bluuebunny/crossref_metadata_2025_split huggingface dataset:
Extreme multiexciton emission from deterministically assembled single-emitter subwavelength plasmonic patch antennas
Authors: Dhawan Amit Raj , Belacel Cherif , Esparza-Villa Juan Uriel , Nasilowski Michel , Wang Zhiming , Schwob Catherine , Hugonin Jean-Paul , Coolen Laurent , Dubertret Benoît , Senellart Pascale , Maître Agnès 
Published: March 2020

AbstractCoupling nano-emitters to plasmonic antennas is a key milestone for the development of nanoscale quantum light sources. One challenge, however, is the precise nanoscale positioning of the emitter in the structure. Here, we present a laser etching protocol that deterministically positions a single colloidal CdSe/CdS core/shell quantum dot emitter inside a subwavelength plasmonic patch antenna with three-dimensional nanoscale control. By exploiting the properties of metal–insulator–metal structures at the nanoscale, the fabricated single-emitter antenna exhibits a very high-Purcell factor (>72) and a brightness enhancement of a factor of 70. Due to the unprecedented quenching of Auger processes and the strong acceleration of the multiexciton emission, more than 4 photons per pulse can be emitted by a single quantum dot, thus increasing the device yield. Our technology can be applied to a wide range of photonic nanostructures and emitters, paving the way for scalable and reliable fabrication of ultra-compact light sources.
Comparative performance of rural water supplies during drought
Authors: MacAllister D. J. , MacDonald A. M. , Kebede S. , Godfrey S. , Calow R. 
Published: March 2020

AbstractAs rural African communities experience more frequent and extreme droughts, it is increasingly important that water supplies are climate resilient. Using a unique temporal dataset we explore rural water supply (n = 5196) performance during the 2015–16 drought in Ethiopia. Mean functionality ranged from 60% for motorised boreholes to 75% for hand-pumped boreholes. Real-time monitoring and responsive operation and maintenance led to rapid increases in functionality of hand-pumped and, to a lesser extent, motorised boreholes. Increased demand was placed on motorised boreholes in lowland areas as springs, hand-dug-wells and open sources failed. Most users travelled >1 h to access motorised boreholes but <30 min, increasing to 30-60 mins, for hand-pumped boreholes. Boreholes accessing deep (>30 m) groundwater performed best during the drought. Prioritising access to groundwater via multiple improved sources and a portfolio of technologies, such as hand-pumped and motorised boreholes, supported by responsive and proactive operation and maintenance, increases rural water supply resilience.
Ratiometric population sensing by a pump-probe signaling system in Bacillus subtilis
Authors: Babel Heiko , Naranjo-Meneses Pablo , Trauth Stephanie , Schulmeister Sonja , Malengo Gabriele , Sourjik Victor , Bischofs Ilka B. 
Published: March 2020

AbstractCommunication by means of diffusible signaling molecules facilitates higher-level organization of cellular populations. Gram-positive bacteria frequently use signaling peptides, which are either detected at the cell surface or ‘probed’ by intracellular receptors after being pumped into the cytoplasm. While the former type is used to monitor cell density, the functions of pump-probe networks are less clear. Here we show that pump-probe networks can, in principle, perform different tasks and mediate quorum-sensing, chronometric and ratiometric control. We characterize the properties of the prototypical PhrA-RapA system in Bacillus subtilis using FRET. We find that changes in extracellular PhrA concentrations are tracked rather poorly; instead, cells accumulate and strongly amplify the signal in a dose-dependent manner. This suggests that the PhrA-RapA system, and others like it, have evolved to sense changes in the composition of heterogeneous populations and infer the fraction of signal-producing cells in a mixed population to coordinate cellular behaviors.
Nanoelectromechanical relay without pull-in instability for high-temperature non-volatile memory
Authors: Rana Sunil , Mouro João , Bleiker Simon J. , Reynolds Jamie D. , Chong Harold M. H. , Niklaus Frank , Pamunuwa Dinesh 
Published: March 2020

