Phenotypical and functional differences in the intrinsic skin aging process of individuals between Caucasians and Asians have generated considerable interest in dermatology and cosmetic industry. Most of the studies focused on the stratum corneum, and in some other studies inter‐individual differences overwhelms the racial difference. None of the studies comparatively analyzes the difference from the histopathological point of view. Here we report our harmonic generation microscopy study to analyse...
Wed Nov 20, 2019 17:30
Abstract Next-generation sequencing and other genomic technologies are transforming prenatal and reproductive screening and testing for fetal genetic disorders at an unprecedented pace. Original approaches of screening and testing for fetal genetic and genomic disorders were focused on a few more prevalent conditions that were easily diagnosable with pre-genomic era diagnostic tools. First, chromosomal microarray analysis and then next-generation sequencing brought technology capable...
Thu Nov 21, 2019 02:00
Abstract The polygyny threshold model predicts that a female chooses an already-mated male if the direct benefits of higher territorial quality compensate for the cost of mate sharing. The sexy son hypothesis (SSH) expands this framework from direct to indirect benefits assuming that polygynously-mated females give birth to sexy and subsequently polygynous sons. Although the SSH has generated much debate, empirical evidence is inconclusive. I argue that lack of support could be...
Thu Nov 21, 2019 02:00
A novel cyclic (R2SnAu)3 anion (3‐, R2Sn = 2,2,5,5‐tetrakis(trimethylsilyl)‐1‐stannacyclopentane‐1,1‐diyl) has been synthesized as a stable blue salt with K+(THF)6 through the reaction of stable dialkylsilylene 1 with R’3PAuCl (R’ = Et, Ph) followed by the reduction with KC8. Crystallographic and NMR analysis shows that the six‐membered (SnAu)3 ring of 3‐ is planar and highly symmetric with an equal distance of six Au‐Sn bonds. UV‐vis spectrum of 3‐ in hexane reveals an intense absorption maximum...
Thu Nov 21, 2019 21:43
Go with the flow: Microstructural and architectural attributes of vitrimers are powerful design elements for controlling their mechanical and rheological properties. Conformational entropy of their embodied monomer segments appears to dominate such properties for architecturally similar vitrimer networks. Abstract Control of equilibrium and non‐equilibrium thermomechanical behavior of poly(diketoenamine) vitrimers is shown by incorporating linear polymer segments varying in molecular weight...
Thu Nov 21, 2019 21:43
Black phosphorus (BP) is a desirable anode material for alkali metal ions storage owing to its high electronic/ionic conductivity and theoretical capacity. In‐depth understanding of the redox reactions between BP and the alkali metal ions is the key to reveal the potential and limitations of BP, thereby to guide the design of BP‐based composites for high‐performance alkali metal ion batteries. Here, we performed comparative studies of the electrochemical reactions of Li + , Na + , and K + with...
Thu Nov 21, 2019 18:53
Near‐infrared (NIR) light triggered amplified photodynamic therapy (PDT) is highly desirable for tumor treatment. Herein, we report the design and synthesis of a mitochondria‐specific, 808 nm NIR light‐activated PDT system based on the combination of metal‐organic frameworks (MOFs) and upconversion photochemistry with organelle‐targeted strategy. The system was synthesized through growth of porphyrinic MOF on Nd 3+ ‐sensitized upconversion nanoparticles to achieve Janus nanostructures with further...
Thu Nov 21, 2019 17:29
Applications of zeolites in catalysis are plagued by strong diffusion resistance, which results from limitations to molecular transport in micropores, across external crystal surfaces, but also across internal interfaces. The first type of diffusion resistance is well understood, the second is receiving increasing attention, while the diffusion barriers at internal interfaces remain largely unclear. We take Pt/Beta catalyzed isomerization of n ‐heptane as the model system to explore the role of...
Thu Nov 21, 2019 17:29
Gadolinium‐based contrast agents (GBCAs) are used to provide diagnostic information in clinical magnetic resonance (MR) examinations. Gadolinium (Gd) has been detected in the brain, bone and skin of patients, months and years following GBCA administration, raising concerns about long term toxicity. Despite increased scrutiny, the concentration, chemical form and fate of the retained gadolinium species remain unknown. Importantly, the whole body biodistribution and organ clearance of GBCAs is poorly...
Thu Nov 21, 2019 16:54
We report a concise and versatile total synthesis of the diterpenoid (+)‐norcembrene 5 from simple building blocks. A ring‐closing metathesis as well as an auxiliary‐directed 1,4‐addition represent the key steps of our synthetic route. During the synthesis, an unprecedented, highly oxidized pentacyclic structure motif was established from a furanocembranoid via transannular [4+2] cycloaddition.
