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Versatile interfaces with strong and tunable light-matter interactions are essential for quantum science1 because they enable mapping of quantum properties between light and matter1. Recent studies2-10 have proposed a method of controlling light-matter interactions using the rich interplay of photon-mediated dipole-dipole interactions in structured subwavelength arrays of quantum emitters. However, a key aspect of this approach-the cooperative enhancement of the light-matter coupling strength and the directional mirror reflection of the incoming light using an array of quantum emitters-has not yet been experimentally demonstrated. Here we report the direct observation of the cooperative subradiant response of a two-dimensional square array of atoms in an optical lattice. We observe a spectral narrowing of the collective atomic response well below the quantum-limited decay of individual atoms into free space. Through spatially resolved spectroscopic measurements, we show that the array acts as an efficient mirror formed by a single monolayer of a few hundred atoms. By tuning the atom density in the array and changing the ordering of the particles, we are able to control the cooperative response of the array and elucidate the effect of the interplay of spatial order and dipolar interactions on the collective properties of the ensemble. Bloch oscillations of the atoms outside the array enable us to dynamically control the reflectivity of the atomic mirror. Our work demonstrates efficient optical metamaterial engineering based on structured ensembles of atoms4,8,9 and paves the way towards controlling many-body physics with light5,6,11 and light-matter interfaces at the single-quantum level7,10.
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Owing to its diverse activation processes including single-electron transfer (SET) and hydrogen-atom transfer (HAT), visible-light photocatalysis has emerged as a sustainable and efficient platform for organic synthesis. These processes provide a powerful avenue for the direct functionalization of C(sp3)-H bonds under mild conditions. Over the past decade, there have been remarkable advances in the enantioselective functionalization of the C(sp3)-H bond via photocatalysis combined with conventional asymmetric catalysis. Herein, we summarize the advances in asymmetric C(sp3)-H functionalization involving visible-light photocatalysis and discuss two main pathways in this emerging field: (a) SET-driven carbocation intermediates are followed by stereospecific nucleophile attacks; and (b) photodriven alkyl radical intermediates are further enantioselectively captured by (i) chiral π-SOMOphile reagents, (ii) stereoselective transition-metal complexes, and (iii) another distinct stereoscopic radical species. We aim to summarize key advances in reaction design, catalyst development, and mechanistic understanding, to provide new insights into this rapidly evolving area of research.
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In this work, we unveil a novel, to the best of our knowledge, AI-based design method (AIDN1) specifically developed for photonic crystal resonator designs, capable of handling complex designs with over 10 degrees of freedom (DoFs) and considering practical fabrication uncertainties to minimize the common simulation-to-reality (sim2real) gap. Especially, we introduce an ultrashort (<5 µm) curved nanobeam resonator, which obtains an ultrahigh theoretical quality factor (Q-factor) of 2 × 107 and maintains a theoretical Q-factor above 105 even under high fabrication variations. Importantly, we emphasize that AIDN1 is generalizable and our work serves as a solid foundation for future laser fabrication endeavors beyond the realm of ultrashort 1D photonic crystal (PhC) resonators.
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In computational imaging and lithography, it has been a challenge for a numerical model to faithfully preserve symmetries in the physical imaging system. In this Letter, we present a project-to-symmetry-subspace (PTSS) method to prevent symmetry loss during the iterative generation of optical kernels. Essentially, PTSS is to project iterative vectors onto a predefined symmetric subspace when decomposing the transmission cross coefficient (TCC). Simulation results demonstrate the PTSS-generation of a truncated set of optical kernels that are substantially free of symmetry error, regardless of the order of truncation.
