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Hierarchical self‐assembly represents a powerful strategy for the fabrication of functional materials across various length scales. However, achieving precise formation of functional hierarchical assemblies remains a significant challenge and requires a profound understanding of molecular assembly interactions. In this study, we present a molecular‐level understanding of the hierarchical assembly of sequence‐defined peptoids into multidimensional functional materials, including twisted nanotube bundles serving as a highly efficient artificial light harvesting system. By employing synchrotron‐based powder X‐ray diffraction and analyzing single crystal structures of model compounds, we elucidated the molecular packing and mechanisms underlying the assembly of peptoids into multidimensional nanostructures. Our findings demonstrate that incorporating aromatic functional groups, such as tetraphenyl ethylene (TPE), at the termini of assembling peptoid sequences promotes the formation of twisted bundles of nanotubes and nanosheets, thus enabling the creation of a highly efficient artificial light harvesting system. This research exemplifies the potential of leveraging sequence‐defined synthetic polymers to translate microscopic molecular structures into macroscopic assemblies. It holds promise for the development of functional materials with precisely controlled hierarchical structures and designed functions. [ABSTRACT FROM AUTHOR]

Following the co‐precipitation method for producing terbium orthoferrite (TbFeO3), the final products were denoted as TbFeO3‐650, −750, and −850. A single‐phase of orthorhombic TbFeO3 crystals (o‐TbFeO3) was obtained with a calcination temperature of up to 850 °C, while in the range of 650–750 °C there was still a small amount of terbium and iron oxide phases. The average size of o‐TbFeO3 crystallites for the TbFeO3‐850 sample was about 76 nm and was larger than that of TbFeO3‐650 (~45 nm) and TbFeO3‐750 (~47 nm). The o‐TbFeO3 crystal structure in all samples was found to be distorted. In the applied field from −15 to +15 kOe, all of the samples had low values of coercive field (5–11 ⋅ 10−3 Oe) but high values of net magnetization (2.06–2.40 emu ⋅ g−1); the samples appeared to behave as paramagnetic materials. It was shown that the TbFeO3‐850 sample has slightly better magnetic properties than the two others. An average grain size of about 79 nm was found in the TbFeO3‐850 sample, which exhibited a morphology of sphere‐like shapes with highly agglomerated grains. The TbFeO3‐850 sample demonstrated a high absorbance at wavelengths of 400–600 nm, with a direct bandgap of about 2.68 eV. [ABSTRACT FROM AUTHOR]

Climate change impacts ocean nutrient availability and will likely alter the marine food web. While climate models predict decreased average ocean productivity, the extent of these changes, especially in the marginal seas upon which large human populations depend, is not well understood. Here, we reconstructed changes in seawater phosphate concentration and nitrate source over the past 400 years, which reveals a more than 50% decline in residence time of seawater phosphate, and 8%–48% decline in subsurface nitrogen supply following the coldest period of Little Ice Age. Our data indicates a link between surface ocean nutrient supply and the East Asian Summer Monsoon strength in an economically important marginal sea. As climate models predict that the East Asian Summer monsoon will strengthen in the future, our study implies that surface ocean primary productivity may increase in the South China Sea, contrary to the predicted decrease in global average ocean productivity. Plain Language Summary: Global climate models predict that surface ocean nutrient concentrations will significantly decrease over the next 100 years as our climate changes. However, in the world's marginal seas, which human populations depend on most heavily for food security, the surface ocean biogeochemical changes are still difficult to predict with global‐scale models. Here, using coral‐based paleoclimate proxies, we reconstruct changes to surface phosphate concentration and to sources of surface nitrogen over the past four centuries in the South China Sea (SCS). Combined with box model simulations, our data reveal a more than 50% decline in phosphate residence time and an 8%–48% decline in subsurface nitrate supply from the 1600s to present. Such a decline implies a significant decrease in primary productivity and likely a community shift toward nitrogen‐fixing phytoplankton. Importantly, our data indicate that the decrease in nutrient supply was driven by weakened monsoon‐induced upwelling, demonstrating strong ties between nutrient supply and monsoon strength in the SCS. Climate change is predicted to strengthen the East Asian Summer Monsoon, and our results suggest that primary productivity in this economically important region may increase, contrary to the widely predicted decreases in average global ocean productivity. Key Points: Coral skeletal phosphorus content with scattered nitrogen isotopes is reconstructed over the past 400 yearsNutrient supply declined up to 48% since the Little Ice Age in the western South China SeaThe coral record from links nutrient supply to monsoon wind, implying higher productivity under a stronger monsoon in the future [ABSTRACT FROM AUTHOR]

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Two ring size β‐Sugar Amino Acids, βSAAs, Fmoc‐RibAFU(ip)‐OH and Fmoc‐GlcAPU(Me,Bn)‐OH, as Lego‐elements are introduced to make α/β‐chimera peptides by flow‐based solid phase peptide synthesis (SPPS). Their synthesis alongside selected α‐amino acids, αAA, is fine‐tuned. The recently published 50 % TFA cleavage protocol of tBu protected shorter (Ser, Asp) and larger aromatic (Tyr, Trp), with bulky side chain protected Arg(Pbf) and Gln(Trt) residues was probed. We found that this milder condition is sufficient to successfully remove both the 1,2‐O‐isopropylidene from RibAFU(ip) and tBu, Pbf and Trt from the other αAA residues, but to preserve the 2,3‐di‐O‐benzyl protection of GlcAPU(Me,Bn). Note that O‐benzyl groups can be subsequently cleaved by HF or catalytic hydrogenation. Tuned protocols allow the efficient synthesis of 16‐mer penetratin analogues via continuous flow conditions incorporating either RibAFU(ip) or GlcAPU(Me,Bn) βSAAs. Both acid concentration (50 %/95 %) and type (TFA/HF) allow a versatile protecting group removal and thus, to fine‐tune the hydrophilicity and aromaticity of the above building blocks in chimera constructs. [ABSTRACT FROM AUTHOR]