AbstractEmerging applications such as the Internet-of-Things and more-electric aircraft require electronics with integrated data storage that can operate in extreme temperatures with high energy efficiency. As transistor leakage current increases with temperature, nanoelectromechanical relays have emerged as a promising alternative. However, a reliable and scalable non-volatile relay that retains its state when powered off has not been demonstrated. Part of the challenge is electromechanical pull-in instability, causing the beam to snap in after traversing a section of the airgap. Here we demonstrate an electrostatically actuated nanoelectromechanical relay that eliminates electromechanical pull-in instability without restricting the dynamic range of motion. It has several advantages over conventional electrostatic relays, including low actuation voltages without extreme reduction in critical dimensions and near constant actuation airgap while the device moves, for improved electrostatic control. With this nanoelectromechanical relay we demonstrate the first high-temperature non-volatile relay operation, with over 40 non-volatile cycles at 200 ∘C.
A generalizable 29-mRNA neural-network classifier for acute bacterial and viral infections
Authors: Mayhew Michael B. , Buturovic Ljubomir , Luethy Roland , Midic Uros , Moore Andrew R. , Roque Jonasel A. , Shaller Brian D. , Asuni Tola , Rawling David , Remmel Melissa , Choi Kirindi , Wacker James , Khatri Purvesh , Rogers Angela J. , Sweeney Timothy E. 
Published: March 2020

AbstractImproved identification of bacterial and viral infections would reduce morbidity from sepsis, reduce antibiotic overuse, and lower healthcare costs. Here, we develop a generalizable host-gene-expression-based classifier for acute bacterial and viral infections. We use training data (N = 1069) from 18 retrospective transcriptomic studies. Using only 29 preselected host mRNAs, we train a neural-network classifier with a bacterial-vs-other area under the receiver-operating characteristic curve (AUROC) 0.92 (95% CI 0.90–0.93) and a viral-vs-other AUROC 0.92 (95% CI 0.90–0.93). We then apply this classifier, inflammatix-bacterial-viral-noninfected-version 1 (IMX-BVN-1), without retraining, to an independent cohort (N = 163). In this cohort, IMX-BVN-1 AUROCs are: bacterial-vs.-other 0.86 (95% CI 0.77–0.93), and viral-vs.-other 0.85 (95% CI 0.76–0.93). In patients enrolled within 36 h of hospital admission (N = 70), IMX-BVN-1 AUROCs are: bacterial-vs.-other 0.92 (95% CI 0.83–0.99), and viral-vs.-other 0.91 (95% CI 0.82–0.98). With further study, IMX-BVN-1 could provide a tool for assessing patients with suspected infection and sepsis at hospital admission.
Marker-free carotenoid-enriched rice generated through targeted gene insertion using CRISPR-Cas9
Authors: Dong Oliver Xiaoou , Yu Shu , Jain Rashmi , Zhang Nan , Duong Phat Q. , Butler Corinne , Li Yan , Lipzen Anna , Martin Joel A. , Barry Kerrie W. , Schmutz Jeremy , Tian Li , Ronald Pamela C. 
Published: March 2020

AbstractTargeted insertion of transgenes at pre-determined plant genomic safe harbors provides a desirable alternative to insertions at random sites achieved through conventional methods. Most existing cases of targeted gene insertion in plants have either relied on the presence of a selectable marker gene in the insertion cassette or occurred at low frequency with relatively small DNA fragments (<1.8 kb). Here, we report the use of an optimized CRISPR-Cas9-based method to achieve the targeted insertion of a 5.2 kb carotenoid biosynthesis cassette at two genomic safe harbors in rice. We obtain marker-free rice plants with high carotenoid content in the seeds and no detectable penalty in morphology or yield. Whole-genome sequencing reveals the absence of off-target mutations by Cas9 in the engineered plants. These results demonstrate targeted gene insertion of marker-free DNA in rice using CRISPR-Cas9 genome editing, and offer a promising strategy for genetic improvement of rice and other crops.
Directed self-assembly of viologen-based 2D semiconductors with intrinsic UV–SWIR photoresponse after photo/thermo activation
Authors: Yu Xiao-Qing , Sun Cai , Liu Bin-Wen , Wang Ming-Sheng , Guo Guo-Cong 
Published: March 2020

