Unearthing the Real-Time Excited State Dynamics from Antenna to Rare Earth Ions Using Ultrafast Transient Absorption.

The conventional energy transfer pathway in organic lanthanide complexes is purported to be from the excited singlet state of the chromophore to the triplet state and subsequently directly to the emitting state of the trivalent lanthanide ion. In this work, we found that the energy transfer occurs from the triplet state to the nearest energy level, instead of directly to the emitting state of the lanthanide ion. The triplet decay rate for different lanthanide ions follows an energy gap law from the triplet level to the receiving level of the lanthanide ion.

Highly Efficient Photon Energy Conversion and Ultrasensitive Self-Powered Photodetection via a Monolithic p-3C-SiC Nanothin Film on p-Si/n-Si Double Junction.

The pursuit of increased efficiency of photoelectric energy conversion through optimized semiconductor structures remains highly competitive, with current results yet to align with broad expectations. In this study, we discover a significant enhancement in photocurrent performance of a p-3C-SiC nanothin film on p-Si/n-Si double junction (DJ) heterostructure that integrates p-3C-SiC/p-Si heterojunction and p-Si/n-Si homojunction. The vertical photocurrent (VPC) and vertical photoresponsivity exhibit a substantial enhancement in the DJ heterostructure, surpassing by a maximum of 43-fold compared to the p-3C-SiC/n-Si single junction (SJ) counterpart.

Host Dependency of Boundary between Strong and Weak Crystal Field Strength of Cr Luminescence.

Cr doped near-infrared phosphors hold significant applications and generate considerable research interest. The critical parameter for assessing the strength of the crystal field for Cr in the Tanabe-Sugano diagram is the boundary value of Dq/B, representing the ratio of crystal field splitting to the Racah parameter B. Nevertheless, there are conflicting values for this parameter, as reported in various studies, such as 2.

The effect of wafer thinning and thermal capacitance on chip temperature of SiC Schottky diodes during surge currents.

Due to superior material properties of SiC for high-voltage devices, SiC Schottky diodes are used in energy-conversion systems such as solar-cell inverters, battery chargers, and power modules for electric cars and unmanned aerial vehicles. The reliable operation of these systems requires the chip temperature of SiC Schottky diodes to be maintained within the limit set by the device package. This is especially crucial during surge-current events that dissipate heat within the device.

Comment on "Charge Transfer-Triggered Bi Near-Infrared Emission in YTiO for Dual-Mode Temperature Sensing".

Undoped YTiO exhibits impurity emission bands at low temperatures due to Mn and Cr, as established by codoping with these ions. Contrary to a recent report by Wang et al., , , 36834-36844, we do not observe Bi emission in this codoped host, as also is the case for Fe.

Intraoral and facial rehabilitation retained with zygomatic implants and magnets after complete resection of the maxilla, lip and nose: A clinical report.

Prosthetic rehabilitation is an option available for patients with extensive maxillofacial defects with the ability to restore esthetics and function. The surgical procedure can result in anatomical and functional sequelae leading to functional, psychological and aesthetic disorders. This clinical case report describes the unique and highly-specialized fabrication method of an oral and facial prosthesis for a patient with a near total maxillectomy, excision of upper lip, rhinectomy and radiotherapy for treatment of an extensive malignant neoplasm.

Responsive Regulation of Energy Transfer in Lanthanide-Doped Nanomaterials Dispersed in Chiral Nematic Structure.

The responsive control of energy transfer (ET) plays a key role in the broad applications of lanthanide-doped nanomaterials. Photonic crystals (PCs) are excellent materials for ET regulation. Among the numerous materials that can be used to fabricate PCs, chiral nematic liquid crystals are highly attractive due to their good photoelectric responsiveness and biocompatibility.

Improved Thermal and Chemical Stability of Oxynitride Phosphor from Facile Chemical Synthesis for Vehicle Cornering Lights.

Orange Eu -doped phosphors are essential for light-emitting diodes for cornering lights to prevent fatal road accidents at night, but such phosphors require features of high thermal, chemical stability and facile synthesis. This study reports a series of yellow-orange-red emitting SrAl Si ON :Eu oxynitride phosphors, derived from the SrAlSi N nitride iso-structure by replacing Si -N with Al -O . The introduction of a certain amount of oxygen enabled the facile synthesis under atmospheric pressure using the air-stable raw materials SrCO , Eu O , AlN and Si N .