Thu Nov 21, 2019 15:54
Temporal and spatial control over polydopamine formation on the nanoscale can be achieved by installing an irradiation‐sensitive polymerization system on DNA origami. Precisely distributed G‐quadruplex structures on the DNA template serve as anchors for embedding the photosensitizer protoporphyrin IX, which — upon the irradiation with visible light — induces a multistep oxidation from dopamine to polydopamine, producing polymeric structures on designated areas within the origami framework. The photochemical...
Thu Nov 21, 2019 13:53
Beyond conventional batteries: This Review presents the development history and state of the art of DIBs and presents the reaction kinetics and corresponding critical issues including the various anionic intercalation mechanisms of cathodes, and the reactions at the anodes, including intercalation and alloying, to explore promising strategies towards low‐cost DIBs with high performance. Abstract Rocking‐chair based lithium‐ion batteries (LIBs) have extensively applied to consumer electronics...
Thu Nov 21, 2019 12:42
Remote stabilization: Chiral bicyclic hydrazides catalyze cyclizations of (Z)‐polyenes to cis‐decalins by means of iminium‐ion catalysis. High enantioselectivity results from remote stabilization of the developing cationic charge in the transition state by the hydrazide carbonyl. Abstract Polyene cyclizations offer rapid entry into terpenoid ring systems. Although enantioselective cyclizations of (E)‐polyenes to form trans‐decalin ring systems are well precedented, highly enantioselective cyclizations...
Thu Nov 21, 2019 12:39
Striking a happy medium: “Capture‐collapse” heterocyclizations of aminocyclopropanes equipped with pendant nucleophiles have been used to generate eight‐membered rings. The strategy relies on intramolecular “capture” of a rhodacyclopentanone intermediate by an aryl or N‐based nucleophile followed by C−C or C−N bond‐forming “collapse” to the targets. Abstract Aminocyclopropanes equipped with pendant nucleophiles undergo carbonylative heterocyclization triggered by C−C bond activation to generate...
Thu Nov 21, 2019 12:38
A two‐state (neutral and reduced) stable, electron‐accepting material and its radical anion are presented. The formed radical anion ([FV‐PDI].−) shows remarkable stability and near‐infrared absorptions extending to 1200 nm. Single‐crystal X‐ray diffraction analyses revealed that these two states have significantly different molecular shapes and packing arrangements. Abstract The first example of a two‐state (neutral and reduced), stable electron‐accepting material and its radical anion is presented....
Thu Nov 21, 2019 12:37
For in vivo detection of β‐galactosidase activity in mammals the imaging agent was injected intraperitoneally into transgenic LacZ mice and global signal enhancement was observed 1 h post injection. At 24 h, the MR signal returned to baseline suggesting that the agent is cleared renally. No signal enhancement is observed in non‐transgenic native control mice. Abstract Our lab has developed a new series of self‐immolative MR agents for the rapid detection of enzyme activity in mouse models expressing...
Thu Nov 21, 2019 12:35
Conquering new frontiers: A neural network learning from literature precedents matched onto high‐quality reaction rules offers high accuracy in guiding retrosynthetic choices. This accuracy is retained not only for popular but also for rarely reported yet useful reactions. Abstract When computers plan multistep syntheses, they can rely either on expert knowledge or information machine‐extracted from large reaction repositories. Both approaches suffer from imperfect functions evaluating reaction...
Thu Nov 21, 2019 12:35
Embedding enzyme within MOFs exoskeleton (enzyme@MOFs) offers exciting and elegant opportunities to improve the inherent fragile nature of the enzyme. It not only allows to extending the lifetime of the enzymes, but also imparts the novel biofunctionality to the MOFs. Despite the remarkable stability of MOFs‐embedded enzyme is achieved, limited consideration has been given to the embedding patterns and the conversion of the enzymatic biofunctionality after entrapment by a MOFs. Herein, we for the...
Thu Nov 21, 2019 11:59
3D printing, on all scales, is currently a vibrant topic in scientific and industrial research as it has enormous potential to radically change manufacturing. Due to the inherent nature of the manufacturing process, 3D printed structures may require additional material to structurally support complex features. Such support material must be removed after printing – sometimes termed subtractive manufacturing – without adversely affecting the remaining structure. An elegant solution is the use of photoresists...
Thu Nov 21, 2019 11:53
Cyclophanes are a venerable class of macrocyclic and cage compounds that often contain unusual conformations, high strain, and unusual properties. However, synthesis of complex, functional derivatives remains difficult due to low functional group tolerance, high dilution, extreme reaction conditions, and sometimes low yields using traditional stepwise synthetic methods. “Design of experiments” (DOE) is a method employed for the optimization of reaction conditions, and we showcase this approach to...
