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The thin film microstructure development of functionalized oligothiophenes with branched, thermally removable groups at each end of conjugated cores with five, six, and seven thiophene rings was monitored during their thermal conversion from solution processible precursors to insoluble semiconductor products. The change in end group character provides a comparison of branched vs linear end group functionalization in oligothiophenes. Near edge X-ray absorption fine structure (NEXAFS) spectroscopy confirmed that branched alpha-, omega-substitutions of the precursors strongly influenced the packing of the conjugated core. The quinque- and sexithiophene precursors oriented perpendicular to the substrate, whereas the septithiophene precursor oriented parallel to the substrate, providing one of the first examples of length dependence in oligothiophene orientation. This dependence may be due to a packing mismatch between the conjugated cores and the branched end groups. The convertible septithiophene exhibits four distinct microstructures as it converts from precursor to product that correlate strongly with its field-effect hole mobility in field-effect transistors. The extent of septithiophene order and the surface-relative orientation of its ordered phases clearly influence field-effect transistor performance.

Abstract To introduce crown ethers into the struts of metal–organic frameworks (MOFs), general approaches have been developed for the syntheses of dicarboxylic acid dibenzo[30]crown‐10 (DB30C10DA), dicarboxylic acid di‐2,3‐naphtho[30]crown‐10 (DN30C10DA), dicarboxylic acid bisparaphenylene[34]crown‐10 (BPP34C10DA), and dicarboxylic acid 1,5‐naphthoparaphenylene[36]crown‐10 (NPP36C10DA). These novel crown ethers not only retain the characteristics of their parent crown ethers since they can 1) bind cationic guests and 2) serve as templates for making mechanically interlocked molecules (MIMs), such as catenanes and rotaxanes, but they also present coordination sites to connect with secondary building units (SBUs) in MOFs. The binding behavior of BPP34C10DA with 1,1′‐dimethyl‐4,4′‐bipyridinium bis(hexafluorophosphate) (DMBP ⋅ 2 PF 6 ) has been investigated by means of UV/Vis, fluorescence, and NMR spectroscopic techniques. The crystal superstructure of the complex DMBP ⋅ 2 PF 6 ⊂ BPP34C10DA was determined by X‐ray crystallography. The NPP36C10DA‐based [2]catenane (H 2 NPP36C10DC‐CAT ⋅ 4 PF 6 ) and the BPP34C10DA‐based [2]catenane (H 2 BPP34C10DC‐CAT ⋅ 4 PF 6 ) were prepared in DMF at room temperature by the template‐directed clipping reactions of the planarly chiral NPP36C10DA and BPP34C10DA with 1,1′‐[1,4‐phenylenebis(methylene)]di‐4,4′‐bipyridin‐1‐ium bis(hexafluorophosphate) and 1,4‐bis(bromomethyl)benzene, respectively. The crystal structure of the dimethyl ester (BPP34C10DE‐CAT ⋅ 4 PF 6 ) of the [2]catenane H 2 BPP34C10DC‐CAT ⋅ 4 PF 6 was investigated by X‐ray crystallography, which revealed racemic R and S isomers with planar chirality present in the crystal in a 1:1 ratio. These crown ether based struts serve as excellent organic ligands to bind with transition metal ions in the construction of MOFs: the crown ethers BPP34C10DA and NPP36C10DA in the presence of Zn(NO 3 ) 2 ⋅ 4 H 2 O afforded the MOF‐1001 and MOF‐1002 frameworks, respectively. The crystal structures of MOF‐1001 and MOF‐1002 are both cubic and display Fm $\bar 3$ m symmetry. The unit cell parameter of the metal–organic frameworks is a =52.9345 Å. Since such MOFs, containing electron‐donating crown ethers are capable of docking incoming electron‐accepting substrates in a stereoelectronically controlled fashion, the present work opens a new access to the preparation and application of MOFs.

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Alfred Werner's work on the geometric aspects of how ligands bind to metal ions at the end of the 19th century has given rise, in the molecular realm, to organometallic, bioinorganic, and cluster chemistries. By stitching together organic and inorganic units into crystalline porous metal-organic frameworks (MOFs), the connectivity, spatial arrangement, and geometry of those molecular complexes can now be fixed in space and become directly addressable. The fact that MOFs are porous provides additional space within which molecules can further be transformed and their chemistry controlled. An aspect not available in molecular chemistry but a direct consequence of Werner's analysis of coordination complexes is the ability to have multivariable functionality in MOFs to bring about a continuum of chemical environments, within the repeating order of the framework, from which a substrate can sample and be transformed in ways not possible in molecular complex chemistry.

Abstract Fungal solid-state fermentation (SSF) of byproducts has promise for increasing food sustainability and security, but fungal waste-to-food upcycling remains poorly understood at the molecular level. Here we use a multi-omics approach to characterize oncom – a fermented food traditionally produced from byproducts in Java, Indonesia – as a model system for understanding fungal waste conversion. Metagenomic sequencing of two oncom types (red and black) indicated that Neurospora intermedia is the fungus dominating red oncom. Further transcriptomic, metabolomic, and phylogenomic analysis revealed that oncom-derived N. intermedia utilizes pectin and cellulose degradation for substrate conversion and belongs to a distinct byproduct-associated subpopulation that differs from wild strains at the genetic and biochemical level. Finally, we found that N. intermedia grew on a range of industrially relevant byproducts, did not encode for any known mycotoxins, and could be used to create foods that were positively perceived by consumers outside Indonesia. This study uncovers the microbial and genetic basis of a traditional upcycled food, sheds light on human domestication of microbes for sustainability challenges, and establishes the edible N. intermedia as a promising fungus for byproduct upcycling in SSF and beyond.