Integrated microtia and aural atresia management.

Objectives: To present recommendations for the coordinated evaluation and management of the hearing and reconstructive needs of patients with microtia and aural atresia.

Methods: A national working group of 9 experts on microtia and atresia evaluated a working document on the evaluation and treatment of patients. Treatment options for auricular reconstruction and hearing habilitation were reviewed and integrated into a coordinated care timeline.

Energy Transfer Mechanism and Quantitative Modeling of Rate from an Antenna to a Lanthanide Ion.

The excitation energy transfer (ET) pathway and mechanism from an organic antenna to a lanthanide ion has been the subject of discussion for many decades. In the case of europium (Eu), it has been suggested that the transfer originates from the ligand singlet state or a triplet state. Taking the lanthanide complex as an example, we have investigated the spectra and luminescence kinetics, mainly at room temperature and 77 K, to acquire the necessary experimental data.

Thermally Activated Photophysical Processes of Organolanthanide Complexes in Solution.

The effect of temperature upon the lanthanide luminescence lifetime and intensity has been investigated in toluene solution for the complexes (Ln = Eu, Sm, Nd, Yb; Phen = 1,10-phenanthroline; TTA = thenoyltrifluoroacetonate). Thermally excited back-transfer to a charge transfer state was found to occur for Ln = Eu and can be explained by lifetime and intensity back-transfer models. The emission intensity and lifetime were also quenched with increasing temperature for Ln = Sm, and the activation energy for nonradiative decay is similar to that for the thermal population of Sm excited states.

Role of the Rigid Host Structure in Narrow-Band Green Emission of Eu in RbNa(LiSiO): Insights into Electron-Phonon Coupling.

Eu-activated alkali-lithosilicate phosphors exhibit narrow-band emissions that are attractive to high color-rendition and wide color-gamut displays. The microscopic mechanism behind the small emission bandwidth is not presently understood. Here, we report an explicit calculation of the vibronic process occurring in the narrow-band green emission of RbNa[LiSiO]:Eu.

Charging and ultralong phosphorescence of lanthanide facilitated organic complex.

Emission from the triplet state of an organo-lanthanide complex is observed only when the energy transfer to the lanthanide ion is absent. The triplet state lifetime under cryogenic conditions for organo-lanthanide compounds usually ranges up to tens of milliseconds. The compound LaL1(TTA) reported herein exhibits 77 K phosphorescence observable by the naked eye for up to 30 s.

Generation of a Charge Carrier Gradient in a 3C-SiC/Si Heterojunction with Asymmetric Configuration.

It is critical to investigate the charge carrier gradient generation in semiconductor junctions with an asymmetric configuration, which can open a new platform for developing lateral photovoltaic and self-powered devices. This paper reports the generation of a charge carrier gradient in a 3C-SiC/Si heterojunction with an asymmetric electrode configuration. 3C-SiC/Si heterojunction devices with different electrode widths were illuminated by laser beams (wavelengths of 405, 521, and 637 nm) and a halogen bulb.

Orbital transitions: insight into energy transfer through an antenna for an organo-lanthanide complex.

Supported by experimental work, wavefunction theory (WFT) calculations and density functional theory (DFT) calculations employing a range of functionals have been performed for two lanthanide complexes to investigate, in gas and solution phases, the representations of frontier orbitals and the orbital transitions between singlet states. The orbital transitions calculated using CASSCF/NEVTP2 served as reference. Functionals with a higher proportion of Hartree-Fock exchange gave better agreement with WFT.

Complete Genome Sequences of Bacillus cereus Group Phages AaronPhadgers, ALPS, Beyonphe, Bubs, KamFam, OmnioDeoPrimus, Phireball, PPIsBest, YungSlug, and Zainny.

Here, we report genome sequences of 10 Bacillus cereus group-infecting bacteriophages. Each virus was isolated from an environmental sample, contained a double-stranded DNA genome, and belonged to the family. Nine phages exhibit a conserved genome structure, and one phage appears novel in genome structure, sequence, and protein content.

Temperature dependence of the local field effect in YAG:Ce nanocomposites.

The spontaneous emission rate (SER) of a chromophore in a nanoparticle (NP) is determined by the modification of the electric field by its environment. Previous studies of this local field effect have dispersed NPs in non-chemically interacting media of different refractive index (RI) and measured the emission lifetimes. Unfortunately, the applicable solvents cover only a small range of RI so that the test of a theoretical model is limited.

