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Metal‐free, luminescent, carbogenic nanomaterials (LCNMs) constitute a novel class of optical materials with low environmental impact. LCNMs, e.g., carbon dots (CDs), graphitic carbon nitride (g‐C3N4), and carbonized polymer microspheres (CPM) show strong blue/cyan emissions, but rather weak yellow/red emission. This has been a serious drawback in applying them to light‐emitting and bio‐imaging applications. Here, by integrating single‐component LCNMs in photonic microcavities, the study spectroscopically engineers the coupling between photonic modes in these microcavities and optical transitions to "reconfigure" the emission spectra of these luminescent materials. Resonant photons are confined in the microcavity, which allows selective re‐excitation of phosphors to effectively emit down‐converted photons. The down‐converted photons re‐excite the phosphors and are multiply recycled, leading to enhanced yellow/red emissions and resulting in white‐light emission (WLE). Furthermore, by adjusting photonic stop bands of microcavity components, color adaptable (cool, pure, and warm) WLE is flexibly generated, which precisely follows the black‐body Planckian locus in the chromaticity diagram. The proposed approach offers practical low‐cost chromaticity‐adjustable WLE from single‐component, luminescent materials without any chemical or surface modification, or elaborate machinery and processing, paving the way for practical WLE devices. [ABSTRACT FROM AUTHOR]

The association of 2D materials and ferroelectrics offers a promising approach to tune the optoelectronic properties of atomically thin Transition Metal Dichalcogenides (TMDs). In this work, the combined effect of ferroelectricity and light on the optoelectronic properties of monolayer (1L)‐MoS2 deposited on periodically poled lithium niobate crystals is explored. Using scanning micro‐photoluminescence, the effect of excitation intensity, scanning direction, and domain walls on the 1L‐MoS2 photoluminescence properties is analyzed, offering insights into charge modulation of MoS2. The findings unveil a photoinduced charging process dependent on the ferroelectric domain orientation, in which light induces charge generation and transfer at the monolayer‐substrate interface. This highlights the substantial role of light excitation in ferroelectrically‐driven electrostatic doping in MoS2. Additionally, the work provides insights into the effect of the strong, nanometrically confined electric fields on LiNbO3 domain wall surfaces, demonstrating precise control over charge carriers in MoS2, and enabling the creation of deterministic p‐n homojunctions with exceptional precision. The results suggest prospects for novel optoelectronic and photonic application involving monolayer TMDs by combining light‐matter interaction processes and the surface selectivity provided by ferroelectric domain structures. [ABSTRACT FROM AUTHOR]

The current need for coherent light sources for integrated (nano)photonics motivates the search for novel laser designs emitting at technologically relevant wavelengths with high‐frequency stability and low power consumption. Here, a new monolithic architecture that integrates monolayer MoS2 and chains of silver nanoparticles on a rare‐earth (Nd3+) doped LiNbO3 platform is developed to demonstrate Q‐switched lasing operation at the nanoscale. The localized surface plasmons provided by the nanoparticle chains spatially confine the gain generated by Nd3+ ions at subwavelength scales, and large‐area monolayer MoS2 acts as saturable absorber. As a result, an ultra‐compact coherent pulsed light source delivering stable train pulses with repetition rates of hundreds of kHz and pulse duration of 1 µs is demonstrated without the need of any voltage‐driven optical modulation. Moreover, the monolithic integration of the different elements is achieved without sophisticated processing, and it is compatible with LiNbO3‐based photonics. The results highlight the robustness of the approach, which can be extended to other 2D materials and solid‐state gain media. Potential applications in communications, quantum computing, or ultra‐sensitive sensing can benefit from the synergy of the materials involved in this approach, which provides a wealth of opportunities for light control at reduced scales. [ABSTRACT FROM AUTHOR]