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OBJECTIVES: Hypertrophic cardiomyopathy is the leading cause of sudden cardiac death among the paediatric population. The aim of this study is to investigate the prevalence and clinical significance of late gadolinium enhancement, as assessed by cardiac MRI, in paediatric hypertrophic cardiomyopathy. METHODS: A systematic literature search was conducted in PubMed, SCOPUS, and Ovid SP to identify relevant studies. Pooled estimates with a 95% confidence interval were calculated using the random-effects generic inverse variance model. Statistical analysis was performed using Review Manager v5.4 and R programming. RESULTS: Seventeen studies were included in this meta-analysis, encompassing a total of 778 patients. Late gadolinium enhancement was highly prevalent in paediatric hypertrophic cardiomyopathy, with a pooled prevalence of 51% (95% confidence interval, 40-62%). The estimated extent of focal fibrosis expressed as a percentage of left ventricular mass was 4.70% (95% confidence interval, 2.11-7.30%). The presence of late gadolinium enhancement was associated with an increased risk of adverse cardiac events (pooled odds ratio 3.49, 95% confidence interval 1.10-11.09). The left ventricular mass index of late gadolinium enhancement-positive group was higher than the negative group, with a standardised mean difference of 0.91 (95% confidence interval, 0.42-1.41). CONCLUSION: This meta-analysis demonstrates that prevalence of late gadolinium enhancement in paediatric hypertrophic cardiomyopathy is similar to that in the adult population. The presence and extent of late gadolinium enhancement are independent predictors of adverse cardiac events, underscoring their prognostic significance among the paediatric population.
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Herein we present a novel protocol to access α-functionalized saturated aza-heterocycles, and a variety of nucleophilic groups, such as indole, naphthol, phenol, pyrrole, furyl, nitromethyl, and cyano, could be easily installed into saturated aza-heterocycles. Furthermore, a range of biologically valuable 3,3'-diindolylmethane derivatives could also be readily accessed under mild photocatalytic conditions.
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Private equity acquisitions are increasing among orthopedic practices. The concepts and vocabulary surrounding these deals may be foreign to physicians. There are both potential risks and potential benefits to physicians at the center of these complex deals, and a clear understanding of any proposed private equity acquisition is crucial. Short-term data on private equity acquisition in other procedure-based outpatient specialties have shown that private equity ownership consistently increased the number of patients seen per provider, allowed amount per claim, and utilization of advanced practice practitioners. These studies did not show consistent changes in the rates of invasive procedures or negative impacts on patient care. Each practice will need to carefully consider any potential private equity involvements.
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Measurement-based quantum computing relies on the rapid creation of large-scale entanglement in a register of stable qubits. Atomic arrays are well suited to store quantum information, and entanglement can be created using highly-excited Rydberg states. Typically, isolating pairs during gate operation is difficult because Rydberg interactions feature long tails at large distances. Here, we engineer distance-selective interactions that are strongly peaked in distance through off-resonant laser coupling of molecular potentials between Rydberg atom pairs. Employing quantum gas microscopy, we verify the dressed interactions by observing correlated phase evolution using many-body Ramsey interferometry. We identify atom loss and coupling to continuum modes as a limitation of our present scheme and outline paths to mitigate these effects, paving the way towards the creation of large-scale entanglement.
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Cytomegalovirus (CMV) is the most common cause of congenital infection, affecting 1% of all live births. Intrauterine infection such as CMV infection is a risk factor for developing cerebral palsy. This study aims to investigate the association between congenital CMV infection and the development of cerebral palsy. A systematic literature search was conducted in PubMed, Web of Science and Ovid SP to identify relevant studies. The quality of studies was assessed using the Newcastle-Ottawa Scale. The random-effect model was used to calculate the pooled prevalence. The generic inverse variance method was used for statistical analysis. A total of 12 studies were included in this systematic review and meta-analysis. The overall pooled prevalence of cerebral palsy among patients diagnosed with congenital CMV infection was 26% (95% confidence interval (CI), 13-40%). The overall pooled prevalence of congenital CMV infection among patients with cerebral palsy was 10.9% (95% CI, 5-16%). Congenital CMV infection was significantly associated with the development of cerebral palsy in children. Routine follow-ups should be offered to screen for cerebral palsy.