Wed Nov 20, 2019 22:24
A rhodium(I)‐BINAP‐catalyzed highly enantioselective [2+2+2] cycloaddition of enynes with alkynes has been developed. Diverse fused tricyclic hydronaphthofuran scaffolds with three consecutive stereogenic centers were constructed in one step from easily available materials with excellent chemo‐, regio‐, diastereo‐, and enantioselectivities. Notable features of these reactions include 100% atom‐economy, very broad scope, and mild reaction conditions.
Wed Nov 20, 2019 20:56
Protein subunits of a low aspect ratio (width over length) with stimuli‐responsiveness are hallmark building blocks of spherical viruses. The interaction of these repeating subunits enables hierarchical assembly for genome packaging and sequential disassembly for optimal genome release. Here, we mimicked these features and constructed a functional spherical artificial virus. The rationally designed 22‐amino‐acid peptide containing pH‐sensitive histidines and aromatic residues self‐assembled into...
Wed Nov 20, 2019 20:55
Bioactive natural products underpin the intriguing pollination strategy used by sexually deceptive orchids. These compounds, which mimic the sex pheromones of the female insect, are emitted in particular blends to lure male insect pollinators of specific species. By combining methods from field biology, analytical chemistry, electrophysiology, crystallography, and organic synthesis, we report that an undescribed β‐hydroxylactone, in combination with two specific hydroxymethylpyrazines, act as pollinator...
Wed Nov 20, 2019 17:00
Abstract Purpose Maturity-onset diabetes of the young type 3 (MODY 3) is a consequence of heterozygous germline mutations in HNF1A, and a subtype of hepatocellular adenoma (HCA) is caused by biallelic somatic HNF1A mutations; rare HCA may be related to MODY 3. This study aimed to investigate the cosegregation of HNF1A mutations with diabetes and HCA in two families. Methods ...
Thu Nov 21, 2019 02:00
What individual differences in neural activity predict the future escalation of alcohol drinking from casual to compulsive? The neurobiological mechanisms that gate the transition from moderate to compulsive drinking remain poorly understood. We longitudinally tracked the development of compulsive drinking across a binge-drinking experience in male mice. Binge drinking unmasked individual differences, revealing latent traits in alcohol consumption and compulsive drinking despite equal prior exposure...
Thu Nov 21, 2019 20:39
The tumor suppressor folliculin (FLCN) enables nutrient-dependent activation of the mechanistic target of rapamycin complex 1 (mTORC1) protein kinase via its guanosine triphosphatase (GTPase) activating protein (GAP) activity toward the GTPase RagC. Concomitant with mTORC1 inactivation by starvation, FLCN relocalizes from the cytosol to lysosomes. To determine the lysosomal function of FLCN, we reconstituted the human lysosomal FLCN complex (LFC) containing FLCN, its partner FLCN-interacting protein...
Thu Nov 21, 2019 20:39
What is universal about music, and what varies? We built a corpus of ethnographic text on musical behavior from a representative sample of the world’s societies, as well as a discography of audio recordings. The ethnographic corpus reveals that music (including songs with words) appears in every society observed; that music varies along three dimensions (formality, arousal, religiosity), more within societies than across them; and that music is associated with certain behavioral contexts such as...
Thu Nov 21, 2019 20:39
Aliphatic amines strongly coordinate, and therefore easily inhibit, the activity of transition-metal catalysts, posing a marked challenge to nitrogen-hydrogen (N–H) insertion reactions. Here, we report highly enantioselective carbene insertion into N–H bonds of aliphatic amines using two catalysts in tandem: an achiral copper complex and chiral amino-thiourea. Coordination by a homoscorpionate ligand protects the copper center that activates the carbene precursor. The chiral amino-thiourea catalyst...
Thu Nov 21, 2019 20:39
The Hippo signaling pathway and its two downstream effectors, the YAP and TAZ transcriptional coactivators, are drivers of tumor growth in experimental models. Studying mouse models, we show that YAP and TAZ can also exert a tumor-suppressive function. We found that normal hepatocytes surrounding liver tumors displayed activation of YAP and TAZ and that deletion of Yap and Taz in these peritumoral hepatocytes accelerated tumor growth. Conversely, experimental hyperactivation of YAP in peritumoral...