AbstractExtending photoresponse ranges of semiconductors to the entire ultraviolet–visible (UV)–shortwave near-infrared (SWIR) region (ca. 200–3000 nm) is highly desirable to reduce complexity and cost of photodetectors or to promote power conversion efficiency of solar cells. The observed up limit of photoresponse for organic-based semiconductors is about 1800 nm, far from covering the UV–SWIR region. Here we develop a cyanide-bridged layer-directed intercalation approach and obtain a series of two viologen-based 2D semiconductors with multispectral photoresponse. In these compounds, infinitely π-stacked redox-active N-methyl bipyridinium cations with near-planar structures are sandwiched by cyanide-bridged MnII–FeIII or ZnII–FeIII layers. Radical–π interactions among the infinitely π-stacked N-methyl bipyridinium components favor the extension of absorption range. Both semiconductors show light/thermo-induced color change with the formation of stable radicals. They have intrinsic photocurrent response in the range of at least 355–2400 nm, which exceeds all reported values for known single-component organic-based semiconductors.
Soft three-dimensional network materials with rational bio-mimetic designs
Authors: Yan Dongjia , Chang Jiahui , Zhang Hang , Liu Jianxing , Song Honglie , Xue Zhaoguo , Zhang Fan , Zhang Yihui 
Published: March 2020

AbstractMany biological tissues offer J-shaped stress–strain responses, since their microstructures exhibit a three-dimensional (3D) network construction of curvy filamentary structures that lead to a bending-to-stretching transition of the deformation mode under an external tension. The development of artificial 3D soft materials and device systems that can reproduce the nonlinear, anisotropic mechanical properties of biological tissues remains challenging. Here we report a class of soft 3D network materials that can offer defect-insensitive, nonlinear mechanical responses closely matched with those of biological tissues. This material system exploits a lattice configuration with different 3D topologies, where 3D helical microstructures that connect the lattice nodes serve as building blocks of the network. By tailoring geometries of helical microstructures or lattice topologies, a wide range of desired anisotropic J-shaped stress–strain curves can be achieved. Demonstrative applications of the developed conducting 3D network materials with bio-mimetic mechanical properties suggest potential uses in flexible bio-integrated devices.
Room-temperature liquid diffused separation induced crystallization for high-quality perovskite single crystals
Authors: Yao Fang , Peng Jiali , Li Ruiming , Li Wenjing , Gui Pengbin , Li Borui , Liu Chang , Tao Chen , Lin Qianqian , Fang Guojia 
Published: March 2020

AbstractLarge single crystals serve as an ideal platform for investigating intrinsic material properties and optoelectronic applications. Here we develop a method, namely, room-temperature liquid diffused separation induced crystallization that uses silicone oil to separate the solvent from the perovskite precursors, to grow high-quality perovskite single crystals. The growth kinetics of perovskite single crystals using this method is elucidated, and their structural and optoelectronic properties are carefully characterized. The resultant perovskite single crystals, taking CH3NH3PbBr3 as an example, exhibit approximately 1 µs lifetime, a low trap density of 4.4 × 109 cm−3, and high yield of 92%, which are appealing for visible light or X-ray detection. We hope our findings will be of great significance for the continued advancement of high-quality perovskite single crystals, through a better understanding of growth mechanisms and their deployment in various optoelectronics. The diffused separation induced crystallization strategy presents a major step forward for advancing the field on perovskite single crystals.
Gene clustering and copy number variation in alkaloid metabolic pathways of opium poppy
Authors: Li Qiushi , Ramasamy Sukanya , Singh Pooja , Hagel Jillian M. , Dunemann Sonja M. , Chen Xue , Chen Rongji , Yu Lisa , Tucker Joseph E. , Facchini Peter J. , Yeaman Sam 
Published: March 2020

AbstractGenes in plant secondary metabolic pathways enable biosynthesis of a range of medically and industrially important compounds, and are often clustered on chromosomes. Here, we study genomic clustering in the benzylisoquinoline alkaloid (BIA) pathway in opium poppy (Papaver somniferum), exploring relationships between gene expression, copy number variation, and metabolite production. We use Hi-C to improve the existing draft genome assembly, yielding chromosome-scale scaffolds that include 35 previously unanchored BIA genes. We find that co-expression of BIA genes increases within clusters and identify candidates with unknown function based on clustering and covariation in expression and alkaloid production. Copy number variation in critical BIA genes correlates with stark differences in alkaloid production, linking noscapine production with an 11-gene deletion, and increased thebaine/decreased morphine production with deletion of a T6ODM cluster. Our results show that the opium poppy genome is still dynamically evolving in ways that contribute to medically and industrially important phenotypes.
Highly enantioselective photo-polymerization enhanced by chiral nanoparticles and in situ photopatterning of chirality
Authors: He Chenlu , Feng Zeyu , Shan Sizhen , Wang Mengqiao , Chen Xin , Zou Gang 
Published: March 2020