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Parálisis Cerebral , Infecciones por Citomegalovirus , Niño , Humanos , Parálisis Cerebral/etiología , Parálisis Cerebral/complicaciones , Infecciones por Citomegalovirus/complicaciones , Infecciones por Citomegalovirus/epidemiología , Infecciones por Citomegalovirus/diagnóstico , Citomegalovirus , Factores de Riesgo , PrevalenciaRESUMEN
The selective oxidation of aniline to metastable and valuable azoxybenzene, azobenzene or nitrosobenzene has important practical significance in organic synthesis. However, uncontrollable selectivity and laborious synthesis of the expensive required catalysts severely hinders the uptake of these reactions in industrial settings. Herein, we have pioneered the discovery of Zr(OH)4 as an efficient heterogeneous catalyst capable of the selective oxidation of aniline, using either peroxide or O2 as oxidant, to selectively obtain various azoxybenzenes, symmetric/unsymmetric azobenzenes, as well as nitrosobenzenes, by simply regulating the reaction solvent, without the need for additives. Mechanistic experiments and DFT calculations demonstrate that the activation of H2 O2 and O2 is primarily achieved by the bridging hydroxyl and terminal hydroxyl groups of Zr(OH)4 , respectively. The present work provides an economical and environmentally friendly strategy for the selective oxidation of aniline in industrial applications.
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Grain boundary management is critical to the performance and stability of polycrystalline perovskite solar cells (PSCs), especially large-area devices. However, typical passivators are insulating in nature and limit carrier transport. Here, we design a supramolecular binder for grain boundaries to simultaneously passivate defects and promote hole transport across perovskite grain boundaries. By doping the monoamine porphyrins (MPs, M = Co, Ni, Cu, Zn, or H) into perovskite films, MPs self-assemble into supramolecules at grain boundaries. Organic cations in perovskites protonate MPs in supramolecules to form ammonium porphyrins bound on the perovskite grain surface, to passivate defects and extract holes from the perovskite lattice. Periodic polarons in supramolecules (especially NiP-supramolecule) promote the transport of extracted holes across boundaries, reducing nonradiative carrier recombination. The NiP-doped PSCs reveal a certified efficiency of 22.1% for an active area of 1.0 cm2 with the remarkably improved open-circuit voltage and fill factor. The unencapsulated device retained over 80% initial performance under AM 1.5G solar light continuous illumination or heating at 85 °C over 3000 h.
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INTRODUCTION/AIMS: We studied a patient with a congenital myasthenic syndrome (CMS) caused by a dominant mutation in the synaptotagmin 2 gene (SYT2) and compared the clinical features of this patient with those of a previously described patient with a recessive mutation in the same gene. METHODS: We performed electrodiagnostic (EDX) studies, genetic studies, muscle biopsy, microelectrode recordings and electron microscopy (EM). RESULTS: Both patients presented with muscle weakness and bulbar deficits, which were worse in the recessive form. EDX studies showed presynaptic failure, which was more prominent in the recessive form. Microelectrode studies in the dominant form showed a marked reduction of the quantal content, which increased linearly with higher frequencies of nerve stimulation. The MEPP frequencies were normal at rest but increased markedly with higher frequencies of nerve stimulation. The EM demonstrated overdeveloped postsynaptic folding, and abundant endosomes, multivesicular bodies and degenerative lamellar bodies inside small nerve terminals. DISCUSSION: The recessive form of CMS caused by a SYT2 mutation showed far more severe clinical manifestations than the dominant form. The pathogenesis of the dominant form likely involves a dominant-negative effect due to disruption of the dual function of synaptotagmin as a Ca2+ -sensor and modulator of synaptic vesicle exocytosis.