Focusing electromagnetic energy to sub-wavelength dimensions has become an increasingly active field of research for a variety of applications such as Heat Assisted Magnetic Recording (HAMR), nanolithography, and nanoscale optical characterization of biological cells and single molecules using near-field scanning optical microscopy (NSOM) technique. Double-sided surface plasmons in a metal-insulator-metal (MIM) geometry have been shown to have very small wavelengths for dielectric of thickness of less than 10 nm. A tapered dielectric structure sandwiched between metal, can be used to efficiently couple electromagnetic energy from free space photons to the plasmonic wavelengths at the nanoscale. In this paper, we present the fabrication and characterization of a novel MIM plasmonic lens structure.

Catastrophizing about sleeplessness is a cognitive process associated with sleep disturbance in adults. This study aimed to (1) examine whether children catastrophize about the consequences of not sleeping; (2) define the topics that children catastrophize about; (3) assess whether there is a link between catastrophizing and sleep disturbance in children; and (4) examine whether an association between catastrophizing and sleep in children is mediated by anxiety and depression symptoms. Children completed the sleep self-report and a catastrophizing interview. Testing took place in two inner-city schools in London, UK and participants comprised 123 children aged between 8 and 10 years (49% male). Thirty-four (28%) participants reported concerns in response to the catastrophizing questionnaire. The main topics being catastrophized were concerns about sleep, physiological issues and one's own emotions. Catastrophes predicted sleep disturbance after controlling for age and sex (beta = 0.35, P < 0.001) but not when controlling additionally for anxiety and depression symptoms (beta = 0.15, P = 0.106). Symptoms of anxiety (Sobel test = 3.30, P < 0.001) and depression (Sobel test = 2.90, P = 0.004) mediated the influence of catastrophizing on sleep. A proportion of children catastrophized about the consequences of sleeplessness and this was associated with sleep disturbance, an association which was mediated through anxiety and depression symptoms.

We describe a general approach for identifying components of subcellular structures in a multicellular organism by exploiting the ability to generate thousands of independent transformants in Arabidopsis thaliana . A library of Arabidopsis cDNAs was constructed so that the cDNAs were inserted at the 3′ end of the green fluorescent protein (GFP) coding sequence. The library was introduced en masse into Arabidopsis by Agrobacterium -mediated transformation. Fluorescence imaging of 5,700 transgenic plants indicated that ≈2% of lines expressed a fusion protein with a different subcellular distribution than that of soluble GFP. About half of the markers identified were targeted to peroxisomes or other subcellular destinations by non-native coding sequence (i.e., out-of-frame cDNAs). This observation suggests that some targeting signals are of sufficiently low information content that they can be generated frequently by chance. The potential of the approach for identifying markers with unique dynamic processes is demonstrated by the identification of a GFP fusion protein that displays a cell-cycle regulated change in subcellular distribution. Our results indicate that screening GFP-fusion protein libraries is a useful approach for identifying and visualizing components of subcellular structures and their associated dynamics in higher plant cells.

The synthesis of bimetallic molecular silicide complexes is reported, based on the use of multiple Si-H bond activations in SiH₄ at the metal centers of 14-electron LCo^I fragments (L = Tp″, HB(3,5-diisopropylpyrazolyl)₃^-; [BP₂^<i>t</i>BuPz], PhB(CH₂P^<i>t</i>Bu₂)₂(pyrazolyl)). Upon exposure of (Tp″Co)₂(μ-N₂) (<b>1</b>) to SiH₄, a mixture of (Tp″Co)₂(μ-H) (<b>2</b>) and (Tp″Co)₂(μ-H)₂ (<b>3</b>) was formed and no evidence for Si-H oxidative addition products was observed. In contrast, [BP₂^<i>t</i>BuPz]-supported Co complexes led to Si-H oxidative additions with the generation of silylene and silicide complexes as products. Notably, the reaction of ([BP₂^<i>t</i>BuPz]Co)₂(μ-N₂) (<b>5</b>) with SiH₄ gave the dicobalt silicide complex [BP₂^<i>t</i>BuPz](H)₂Co═Si═Co(H)₂[BP₂^<i>t</i>BuPz] (<b>8</b>) in high yield, representing the first direct route to a symmetrical bimetallic silicide. The effect of the [BP₂^<i>t</i>BuPz] ligand on Co-Si bonding in <b>7</b> and <b>8</b> was explored by analysis of solid-state molecular structures and density functional theory (DFT) investigations. Upon exposure to CO or DMAP (DMAP = 4-dimethylaminopyridine), <b>8</b> converted to the corresponding [BP₂^<i>t</i>BuPz]Co(L)_x adducts (L = CO, <i>x</i> = 2; L = DMAP, <i>x</i> = 1) with concomitant loss of SiH₄, despite the lack of significant Si-H interactions in the starting complex. On heating to 60 °C, <b>8</b> underwent reaction with MeCl to produce small quantities of Me_<i>x</i>SiH_4-<i>x</i> (<i>x</i> = 1-3), demonstrating functionalization of the μ-silicon atom in a molecular silicide to form organosilanes.