AbstractChiral noble metal nanoparticles has recently gained great interest due to their potential applications including ultrasensitive chiral recognition and asymmetric synthesis. We anticipate that they could be utilized to induce asymmetric photo-polymerization reactions with high enantioselectivity and reactivity. Here, we report such a system. By employing silver nanoparticles modified with cysteine as the chiral inducer, polydiacetylene (PDA) with high chiral asymmetry was obtained from achiral diacetylene monomers triggered with unpolarized UV light. Furthermore, the helical sense of chirality can be controlled by varying the wavelength of UV irradiation. This enables a feasible and economical method to fabricate programmable 2D patterns of chiral PDA with tailored chirality distributions, such as smooth gradients in chirality and micropatterns with tailorable circularly polarized luminescence. Our finding not only opens a pathway for producing programmable chiroptical micropatterns, but also is highly valuable for deeper understanding of symmetry breaking in enantioselective photochemical reactions.
The range of non-Kitaev terms and fractional particles in α-RuCl3
Authors: Wang Yiping , Osterhoudt Gavin B. , Tian Yao , Lampen-Kelley Paige , Banerjee Arnab , Goldstein Thomas , Yan Jun , Knolle Johannes , Ji Huiwen , Cava Robert J. , Nasu Joji , Motome Yukitoshi , Nagler Stephen E. , Mandrus David , Burch Kenneth S. 
Published: March 2020

AbstractSignificant efforts have focused on the magnetic excitations of relativistic Mott insulators, predicted to realize the Kitaev quantum spin liquid (QSL). This exactly solvable model involves a highly entangled state resulting from bond-dependent Ising interactions that produce excitations which are non-local in terms of spin flips. A key challenge in real materials is identifying the relative size of the non-Kitaev terms and their role in the emergence or suppression of fractional excitations. Here, we identify the energy and temperature boundaries of non-Kitaev interactions by direct comparison of the Raman susceptibility of α-RuCl3 with quantum Monte Carlo (QMC) results for the Kitaev QSL. Moreover, we further confirm the fractional nature of the magnetic excitations, which is given by creating a pair of fermionic quasiparticles. Interestingly, this fermionic response remains valid in the non-Kitaev range. Our results and focus on the use of the Raman susceptibility provide a stringent new test for future theoretical and experimental studies of QSLs.
Cardiac dysregulation following intrahippocampal kainate-induced status epilepticus
Authors: Levine Amber T. , Born Heather A. , Landstrom Andrew P. , Larson Samuel , Lee Wai Ling , Dao An T. , Wehrens Xander H. , Lai Yi-Chen , Anderson Anne E. 
Published: March 2020

AbstractStatus epilepticus (SE) is a prevalent disorder associated with significant morbidity, including the development of epilepsy and mortality. Cardiac arrhythmias (i.e. inappropriate sinus tachycardia and bradycardia, asystole, and atrioventricular blocks) are observed in patients following SE. We characterized ictal (during a seizure) and interictal (between seizure) cardiac arrhythmogenesis following SE using continuous electrocardiography and video electroencephalography (vEEG) recordings throughout a 14-day monitoring period in an intrahippocampal chemoconvulsant mouse model that develops epilepsy. We quantified heart rhythm abnormalities and examined whether the frequency of cardiac events correlated with epileptiform activity, circadian (light/dark) cycle, the presence of seizures, and survival during this period of early epileptogenesis (the development of epilepsy) following SE. Shortly following SE, mice developed an increased interictal heart rate and heart rhythm abnormalities (i.e. sinus pause and sinus arrhythmias) when compared to control mice. Heart rhythm abnormalities were more frequent during the light cycle and were not correlated with increased epileptiform activity or seizure frequency. Finally, SE animals had early mortality, and a death event captured during vEEG recording demonstrated severe bradycardia prior to death. These cardiac changes occurred within 14 days after SE and may represent an early risk factor for sudden death following SE.
Selective Targeting of Virus Replication by Proton Pump Inhibitors
Authors: Watanabe Susan M. , Ehrlich Lorna S. , Strickland Madeleine , Li Xiaofan , Soloveva Veronica , Goff Arthur J. , Stauft Charles B. , Bhaduri-McIntosh Sumita , Tjandra Nico , Carter Carol 
Published: March 2020