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Mutación/genética , Síndromes Miasténicos Congénitos/genética , Unión Neuromuscular/genética , Sinaptotagmina II/genética , Adulto , Preescolar , Femenino , Humanos , Síndrome Miasténico de Lambert-Eaton/genética , Síndrome Miasténico de Lambert-Eaton/fisiopatología , Masculino , Debilidad Muscular/genética , Debilidad Muscular/fisiopatología , Síndromes Miasténicos Congénitos/diagnóstico , Unión Neuromuscular/fisiopatologíaRESUMEN
BACKGROUND: Subjective cognitive decline may represent at-risk persons progressing to mild cognitive impairment (MCI), which can be exacerbated by effects of anesthesia and surgery. The objective of this systematic review is to identify the most common questions in subjective cognitive complaint and informant-reported questionnaires used in assessing cognitive impairment of elderly patients that are correlated with standardized tests for cognitive impairment screening. METHODS: We searched Medline, PubMed, Embase, Cochrane Central Register of Controlled Trials, Cochrane Database, Emcare Nursing, Web of Science, Scopus, CINAHL, ClinicalTrials.Gov, and ICTRP between September 20, 2005 to August 31, 2020. We included studies that evaluated subjective cognitive complaints and informant-reported questions in elderly patients. RESULTS AND CONCLUSION: A total of 28,407 patients were included from 22 studies that assessed 21 subjective complaint questionnaires and nine informant-reported questionnaires. The most common subjective cognitive complaints were those assessing anterograde memory, closely followed by perceptual-motor function and executive function. The most common informant-reported questions were those assessing executive function, temporal orientation, and anterograde memory. Questions assessing learning and memory were most associated with results from standardized tests assessing cognitive impairment. Assessing learning and memory plays a key role in evaluating subjective cognitive decline in elderly patients. Delivering subjective cognitive complaints questions to elderly patient preoperatively may aid in screening for those exhibiting cognitive signs, and in turn are at risk of postoperative complications. Thus, the results from this review contribute to knowledge for healthcare professionals regarding the use of subjective cognitive complaints and informant-reported complaints in preoperative settings.
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Disfunción Cognitiva/diagnóstico , Tamizaje Masivo/métodos , Complicaciones Posoperatorias/epidemiología , Anciano , Humanos , Aprendizaje/fisiología , Memoria/fisiología , Pruebas Neuropsicológicas , Cuidados Preoperatorios/métodos , Factores de Riesgo , Encuestas y CuestionariosRESUMEN
BACKGROUND: Minimally invasive liver resection (MILR) has gained momentum in recent years. This study of contemporary data compares economic and clinical outcomes between MILR and open liver resection (OLR). METHODS: We extracted data for patients undergoing liver resection between October 2015-September 2018 from the Premier Healthcare Database. We conducted a propensity score matched analysis to compare complications, in-hospital mortality, inpatient readmissions, discharge to institutional post-acute care, operating room time (ORT), length of stay (LOS), and total hospital cost between MILR and OLR patients. RESULTS: From the eligible OLR (n = 3349) and MILR (n = 1367) patients, we propensity score matched 1261 from each cohort at a 1:1 ratio. After matching, MILR was associated with lower rates of complications (bleeding: 8.2% vs. 17.4%; respiratory failure: 5.5% vs. 10.9%; intestinal obstruction: 3.6% vs. 6.0%, and pleural effusion: 1.9% vs. 4.9%), in-hospital mortality (0.5% vs. 3.0%), 90-day inpatient readmissions (10.4% vs. 14.3%), discharge to institutional post-acute care (6.9% vs. 12.3%), shorter ORT (257 vs. 308 min) and LOS (4.3 vs. 7.2 days), and lower hospital costs ($19463 vs. $29119) (all P < 0.001). CONCLUSION: MILR was associated with lower risk of complications and reduced hospital resource utilizations as compared with OLR.
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Carcinoma Hepatocelular , Laparoscopía , Neoplasias Hepáticas , Carcinoma Hepatocelular/cirugía , Hepatectomía/efectos adversos , Humanos , Tiempo de Internación , Neoplasias Hepáticas/cirugía , Complicaciones Posoperatorias/etiología , Puntaje de Propensión , Estudios RetrospectivosRESUMEN
Light-driven synthesis of plasmonic metal nanostructures has garnered broad scientific interests. Although it has been widely accepted that surface plasmon resonance (SPR)-generated energetic electrons play an essential role in this photochemical process, the exact function of plasmon-generated hot holes in regulating the morphology of nanostructures has not been fully explored. Herein, we discover that those hot holes work with surface adsorbates collectively to control the anisotropic growth of gold (Au) nanostructures. Specifically, it is found that hot holes stabilized by surface adsorbed iodide enable the site-selective oxidative etching of Au0, which leads to nonuniform growths along different lateral directions to form six-pointed Au nanostars. Our studies establish a molecular-level understanding of the mechanism behind the plasmon-driven synthesis of Au nanostars and illustrate the importance of cooperation between charge carriers and surface adsorbates in regulating the morphology evolution of plasmonic nanostructures.
