Publications by authors named "Juntian Wu"

The transition of chemistry into biology is poorly understood. Key questions include how the inherently divergent nature of chemical reactions can be curtailed, and whether Darwinian principles from biology extend to chemistry. Addressing both questions simultaneously, we now show that the evolutionary principle of competitive exclusion, which states that a single niche can be stably occupied by only one species, also applies to self-replicating chemical systems, and that this principle diminishes the tendency of chemistry to diversify.

View Article and Find Full Text PDF

Self-replicating molecules and well-defined folded macromolecules are of great significance in the emergence and evolution of life. How they may interconnect and affect each other remains largely elusive. Here, we demonstrate an abiotic system where a single building block can oligomerize to yield either a self-replicating molecule or a foldamer.

View Article and Find Full Text PDF

Systems chemistry has emerged as a useful paradigm to access structures and phenomena typically exhibited by living systems, including complex molecular systems such as self-replicators and foldamers. As we progress further toward the noncovalent synthesis of life-like systems, and eventually life itself, it is necessary to gain control over assembly pathways. Dissipative chemical fueling has enabled access to stable populations of (self-assembled) structures that would normally form only transiently.

View Article and Find Full Text PDF

Fuelled chemical systems have considerable functional potential that remains largely unexplored. Here we report an approach to transient amide bond formation and use it to harness chemical energy and convert it to mechanical motion by integrating dissipative self-assembly and the Marangoni effect in a source-sink system. Droplets are formed through dissipative self-assembly following the reaction of octylamine with 2,3-dimethylmaleic anhydride.

View Article and Find Full Text PDF
Article Synopsis
  • In Singapore, there’s a growing problem with people who go to Emergency Departments (EDs) often because of alcohol-related issues, and they don’t use regular addiction treatment.
  • This study is looking at a new method called Assertive Community Treatment (ACT) to see if it can help reduce their ED visits and improve their overall health.
  • The research compares the health outcomes of these frequent visitors before and after they receive ACT compared to regular emergency care, while tracking their progress over six months.
View Article and Find Full Text PDF

Copying information is vital for life's propagation. Current life forms maintain a low error rate in replication, using complex machinery to prevent and correct errors. However, primitive life had to deal with higher error rates, limiting its ability to evolve.

View Article and Find Full Text PDF

Darwinian evolution involves the inheritance and selection of variations in reproducing entities. Selection can be based on, among others, interactions with the environment. Conversely, the replicating entities can also affect their environment generating a reciprocal feedback on evolutionary dynamics.

View Article and Find Full Text PDF

Dynamic foldamers are synthetic folded molecules which can change their conformation in response to an external stimulus and are currently at the forefront of foldamer chemistry. However, constitutionally dynamic foldamers, which can change not only their conformation but also their molecular constitution in response to their environment, are without precedent. We now report a size- and shape-switching small dynamic covalent foldamer network which responds to changes in pH.

View Article and Find Full Text PDF

Among the key characteristics of living systems are their ability to self-replicate and the fact that they exist in an open system away from equilibrium. Herein, we show how the outcome of the competition between two self-replicators, differing in size and building block composition, is different depending on whether the experiments are conducted in a closed vial or in an open and out-of-equilibrium replication-destruction regime. In the closed system, the slower replicator eventually prevails over the faster competitor.

View Article and Find Full Text PDF

The two-dimensional (2D) self-assembly behavior of an asymmetric thienophenanthrene derivative (M1) has been theoretically predicted and further probed via STM. The barely exploited Brπ halogen bonds play an assisting role in the structural formation, and a strong cooperative effect from the C-HBr bonds is shown. Such π-type halogen bond assisted self-assembly reveals self-adaption properties, which is of great interest for flexible light-emitting devices and self-healing materials.

View Article and Find Full Text PDF

Recent research studies have shown that the halogenated benzo[1,2-b:4,5-b']dithiophene (DTBDT) unit as a polymer donor exhibits high charge carrier mobility due to the well-ordered molecular packing and high crystallinity, which is meaningful for achieving highly efficient organic solar cells (OSCs). However, it is difficult to acquire the accurate packing information of polymer materials. Herein, we investigated the self-assembled behaviors of two DTBDT derivatives, 4,8-bis(4-octadecylthiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene (H-DTBDT) and 4,8-bis(5-bromo-4-octadecylthiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene (Br-DTBDT), to elucidate the effect of introducing a bromine atom on molecular packing structures by STM at the 1-phenyloctane/HOPG interface.

View Article and Find Full Text PDF

Owing to a wide range of applications within the areas such as chiral sensors, enantiomeric resolution, and asymmetric catalysis, understanding chiral adsorption phenomena at the interface is thereby of great importance. In particular, the role of multiple hydrogen bonds in inducing chiral diversiform morphologies has never been systematically investigated. Herein, by delicate control of the volume ratio of 1-octanoic acid and 1-octanol as the mixed solvent, a series of self-assembled nanostructures of 2-hydroxyl-7-pentadecyloxy-fluorenone (HPF) were sequentially fabricated, including the achiral densely-packed pattern, the chiral "6-2" pattern, the chiral alternate pattern, and the chiral double-rosette pattern.

View Article and Find Full Text PDF

Two-dimensional supramolecular assemblies of a series of 2,7-bis(10-n-alkoxycarbonyl-decyloxy)-9-fluorenone derivatives (BAF-Cn, n = 1, 3-6) consisting of polar fluorenone moieties and ester alkoxy chains were investigated by scanning tunneling microscopy on highly oriented pyrolytic graphite surfaces. The chain-length effect was observed in the self-assembly of BAF-Cn. Self-assembly of BAF-C1 was composed of a linear I pattern, where the side chains adopted a fully interdigitated arrangement.

View Article and Find Full Text PDF

A PHP Error was encountered

Severity: Warning

Message: fopen(/var/lib/php/sessions/ci_sessionf0cjjisehtscl9l4a2qoku4uttqet19s): Failed to open stream: No space left on device

Filename: drivers/Session_files_driver.php

Line Number: 177

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: session_start(): Failed to read session data: user (path: /var/lib/php/sessions)

Filename: Session/Session.php

Line Number: 137

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once