Establishment of an endoscopic retrograde cholangiopancreatography (ERCP) program in rural Kenya: a review of patient and trainee outcomes.

Background: Endoscopic retrograde cholangiopancreatography (ERCP) is a leading modality for treatment of biliary and pancreatic disease but is not widely available in sub-Saharan Africa. We aimed to assess the development and outcomes of an ERCP service in southwestern Kenya, including case volumes, success rates, infrastructure, and training.

Methods: We conducted a retrospective review of all ERCPs performed at Tenwek Hospital in Bomet, Kenya between January 1, 2011 and March 31, 2020.

Prosthetic Facial Reconstruction in a Blast Injury Case.

The management of blast and burn injuries to the facial soft tissue and craniomaxillofacial skeleton has been a challenge since the inception of reconstructive plastic surgery. These injuries continue to present complex reconstructive challenges today. While there have been advancements in free tissue transfer and vascularized composite allotransplantation, prosthetics have been used successfully since antiquity until the present day.

Medical student support for vulnerable patients during COVID-19 - a convergent mixed-methods study.

Background: The coronavirus pandemic has exerted significant impacts on primary care, causing rapid digital transformation, exacerbating social isolation, and disrupting medical student and General Practice [GP] trainee education. Here we report on a medical student telephone initiative set-up by a final year GP trainee (the equivalent of a family medicine resident), which aimed to support patients at high risk and vulnerable to the Coronavirus Disease of 2019 [Covid-19]. In addition, it was hoped the project would mitigate a digital divide, enable proactive anticipatory planning, and provide an active learning environment to compensate for the pandemic's impact on medical education.

A Reversible Rhodamine B Based pH Probe with Large Pseudo-Stokes Shift.

A reversible and sensitive pH probe DPE-Rh operates by Förster resonance energy transfer from 1,2-diphenylethyne (DPE) to Rhodamine B (Rh). In the presence of H , the spirolactam ring of the Rhodamine B unit was opened and this resulted in ca. 1000-fold enhancement of fluorescence intensity with linear change over the pH range of 2.

Importance of Volume Ratio in Photonic Effects of Lanthanide-Doped LaPO Nanocrystals.

Experimental variation of the volume ratio (filling factor: i.e., volume of nanoparticles (NPs) compared with that of medium) of nanocomposite materials with doped lanthanide ions demonstrates that it has a significant affect upon local field effects.

3C-SiC/Si Heterostructure: An Excellent Platform for Position-Sensitive Detectors Based on Photovoltaic Effect.

Single-crystalline silicon carbide (3C-SiC) on the Si substrate has drawn significant attention in recent years due to its low wafer cost and excellent mechanical, chemical, and optoelectronic properties. However, the applications of the structure have primarily been focused on piezoresistive and pressure sensors, bio-microelectromechanical system, and photonics. Herein, we report another promising application of the heterostructure as a laser spot position-sensitive detector (PSD) based on the lateral photovoltaic effect (LPE) under nonuniform optical illuminations at zero-bias conditions.

Energy Transfer between Tb and Eu in LaPO: Pulsed versus Switched-off Continuous Wave Excitation.

The energy transfer (ET) between Tb and Eu is investigated experimentally and with available theoretical models in the regime of high Tb concentrations in ≈30 nm LaPO nanoparticles at room temperature. The ET efficiency approaches 100% even for lightly Eu-doped materials. The major conclusion from the use of pulsed laser excitation and switched-off continuous wave laser diode excitation is that the energy migration between Tb ions, situated on La sites with ≈4 Å separation, is not fast.

Impressive near-infrared brightness and singlet oxygen generation from strategic lanthanide-porphyrin double-decker complexes in aqueous solution.

Although lanthanide double-decker complexes with hetero-macrocyclic ligands as functional luminescent and magnetic materials have promising properties, their inferior water solubility has negated their biomedical applications. Herein, four water-soluble homoleptic lanthanide (  , , and ) sandwiches with diethylene-glycol-disubstituted porphyrins () are reported, with their structures proven by both quantum chemical calculations and scanning tunneling microscopy. Our findings demonstrate that the near-infrared emission intensity and singlet oxygen (O) quantum yields of and in aqueous media are higher than those of the reported capped lanthanide monoporphyrinato analogues, and ; the brightness and luminescence lifetime in water of are greater than those of .