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The metal/oxide interface has been extensively studied due to its importance for heterogeneous catalysis. However, the exact role of interfacial atomic structures in governing catalytic processes still remains elusive. Herein, we demonstrate how the manipulation of atomic structures at the Au/TiO2 interface significantly alters the interfacial electron distribution and prompts O2 activation. It is discovered that at the defect-free Au/TiO2 interface electrons transfer from Ti3+ species into Au nanoparticles (NPs) and further migrate into adsorbed perimeter O2 molecules (i.e., in the form of Au-O-O-Ti), facilitating O2 activation and leading to a ca. 34 times higher CO oxidation activity than that on the oxygen vacancy (Vo)-rich Au/TiO2 interface, at which electrons from Ti3+ species are trapped by interfacial Vo on TiO2 and hardly interact with perimeter O2 molecules. We further reveal that the calcination releases those trapped electrons from interfacial Vo to facilitate O2 activation. Collectively, our results establish an atomic-level description of the underlying mechanism regulating metal/oxide interfaces for the optimization of heterogeneous catalysis.
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Three-dimensional (3D) molecular imaging of biological structures is important for a wide range of research. In recent decades, secondary-ion mass spectrometry (SIMS) has been recognized as a powerful technique for both two-dimensional and 3D molecular imaging. Sample fixations (e.g., chemical fixation and cryogenic fixation methods) are necessary to adapt biological samples to the vacuum condition in the SIMS chamber, which has been demonstrated to be nontrivial and less controllable, thus limiting the wider application of SIMS on 3D molecular analysis of biological samples. Our group recently developed in situ liquid SIMS that offers great opportunities for the molecular study of various liquids and liquid interfaces. In this work, we demonstrate that a further development of the vacuum-compatible microfluidic device used in in situ liquid SIMS provides a convenient freeze-fixation of biological samples and leads to more controllable and convenient 3D molecular imaging. The special design of this new vacuum-compatible liquid chamber allows an easy determination of sputter rates of ice, which is critical for calibrating the depth scale of frozen biological samples. Sputter yield of a 20 keV Ar1800+ ion on ice has been determined as 1500 (±8%) water molecules per Ar1800+ ion, consistent with our results from molecular dynamics simulations. Moreover, using the information of ice sputter yield, we successfully conduct 3D molecular imaging of frozen homogenized milk and observe network structures of interesting organic and inorganic species. Taken together, our results will significantly benefit various research fields relying on 3D molecular imaging of biological structures.
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Imagenología Tridimensional/métodos , Dispositivos Laboratorio en un Chip , Espectrometría de Masa de Ion Secundario , Animales , Congelación , Imagenología Tridimensional/instrumentación , Iones/química , Leche/química , Vacio , Agua/químicaRESUMEN
Genetic polymorphisms have been shown to affect opioid requirement for pain relief. However, true genetic effect is often difficult to assess due to underlying pain conditions and placebo effects. The goal of this study was to understand how common polymorphisms affect opioid effects while controlling for these factors. A randomized, double-blind, placebo-controlled study was implemented to assess how opioid effects are modulated by COMT (rs6269, rs4633, rs4848, rs4680), OPRM1 (A118G), and OPRK1 (rs1051660, rs702764, rs16918875). One hundred and eight healthy subjects underwent experimental pain testing before and after morphine, butorphanol, and placebo (saline). Association analysis was performed between polymorphisms/haplotypes and opioid response, while correcting for race, gender, placebo effects, and multiple comparisons. Pressure pain was significantly associated with rs6269 and rs4633 following butorphanol. The AA genotype of rs4680 or A_T_C_A/ A_T_C_A (rs6269_rs4633_ rs4818_rs4680) diplotype of COMT, combined with the AG genotype of OPRM1 A118G, showed significantly increased pressure pain threshold from butorphanol. Opioid effects on pressure, ischemic, heat pain, and side effects were nominally associated with several SNPs and haplotypes. Effects were often present in one opioid but not the other. This indicates that these polymorphisms affect pain relief from opioids, and that their effects are opioid and pain modality specific.