In the search of smarter routes to control the conditions of N‐heterocyclic carbene (NHCs) formation, a two‐component air‐stable NHC photogenerating system is reported. It relies on the irradiation at 365 nm of a mixture of 2‐isopropylthioxanthone (ITX) with 1,3‐bis(mesityl)imidazoli(ni)um tetraphenylborate. The photoinduced liberation of NHC is evidenced by reaction with a mesitoyl radical to form an NHC‐radical adduct detectable by electron spin resonance spectroscopy. The NHC yield can be determined by 1H NMR spectroscopy through the formation of a soluble and stable NHC–carbodiimide adduct. To deprotonate the azolium salt and liberate the NHC, a mechanism is proposed in which the role of base is played by ITX radical anion formed in situ by a primary photoinduced electron‐transfer reaction between electronically excited ITX (oxidant) and BPh4− (reductant). An NHC yield as high as 70 % is achieved upon starting with a stoichiometric ratio of ITX and azolium salt. Three different photoNHC‐mediated polymerizations are described: synthesis of polyurethane and polyester by organocatalyzed step‐growth polymerization and ring‐opening copolymerization, respectively, and generation of polynorbornene by ring‐opening metathesis polymerization using an NHC‐coordinated Ru catalyst formed in situ. [ABSTRACT FROM AUTHOR]

Abstract: 1,3‐Bis(mesityl)imidazolium tetraphenylborate (IMesH+ BPh4−) can be synthesized in one step by anion metathesis between the corresponding imidazolium chloride and sodium tetraphenylborate. In the presence of 2‐isopropylthioxanthone (sensitizer), an IMes N‐heterocyclic carbene (NHC) ligand can be photogenerated under irradiation at 365 nm through coupled electron/proton transfer reactions. By combining this tandem NHC photogenerator system with metathesis inactive [RuCl2(p‐cymene)]2 precatalyst, the highly active RuCl2(p‐cymene)(IMes) complex can be formed in situ, enabling a complete ring‐opening metathesis polymerization (ROMP) of norbornene in the matter of minutes at room temperature. To the best of our knowledge, this is the first example of a photogenerated NHC. Its exploitation in photoROMP has resulted in a simplified process compared to current photocatalysts, because only stable commercial or easily synthesized reagents are required. [ABSTRACT FROM AUTHOR]

Background: Contextual processing (or context processing; CP) is an integral component of cognition. Contextual processing allows people to manage their thoughts and actions by adjusting to surroundings. The process involves the formation of internal representations of context in relation to the environment, maintenance of information over a period of time, and the updating of mental representations to reflect environmental changes. Each of these functions can be affected by aging and associated brain conditions. Here, we update the current research investigating the impact of aging and neurodegeneration on CP. Method: Through searching the PubMed, PsycINFO, and Google Scholar databases, 18 studies that focused on aging, mild cognitive impairment (MCI), Alzheimer's disease (AD), and Parkinson's disease (PD) impacts on CP were retrieved and reviewed in detail. Result: Older adults of normal aging had a delayed onset and reduced amplitude of electrophysiological response to information detection, comparison, and execution. MCI patients demonstrated clear signs of impaired CP compared to normal aging. The only study reporting CP in AD suggested a decreased proactive control in maintaining contextual information, but seemingly intact reactive control. On the other hand, PD without dementia showed limited ability to use contextual information in cognitive and motor processes, exhibiting impaired reactive control. Conclusion: Data suggest that accelerated aging and neurodegeneration can further impact the changes in CP with age, providing insights for improving intervention strategies. This study highlights the need for increased attention to research this important but understudied field. [ABSTRACT FROM AUTHOR]

Baseline epidemiological data are presented from a parasitological survey conducted in Thuy Loi commune, Ha Nam province, Vietnam; a farming community where night soil is routinely used as fertilizer for crops. 177 households were visited and 543 individuals (aged 1–88 years) recruited to the study. Helminth infection intensity was assessed by Kato-Katz to determine the density of parasite eggs per gram of stool (epg). Ascaris lumbricoides, Trichuris trichiura and hookworm infections were the only species detected. 83% of individuals were infected with A. lumbricoides (mean epg = 11971), 94% with T. trichiura (mean epg = 793) and 59% with hookworm (mean epg = 302). Age-dependent patterns of infection prevalence and intensity were similar for A. lumbricoides and T. trichiura, but markedly different for hookworm infection. Similarly, age-dependency in the k-values for the three infections was due to covariance with the respective mean intensities with age rather than to independent age effects, with similar patterns for A. lumbricoides and T. trichiura, and a different pattern for hookworm. Three major conclusions can be drawn from the multiple-species analyses: There is positive interaction between A. lumbricoides and T. trichiura infections; high-intensity A. lumbricoides infections are significantly associated with high-intensity T. trichiura infections; and there is positive interaction between these two species such that infection intensity of A. lumbricoides is higher in individuals with concurrent T. trichiura infection than in individuals without and vice versa. [ABSTRACT FROM AUTHOR]