In this report I propose to examine the concept of the ‘smart city’ from the standpoint of spatial enablement. I analyse emerging research on smart cities, particularly those addressing the potential ...role of GISciences in the development and implementation of the concept of smart cities. I develop the idea that the intelligence of a city should be measured by its ability to produce favourable conditions to get urban operators (citizens, organizations, private companies, etc.) actively involved into sociospatial innovation dynamics. To obtain such a commitment, I believe that operators should be able to develop and mobilize (digital) spatial skills so that they could efficiently manage their spatiality. In other words, I argue that a smart city is first of all a spatially enabled city.
This second report is dedicated to the concept of ‘place’ revisited in the context of smart cities. Some recent studies suggest that today’s digital cities rely more on an approach to the urban ...context based on a network of connected places than on an approach to the city built on areal spaces. Does it mean that there are more places and fewer spaces in spatially enabled cities? Is the intelligence of a city mainly related to its ability to sound out the genesis of urban places? These issues raise questions about the design of spatial models used to build GIS, as well as place-based urban design methods and tools. This second report explores these questions from the standpoint of GISciences.
This third report examines interfaces as a key element enabling spatial skills, and development of new forms of digital spatialities for smart cities. Digital technology is becoming consubstantial to ...urban materiality, but map interfaces are particularly central tools for indexing (geographic) knowledge and expertise, accessing informational components of digital cities, and actively engaging digital dimensions of urban places.
Evolution in the field of the total synthesis of natural products has led to exciting developments over the last decade. Numerous chemoselective and enantioselective methodologies have emerged from ...total syntheses, resulting in efficient access to many important natural product targets. This Review highlights recent developments concerning dearomatization, a powerful strategy for the total synthesis of architecturally complex natural products wherein planar, aromatic scaffolds are converted to three‐dimensional molecular architectures.
1, 2, …︁ 3 dearomaticity: The conversion of planar, aromatic scaffolds (arenes, phenols, and heteroarenes) into three‐dimensional molecular architectures is a powerful strategy for the total synthesis of complex natural products. This Review highlights recent developments and outlines future perspectives and opportunities for catalytic, enantioselective dearomatization processes.
A biomimetic semisynthesis of the diterpenoid (+)-providencin (
) and the unexpected novel C14 regioisomer
was achieved by photoirradiation of the proposed biosynthetic cembranoid precursor ...(-)-bipinnatin E (
). The absolute configuration assignments of
and
by correlation were established by X-ray analysis. A combination of NOESY data and photochemical reaction results revealed that both C2 and C14 positions of the macrocycle (-)-
are suitable for hydrogen abstraction, thus affording an explanation to the mixture of cyclobutane photoproduct isomers obtained by a Norrish-Yang cyclization. These results also support the proposed biosynthetic hypothesis describing the genuine photochemical transformation of (-)-
into (+)-
, without refuting that both regioisomer products
/
might be artifacts of isolation.
The ribosome is centrally situated to sense metabolic states, but whether its activity, in turn, coherently rewires transcriptional responses is unknown. Here, through integrated chemical-genetic ...analyses, we found that a dominant transcriptional effect of blocking protein translation in cancer cells was inactivation of heat shock factor 1 (HSF1), a multifaceted transcriptional regulator of the heat-shock response and many other cellular processes essential for anabolic metabolism, cellular proliferation, and tumorigenesis. These analyses linked translational flux to the regulation of HSF1 transcriptional activity and to the modulation of energy metabolism. Targeting this link with translation initiation inhibitors such as rocaglates deprived cancer cells of their energy and chaperone armamentarium and selectively impaired the proliferation of both malignant and premalignant cells with early-stage oncogenic lesions.
We report a chiral-squaramide-catalyzed enantio- and diastereoselective synthesis of α-allyl amino esters. The optimized protocol provides access to
-carbamoyl-protected amino esters via nucleophilic ...allylation of readily accessible α-chloro glycinates. A variety of useful α-allyl amino esters were prepared, including crotylated products bearing vicinal stereocenters that are inaccessible through enolate alkylation, with high enantioselectivity (up to 97% ee) and diastereoselectivity (>10:1). The reactions display first-order kinetic dependence on both the α-chloro glycinate and the nucleophile, consistent with rate-limiting C-C bond formation. Computational analysis of the uncatalyzed reaction predicts an energetically inaccessible iminium intermediate, and a lower energy concerted S
2 mechanism.
In response to the current Coronavirus SARS-CoV-2 pandemic, many countries are developing digital strategies for the identification of individuals who have been in contact with infected persons. ...Those strategies are mainly based on Contact Tracing applications. While the effectiveness of these technologies has not yet been demonstrated, and that their deployment conditions remain socially complex, they raise serious ethical questions. This paper presents an overview of the development of Contact Tracing and, suggests a reflection and possible solutions for their ethical and sustainable deployment through a more active and transparent citizen engagement.
Despite their pivotal role in defining antibody affinity and protein function, β-hairpins harboring long noncanonical loops remain synthetically challenging because of the large entropic penalty ...associated with their conformational folding. Little is known about the contribution and impact of stabilizing motifs on the folding of β-hairpins with loops of variable length and plasticity. Here, we report a design of minimalist β-straps (strap = strand + cap) that offset the entropic cost of long-loop folding. The judicious positioning of noncovalent interactions (hydrophobic cluster and salt-bridge) within the novel 8-mer β-strap design RW(V/H)W···WVWE stabilizes hairpins with up to 10-residue loops of varying degrees of plasticity (
up to 52 °C; 88 ± 1% folded at 18 °C). This "hyper" thermostable β-strap outperforms the previous gold-standard technology of β-strand-β-cap (16-mer) and provides a foundation for producing new classes of long hairpins as a viable and practical alternative to macrocyclic peptides.
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