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Abstract The first near IR fluorescent probe for the chemoselective and enantioselective recognition of arginine in aqueous solution is reported in this work. This probe, made of a 1,1’‐binaphthyl‐based chiral aldehyde unit and a rhodamine‐based near IR chromophore, in combination with La³⁺exhibits highly chemoselective as well as enantioselective fluorescent enhancement with arginine at λ=764 nm upon excitation at λ=690 nm. Little or no fluorescent response is observed toward the chirality miss‐matched arginine enantiomer or other common amino acids and their enantiomers. This probe also allows visual discrimination of the arginine enantiomers because of its fast and distinct color change upon interaction with the substrate. 

INTRODUCTION Thousands of genetic variants have been associated with human diseases and traits through genome-wide association studies (GWASs). Translating these discoveries into improved therapeutics requires discerning which variants among hundreds of candidates are causally related to disease risk. To date, only a handful of causal variants have been confirmed. Here, we leverage 100 million years of mammalian evolution to address this major challenge. RATIONALE We compared genomes from hundreds of mammals and identified bases with unusually few variants (evolutionarily constrained). Constraint is a measure of functional importance that is agnostic to cell type or developmental stage. It can be applied to investigate any heritable disease or trait and is complementary to resources using cell type– and time point–specific functional assays like Encyclopedia of DNA Elements (ENCODE) and Genotype-Tissue Expression (GTEx). RESULTS Using constraint calculated across placental mammals, 3.3% of bases in the human genome are significantly constrained, including 57.6% of coding bases. Most constrained bases (80.7%) are noncoding. Common variants (allele frequency ≥ 5%) and low-frequency variants (0.5% ≤ allele frequency < 5%) are depleted for constrained bases (1.85 versus 3.26% expected by chance, P < 2.2 × 10 −308 ). Pathogenic ClinVar variants are more constrained than benign variants ( P < 2.2 × 10 −16 ). The most constrained common variants are more enriched for disease single-nucleotide polymorphism (SNP)–heritability in 63 independent GWASs. The enrichment of SNP-heritability in constrained regions is greater (7.8-fold) than previously reported in mammals and is even higher in primates (11.1-fold). It exceeds the enrichment of SNP-heritability in nonsynonymous coding variants (7.2-fold) and fine-mapped expression quantitative trait loci (eQTL)–SNPs (4.8-fold). The enrichment peaks near constrained bases, with a log-linear decrease of SNP-heritability enrichment as a function of the distance to a constrained base. Zoonomia constraint scores improve functionally informed fine-mapping. Variants at sites constrained in mammals and primates have greater posterior inclusion probabilities and higher per-SNP contributions. In addition, using both constraint and functional annotations improves polygenic risk score accuracy across a range of traits. Finally, incorporating constraint information into the analysis of noncoding somatic variants in medulloblastomas identifies new candidate driver genes. CONCLUSION Genome-wide measures of evolutionary constraint can help discern which variants are functionally important. This information may accelerate the translation of genomic discoveries into the biological, clinical, and therapeutic knowledge that is required to understand and treat human disease. Using evolutionary constraint in genomic studies of human diseases. ( A ) Constraint was calculated across 240 mammal species, including 43 primates (teal line). ( B ) Pathogenic ClinVar variants ( N = 73,885) are more constrained across mammals than benign variants ( N = 231,642; P < 2.2 × 10 −16 ). ( C ) More-constrained bases are more enriched for trait-associated variants (63 GWASs). ( D ) Enrichment of heritability is higher in constrained regions than in functional annotations (left), even in a joint model with 106 annotations (right). ( E ) Fine-mapping (PolyFun) using a model that includes constraint scores identifies an experimentally validated association at rs1421085. Error bars represent 95% confidence intervals. BMI, body mass index; LF, low frequency; PIP, posterior inclusion probability. 

Abstract Efficient mass transport and selective salt rejection are highly desirable for solar or thermally driven seawater desalination, but its realization is challenging. Here a new liquid supply mechanism is proposed, i.e., ionic pumping effect, using a polyelectrolyte hydrogel foam (PHF), demonstrated with poly(sodium acrylate) [P(SA)] embedded in a microporous carbon foam (CF). The PHF simultaneously possesses high osmotic pressure for liquid transport and a strong salt‐rejection effect. The PHF is able to sustain high flux of ≈24 L per m²per hour (LMH), comparable to the evaporative flux under 15 suns, and a salt rejection ratio over 80%. Compared to the porous carbon foam without the polyelectrolyte hydrogel, i.e., with only the capillary pumping effect, the PHF yields a 42.4% higher evaporative flux, at ≈1.6 LMH with DI water and ≈1.3 LMH with simulated seawater under one‐sun condition due to the more efficient ionic liquid pumping. More importantly, thanks to the strong salt‐rejection effect, the PHF shows a continuous and stable solar‐driven desalination flux of ≈1.3 LMH under one‐sun over 72 h, which has not been achieved before. The successful demonstration of both efficient ionic pumping and strong salt rejection effects makes the PHF an attractive platform for sustainable solar‐driven desalination. 

Fibers capable of generating axial contraction are commonly seen in nature and engineering applications. Despite the broad applications of fiber actuators, it is still very challenging to fabricate fiber actuators with combined large actuation strain, fast response speed, and high power density. Here, we report the fabrication of a liquid crystal elastomer (LCE) microfiber actuators using a facile electrospinning technique. Owing to the extremely small size of the LCE microfibers, they can generate large actuation strain (~60 percent) with a fast response speed (<0.2 second) and a high power density (400 watts per kilogram), resulting from the nematic-isotropic phase transition of liquid crystal mesogens. Moreover, no performance degradation is detected in the LCE microfibers after 10⁶cycles of loading and unloading with the maximum strain of 20 percent at high temperature (90 degree Celsius). The small diameter of the LCE microfiber also results in a self-oscillatory behavior in a steady temperature field. In addition, with a polydopamine coating layer, the actuation of the electrospun LCE microfiber can be precisely and remotely controlled by a near-infrared laser through photothermal effect. Using the electrospun LCE microfiber actuator, we have successfully constructed a microtweezer, a microrobot, and a light-powered microfluidic pump. 

Abstract The semiconductor tracker (SCT) is one of the tracking systems for charged particles in the ATLAS detector. It consists of 4088 silicon strip sensor modules.During Run 2 (2015–2018) the Large Hadron Collider delivered an integrated luminosity of 156 fb -1 to the ATLAS experiment at a centre-of-mass proton-proton collision energy of 13 TeV. The instantaneous luminosity and pile-up conditions were far in excess of those assumed in the original design of the SCT detector.Due to improvements to the data acquisition system, the SCT operated stably throughout Run 2.It was available for 99.9% of the integrated luminosity and achieved a data-quality efficiency of 99.85%.Detailed studies have been made of the leakage current in SCT modules and the evolution of the full depletion voltage, which are used to study the impact of radiation damage to the modules.