The Pb substitution in quantum dots (PQDs) with lesser toxic metals has been widely searched to be environmentally friendly, and be of comparable or improved performance compared to the lead-perovskite. However, the chemical nature of the lead substitute influences the incorporation mechanism into PQDs, which has not been explored in depth. In this work, we analyzed Sr-doping-induced changes in FAPbI3 perovskites by studying the optical, structural properties and chemical environment of FAPb1−xSrxI3 PQDs. The substitution of Pb by 7 at% Sr allows us to achieve FAPb1−xSrxI3 PQDs with 100% PLQY, high stability for 8 months under a relative humidity of 40–50%, and T80 = 6.5 months, one of the highest values reported for halide PQDs under air ambient conditions. FAPb0.93Sr0.07I3 PQDs also exhibit photobrightening under UV illumination for 12 h, recovering 100% PLQY at 15 days after synthesis. The suppression of structural defects mediated by Sr-doping decreases the non-radiative recombination mechanism. By attempting to increase the Sr content in PQDs, a mixture of 2D nanoplatelets/3D nanocubes has emerged, caused by a high Pb deficiency during the FAPb1−xSrxI3 synthesis. This contribution gives a novel insight to understand how the suitable/poor Pb substitution achieved through Sr-doping dictates the photophysical properties of PQDs that may be potentially applicable in optoelectronics. [ABSTRACT FROM AUTHOR]

Background: Our aim is to evaluate the use of laryngeal adductor reflex (LAR) for posterior fossa and brainstem surgeries in conjunction with current intraoperative neuromonitoring (IONM) techniques. Case Description: The patient is a 62-year-old woman who complained of decreased hearing on her left side, dizziness, and left facial palsy. After proper investigation, she was found to have a left vestibular schwannoma. She was scheduled for the left retrosigmoid approach and electrodes embedded on the surface of the endotracheal tube were inserted to monitor for LAR. Preoperative baseline monitoring was recorded. During intraoperative resection of tumor, a significant bilateral amplitude response decrease of the LAR was noted, along with left side decrease in vocal muscle motor evoked potential amplitude responses and bradycardia. Following the LAR event, owed to numerous other IONM changes, surgery was terminated to avoid any complications. Conclusion: LAR is an integral tool to constantly monitor vagus nerve function that can be used in combination with other IONM modalities during lower brainstem and posterior fossa surgeries. We advocate the IONM use of LAR in brainstem surgeries. [ABSTRACT FROM AUTHOR]

In this theoretical work, we study a double quantum dot interacting strongly with a microcavity, while undergoing resonant tunneling. Effects of interdot tunneling on the light-matter hybridized states are determined, and tunability of their brightness degrees, associated dipole moments, and lifetimes is demonstrated. These results predict dipolariton generation in artificial molecules coupled to optical resonators and provide a promising scenario for the control of emission efficiency and coherence times of exciton polaritons. [ABSTRACT FROM AUTHOR]

Background: Control initiatives and continuous surveillance of vector-borne transmission have proved to be effective measures for diminishing the incidence of Chagas disease in endemic countries. However, the active dispersal of infected sylvatic adult triatomines by flight represents one of the main obstacles to eliminating domestic transmission. Methods: In order to determine the risk that active dispersal of sylvatic adult triatomines represents in Colombian northeastern plains, we quantified the distribution and abundance of triatomines in palm trees (primarily Attalea butyracea) using live bait traps. Directional light traps were used to estimate the frequency of sylvatic triatomine dispersal and their possible origin. Finally, the effect of environmental parameters and artificial light sources on the take-off of sylvatic Rhodnius prolixus was evaluated in field experiments. Results: R. prolixus was found in 90 % of the palm trees that densely aggregated toward the northern portion of the study area. R. prolixus, and three other sylvatic triatomine species were found to actively disperse and were attracted to the directional light traps (Triatoma maculata, Panstrongylus geniculatus and Psammolestes arthuri). Temperature, relative humidity, wind speed and night luminosity did not affect the active dispersal of the triatomines which is higher the first two hours after sunset. Artificial lights from houses at 60 and 110 m played a key role in the directionality of the R. prolixus take-offs. Trypanosoma cruzi was isolated from R. prolixus, T. maculata and P. geniculatus and was genotyped as T. cruzi I, III and IV. Conclusions: Our results highlight the potential risk in Colombian northeastern plains of actively dispersing sylvatic triatomines and their role in the domestic introduction of Discrete Typing Units of T. cruzi associated to sylvatic foci of Chagas disease transmission. [ABSTRACT FROM AUTHOR]

The article reviews the book "Geoinformatics in Applied Geomorphology," edited by Siddan Anbazhagan, S. K. Subramanian, and Xiaojun Yang.