AbstractTwo proton pump inhibitors, tenatoprazole and esomeprazole, were previously shown to inhibit HIV-1 egress by blocking the interaction between Tsg101, a member of the ESCRT-I complex, and ubiquitin. Here, we deepen our understanding of prazole budding inhibition by studying a range of viruses in the presence of tenatoprazole. Furthermore, we investigate the relationship between the chemistry of prodrug activation and HIV-1 inhibition for diverse prazoles currently on the market. We report that tenatoprazole is capable of inhibiting the replication of members of the enveloped filo, alpha, and herpes virus families but not the flavivirus group and not the non-enveloped poliovirus. Another key finding is that prazole prodrugs must be activated inside the cell, while their rate of activation in vitro correlated to their efficacy in cells. Our study lays the groundwork for future efforts to repurpose prazole-based compounds as antivirals that are both broad-spectrum and selective in nature.
Temporal discounting correlates with directed exploration but not with random exploration
Authors: Sadeghiyeh Hashem , Wang Siyu , Alberhasky Maxwell R. , Kyllo Hannah M. , Shenhav Amitai , Wilson Robert C. 
Published: March 2020

AbstractThe explore-exploit dilemma describes the trade off that occurs any time we must choose between exploring unknown options and exploiting options we know well. Implicit in this trade off is how we value future rewards — exploiting is usually better in the short term, but in the longer term the benefits of exploration can be huge. Thus, in theory there should be a tight connection between how much people value future rewards, i.e. how much they discount future rewards relative to immediate rewards, and how likely they are to explore, with less ‘temporal discounting’ associated with more exploration. By measuring individual differences in temporal discounting and correlating them with explore-exploit behavior, we tested whether this theoretical prediction holds in practice. We used the 27-item Delay-Discounting Questionnaire to estimate temporal discounting and the Horizon Task to quantify two strategies of explore-exploit behavior: directed exploration, where information drives exploration by choice, and random exploration, where behavioral variability drives exploration by chance. We find a clear correlation between temporal discounting and directed exploration, with more temporal discounting leading to less directed exploration. Conversely, we find no relationship between temporal discounting and random exploration. Unexpectedly, we find that the relationship with directed exploration appears to be driven by a correlation between temporal discounting and uncertainty seeking at short time horizons, rather than information seeking at long horizons. Taken together our results suggest a nuanced relationship between temporal discounting and explore-exploit behavior that may be mediated by multiple factors.
Lactation stage impacts the glycolytic function of bovine CD4+ T cells during ex vivo activation
Authors: Eder Jordan M. , Gorden Patrick J. , Lippolis John D. , Reinhardt Timothy A. , Sacco Randy E. 
Published: March 2020

AbstractDairy cattle undergo dynamic physiological changes over the course of a full lactation into the dry period, which impacts their immunocompetence. During activation, T cells undergo a characteristic rewiring to increase the uptake of glucose and metabolically reprogram to favor aerobic glycolysis over oxidative phosphorylation. To date it remains to be completely elucidated how the altered energetic demands associated with lactation in dairy cows impacts T cell metabolic reprogramming. Thus, in ourex vivostudies we have examined the influence of stage of lactation (early lactation into the dry period) on cellular metabolism in activated bovine CD4+T cells. Results showed higher rates of glycolytic function in activated CD4+T cells from late lactation and dry cows compared to cells from early and mid-lactation cows. Similarly, protein and mRNA expression of cytokines were higher in CD4+T cells from dry cows than CD4+T cells from lactating cows. The data suggest CD4+T cells from lactating cows have an altered metabolic responsiveness that could impact the immunocompetence of these animals, particularly those in early lactation, and increase their susceptibility to infection.