonomic units (global MOTU). Four mined test data sets composed of both reference and subject sequences are combined with a newly sequenced three gene Apoidea data set, and subject to the proposed method., Even optimizing four loci and thousands of sequences, the approach rapidly convergences on a set of parameters with maximal optimality score, although the method masks a high degree of incongruence, and does not always converge on a single set of thresholds. For example, of the 476 Apoidea sequences, 70 global MOTU were inferred over the heuristic search, although the number of single gene MOTU were much lower for the 28S RNA locus, and a range of equally optimal clustering thresholds were observed for the CytB gene., We demonstrate the approach as a scalable species delineation solution for heterogeneous data sets composed of incompletely and inconsistently labelled data from public DNA data bases, for newly sequenced multilocus data, or both. The delineation over a heuristic search of clustering parameters facilitates the estimation of species diversity in multilocus data, giving species estimates that take into account uncertainty regarding choice of clustering thresholds. [ABSTRACT FROM AUTHOR]

Sialic-acid-binding immunoglobulin-like lectins, siglecs, are important immune receptors expressed widely in mammals. A unique feature of siglecs is their ability to bind sialylated glycans and transmit signals to immune cells. The CD33-related siglecs (CD33rSiglecs) form a major subfamily of the siglecs, containing a large, rapidly evolving group of genes that expanded in mammals through an inverse duplication event involving a primordial cluster of siglec genes over 180 million years ago. Humans express a much larger set of CD33rSiglecs than mice and rats, a feature that can be explained by a dramatic loss of CD33rSiglec genes in rodents. Most CD33rSiglecs have immune receptor tyrosine-based inhibitory motifs and signal negatively. Interestingly, novel DAP-12-coupled 'activating' CD33rSiglecs have been identified, such as siglec-14 and siglec-16, which are paired with the inhibitory receptors, siglec-5 and siglec-11, respectively. The evolution of these activating receptors may have been driven in part by pathogen exploitation of inhibitory siglecs, thereby providing the host with additional pathways by which to combat these pathogens. Inhibitory siglecs seem to play important and varied roles in the regulation of host immune responses. For example, several CD33rSiglecs have been implicated in the negative regulation of Toll-like receptor signalling during innate responses; siglec-G functions as a negative regulator of B1-cell expansion and appears to suppress inflammatory responses to host-derived 'danger-associated molecular patterns'. Recent work has also shown that engagement of neutrophil-expressed siglec-9 by certain strains of sialylated Group B streptococci can suppress killing responses, thereby providing experimental support for pathogen exploitation of host CD33rSiglecs. [ABSTRACT FROM AUTHOR]

A new class of N‐heterocyclic boryloxy (NHBO) ligand allows access to the first complete series of heavier Group 14 dioxycarbene analogues. Structural studies of the silylene, germylene, stannylene, and plumbylene compounds in the solid state reveal a gradual pivoting of the ligand framework to dial up arene–π interactions on going from Si (hard) to Pb (soft), as demonstrated by S. Aldridge and co‐workers in their Communication on page 4847. [ABSTRACT FROM AUTHOR]