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Analgésicos Opioides/uso terapéutico , Catecol O-Metiltransferasa/genética , Dolor/genética , Polimorfismo de Nucleótido Simple/genética , Receptores Opioides kappa/genética , Receptores Opioides mu/genética , Adulto , Analgésicos Opioides/farmacología , Método Doble Ciego , Femenino , Humanos , Masculino , Dolor/tratamiento farmacológico , Dimensión del Dolor/efectos de los fármacos , Dimensión del Dolor/métodos , Resultado del Tratamiento , Adulto JovenRESUMEN
Visible-light-driven photochemistry has continued to attract heightened interest due to its capacity to efficiently harvest solar energy and its potential to solve the global energy crisis. Plasmonic nanostructures boast broadly tunable optical properties coupled with catalytically active surfaces that offer a unique opportunity for solar photochemistry. Resonant optical excitation of surface plasmons produces energetic hot electrons that can be collected to facilitate chemical reactions. This review sums up recent theoretical and experimental approaches for understanding the underlying photophysical processes in hot electron generation and discusses various electron-transfer models on both plasmonic metal nanostructures and plasmonic metal/semiconductor heterostructures. Following that are highlights of recent examples of plasmon-driven hot electron photochemical reactions within the context of both cases. The review concludes with a discussion about the remaining challenges in the field and future opportunities for addressing the low reaction efficiencies in hot-electron-induced photochemistry.
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BACKGROUND: We used a population-based database to: (1) compare clinical and economic outcomes between minimally invasive surgery (MIS) and open surgery (OS) for colectomy; and (2) evaluate contemporary trends in MIS rates. METHODS: Retrospective Premier Healthcare Database review of patients undergoing elective inpatient colectomy between January 1, 2010 and September 30, 2017 (first = index admission). Patients were classified into MIS (laparoscopic/robotic) or OS groups, and by left or right colectomy. Propensity score matching (1:1 ratio) of MIS and OS groups was used to address potential confounding from patient/hospital/provider characteristics. Study outcomes, measured during index admission, included major perioperative complications [anastomotic leak (AL), bleeding, infection, and a composite of infection/AL], operating room time (ORT), length of stay (LOS), and total hospital costs. RESULTS: Among 134,970 study-eligible patients, MIS rates increased from ~ 2% (2010) to 19-23% (2017), driven by a > tenfold increase in robotic surgery. The matched MIS and OS colectomy groups comprised 46,708 (left) and 44,560 (right) total patients. Risks of AL, bleeding, and infection were lower for MIS versus OS (all p < 0.001). In left: AL occurred in 7.9% of MIS versus 9.9% of OS; bleeding 7.8% versus 9.7%; infection 3.3% versus 5.8%; infection/AL 9.8% versus 13.3%. In right: AL 8.9% versus 11.1%; bleeding 9.8% versus 10.8%; infection 3.0% versus 5.1%; infection/AL 10.5% versus 10.4%. Although ORTs were longer with MIS (left: 240.8 vs. 216.2 min; right: 192.8 vs. 178.0 min), LOS was shorter (left: 5.4 vs. 7.1 days; right: 5.5 vs. 7.1 days), and total hospital costs were lower (left: $18,564 vs. $19,960; right: $17,375 vs. $19,417) versus OS (all p < 0.001). CONCLUSIONS: Compared with OS, MIS was associated with significantly lower risk of major perioperative complications (including AL), lower LOS, and lower total hospital costs, despite longer OR times. MIS colectomy rates have increased over time; recent gains appear to be due to uptake of robotic surgery.