84 research outputs found
Bis[4-oxido-2-oxo-2,3-dihydropyrimidin-1-ium-5-carboxylato(1.5−)-κ2 O 4,O 5]bis(1,10-phenanthroline-κ2 N,N′)dysprosium(III) dihydrate
In the title compound, [Dy(C5H2.5N2O4)2(C12H8N2)2]·2H2O, the DyIII ion is located on a twofold rotation axis and is coordinated in a square-antiprismatic geometry by two chelating 1,10-phenanthroline molecules as well as two 4-oxido-2-oxo-2,3-dihydropyrimidin-1-ium-5-carboxylato(1.5−) anions. N—H⋯O and O—H⋯O hydrogen bonds help to stabilize the crystal structure. The H atom involved in an N—H⋯N hydrogen bond is disordered around a twofold rotation axis
N-(1H-1,2,4-Triazol-5-yl)pyridine-2-carboxamide
In the structure of the title compound, C8H7N5O, the pyridine ring and the imidazole ring are nearly coplanar, making a dihedral angle of 2.97 (15)°. An intramolecular N—H⋯O hydrogen bond occurs. In the crystal molecules are connected by intermolecular hydrogen bonds and π–π stacking interactions between neighboring imidazole rings [centroid–centroid distance = 3.5842 (5) Å and off-set angle = 21.77°], leading to the formation of a two-dimensional supramolecular sheet
4,4′-Bipyridinium 1,4-phenylenediacetate
The title compound, C10H10N2
2+·C10H8O4
2−, has inversion centres located at the geometric centres of the 1,4-phenylenediacetate anion and 4,4′-bipyridinium cation. The anions and cations are connected by N—H⋯O hydrogen bonds, forming one-dimensional supramolecular chains, which interact with each other via π–π interactions [centroid–centroid distance = 3.938 (2) Å], building a two-dimensional supramolecular sheet
Strong Photoluminescence Enhancement of MoS2 through Defect Engineering and Oxygen Bonding
We report on a strong photoluminescence (PL) enhancement of monolayer MoS2
through defect engineering and oxygen bonding. Micro- PL and Raman images
clearly reveal that the PL enhancement occurs at cracks/defects formed during
high temperature vacuum annealing. The PL enhancement at crack/defect sites
could be as high as thousands of times after considering the laser spot size.
The main reasons of such huge PL enhancement include: (1) the oxygen chemical
adsorption induced heavy p doping and the conversion from trion to exciton; (2)
the suppression of non-radiative recombination of excitons at defect sites as
verified by low temperature PL measurements. First principle calculations
reveal a strong binding energy of ~2.395 eV for oxygen molecule adsorbed on an
S vacancy of MoS2. The chemical adsorbed oxygen also provides a much more
effective charge transfer (0.997 electrons per O2) compared to physical
adsorbed oxygen on ideal MoS2 surface. We also demonstrate that the defect
engineering and oxygen bonding could be easily realized by oxygen plasma
irradiation. X-ray photoelectron spectroscopy further confirms the formation of
Mo-O bonding. Our results provide a new route for modulating the optical
properties of two dimensional semiconductors. The strong and stable PL from
defects sites of MoS2 may have promising applications in optoelectronic
devices.Comment: 23 pages, 9 figures, to appear in ACS Nan
Explain-then-Translate: An Analysis on Improving Program Translation with Self-generated Explanations
This work explores the use of self-generated natural language explanations as
an intermediate step for code-to-code translation with language models. Across
three types of explanations and 19 programming languages constructed from the
MultiPL-E dataset, we find the explanations to be particularly effective in the
zero-shot case, improving performance by 12% on average. Improvements with
natural language explanations are particularly pronounced on difficult
programs. We release our dataset, code, and canonical solutions in all 19
languages.Comment: 9 pages, 4 figures, 5 tables, 48 pages total. To be published in
EMNLP Findings 202
Association between angiotensin-converting enzyme inhibitor-induced cough and the risk of lung cancer: a Mendelian randomization study
Background: Observational studies and meta-analyses have demonstrated a positive correlation between the use of angiotensin-converting enzyme inhibitors (ACEIs) and lung cancer. However, the findings remain controversial; furthermore, the relationship between ACEI-induced cough and lung cancer development remains unknown. We used Mendelian randomization (MR) to verify the association between ACEI use, ACEI-induced cough, and the risk of lung cancer.Methods: We performed a two-sample MR analysis to determine the unconfounded relationships between ACE inhibition, which mimics the effects of ACEIs, and genetic proxies for ACEI-induced cough and lung cancer. Single nucleotide polymorphisms that imitate ACE receptors and ACEI-induced cough were collected and integrated into a meta-analysis of existing genome-wide association studies for various lung cancers. The relationship was quantified using inverse variance weighting, weighted median, and MR-Egger methods.Results: A statistically significant association was observed between ACE inhibition and the risk of small cell lung cancer for Europeans (excluding rs118121655/rs80311894). Associations were identified between ACEI-induced cough and the risk of lung cancer for Europeans, although not for Asians, and between ACEI-induced cough and lung adenocarcinoma (excluding rs360206).Conclusion: Our findings reveal a relationship between ACE inhibition and lung cancer development, as well as a significant association between ACEI-induced cough and a higher risk of lung cancer for Europeans. Patients with hypertension who experience dry cough as a side effect of ACEI use should consider switching to an alternative antihypertensive treatment
DIP-2 suppresses ectopic neurite sprouting and axonal regeneration in mature neurons.
Neuronal morphology and circuitry established during early development must often be maintained over the entirety of animal lifespans. Compared with neuronal development, the mechanisms that maintain mature neuronal structures and architecture are little understood. The conserved disco-interacting protein 2 (DIP2) consists of a DMAP1-binding domain and two adenylate-forming domains (AFDs). We show that the Caenorhabditis elegans DIP-2 maintains morphology of mature neurons. dip-2 loss-of-function mutants display a progressive increase in ectopic neurite sprouting and branching during late larval and adult life. In adults, dip-2 also inhibits initial stages of axon regeneration cell autonomously and acts in parallel to DLK-1 MAP kinase and EFA-6 pathways. The function of DIP-2 in maintenance of neuron morphology and in axon regrowth requires its AFD domains and is independent of its DMAP1-binding domain. Our findings reveal a new conserved regulator of neuronal morphology maintenance and axon regrowth after injury
Applications of lasers: A promising route toward low-cost fabrication of high-efficiency full-color micro-LED displays
Micro-light-emitting diodes (micro-LEDs) with outstanding performance are promising candidates for next-generation displays. To achieve the application of high-resolution displays such as meta-displays, virtual reality, and wearable electronics, the size of LEDs must be reduced to the micro-scale. Thus, traditional technology cannot meet the demand during the processing of micro-LEDs. Recently, lasers with short-duration pulses have attracted attention because of their unique advantages during micro-LED processing such as noncontact processing, adjustable energy and speed of the laser beam, no cutting force acting on the devices, high efficiency, and low cost. Herein, we review the techniques and principles of laser-based technologies for micro-LED displays, including chip dicing, geometry shaping, annealing, laser-assisted bonding, laser lift-off, defect detection, laser repair, mass transfer, and optimization of quantum dot color conversion films. Moreover, the future prospects and challenges of laser-based techniques for micro-LED displays are discussed
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