Thu Nov 21, 2019 20:39
Controlling the crystal structure is a powerful approach for manipulating the fundamental properties of solids. In van der Waals materials, this control can be achieved by modifying the stacking order through rotation and translation between the layers. Here, we observed stacking-dependent interlayer magnetism in the two-dimensional (2D) magnetic semiconductor chromium tribromide (CrBr3), which was enabled by the successful growth of its monolayer and bilayer through molecular beam epitaxy. Using...
Thu Nov 21, 2019 20:39
Intelligent machines using machine learning algorithms are ubiquitous, ranging from simple data analysis and pattern recognition tools to complex systems that achieve superhuman performance on various tasks. Ensuring that they do not exhibit undesirable behavior—that they do not, for example, cause harm to humans—is therefore a pressing problem. We propose a general and flexible framework for designing machine learning algorithms. This framework simplifies the problem of specifying and regulating...
Thu Nov 21, 2019 20:39
Legumes develop root nodules in symbiosis with nitrogen-fixing rhizobial bacteria. Rhizobia evoke cell division of differentiated cortical cells into root nodule primordia for accommodating bacterial symbionts. In this study, we show that NODULE INCEPTION (NIN), a transcription factor in Lotus japonicus that is essential for initiating cortical cell divisions during nodulation, regulates the gene ASYMMETRIC LEAVES 2-LIKE 18/LATERAL ORGAN BOUNDARIES DOMAIN 16a (ASL18/LBD16a). Orthologs of ASL18/LBD16a...
Thu Nov 21, 2019 20:39
We report a time-calibrated stratigraphic section in Colorado that contains unusually complete fossils of mammals, reptiles, and plants and elucidates the drivers and tempo of biotic recovery during the poorly known first million years after the Cretaceous–Paleogene mass extinction (KPgE). Within ~100 thousand years (ka) post-KPgE, mammalian taxonomic richness doubled, and maximum mammalian body mass increased to near pre-KPgE levels. A threefold increase in maximum mammalian body mass and dietary...
Thu Nov 21, 2019 20:39
Strange or bad metallic transport, defined by incompatibility with the conventional quasiparticle picture, is a theme common to many strongly correlated materials, including high-temperature superconductors. The Hubbard model represents a minimal starting point for modeling strongly correlated systems. Here we demonstrate strange metallic transport in the doped two-dimensional Hubbard model using determinantal quantum Monte Carlo calculations. Over a wide range of doping, we observe resistivities...
Thu Nov 21, 2019 20:39
The pleiotropic host resistance factor SLC11A1 (NRAMP1) defends against diverse intracellular pathogens in mammals by yet-unknown mechanisms. We compared Salmonella infection of coisogenic mice with different SLC11A1 alleles. SLC11A1 reduced Salmonella replication and triggered up-regulation of uptake systems for divalent metal cations but no other stress responses. SLC11A1 modestly diminished iron availability and acutely restricted Salmonella access to magnesium. Growth of Salmonella cells in the...
Thu Nov 21, 2019 20:39
Understanding how novel complex traits originate is a foundational challenge in evolutionary biology. We investigated the origin of prothoracic horns in scarabaeine beetles, one of the most pronounced examples of secondary sexual traits in the animal kingdom. We show that prothoracic horns derive from bilateral source tissues; that diverse wing genes are functionally required for instructing this process; and that, in the absence of Hox input, prothoracic horn primordia transform to contribute to...
Thu Nov 21, 2019 20:39
The metabolic characteristics of tumors present considerable hurdles to immune cell function and cancer immunotherapy. Using a glutamine antagonist, we metabolically dismantled the immunosuppressive microenvironment of tumors. We demonstrate that glutamine blockade in tumor-bearing mice suppresses oxidative and glycolytic metabolism of cancer cells, leading to decreased hypoxia, acidosis, and nutrient depletion. By contrast, effector T cells responded to glutamine antagonism by markedly up-regulating...
Thu Nov 21, 2019 20:39
Sensing and responding to signals is a fundamental ability of living systems, but despite substantial progress in the computational design of new protein structures, there is no general approach for engineering arbitrary new protein sensors. Here, we describe a generalizable computational strategy for designing sensor-actuator proteins by building binding sites de novo into heterodimeric protein-protein interfaces and coupling ligand sensing to modular actuation through split reporters. Using this...
Thu Nov 21, 2019 20:39
Lithium-ion batteries, which power portable electronics, electric vehicles, and stationary storage, have been recognized with the 2019 Nobel Prize in chemistry. The development of nanomaterials and their related processing into electrodes and devices can improve the performance and/or development of the existing energy storage systems. We provide a perspective on recent progress in the application of nanomaterials in energy storage devices, such as supercapacitors and batteries. The versatility of...
Thu Nov 21, 2019 20:39
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