The scanning tunnelling microscope (STM) may be used as a low-energy, electrical nanosource of surface plasmon polaritons and light. In this article, we demonstrate that the optimum mode of operation of the STM for maximum photon emission is completely different in air than in vacuum. To this end, we investigate the emission of photons, the variation in the relative tip-sample distance and the measured current as a function of time for an STM operating in air. Contrary to the case of an STM operating in vacuum, the measured current between the tip and sample for an STM in air is very unstable (rapidly fluctuating in time) when the applied voltage between the tip and sample is in the ∼1.5-3 V range (i.e., in the energy range of visible photons). The photon emission occurs in short (50 μs) bursts when the STM tip is closest to the sample. The current instabilities are shown to be a key ingredient for producing intense light emission from an STM operating in air (photon emission rate several orders of magnitude higher than for stable current). These results are explained in terms of the interplay between the tunnel current and the electrochemical current in the ubiquitous thin water layer that exists when working in air.
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http://dx.doi.org/10.1088/0957-4484/27/46/465201 | DOI Listing |
ACS Nano
January 2025
Department of Orthopaedics, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, P.R. China.
Deer antler blastema progenitor cells (ABPCs) are promising for regenerative medicine due to their role in annual antler regeneration, the only case of complete organ regeneration in mammals. ABPC-derived signals show great potential for promoting regeneration in tissues with limited natural regenerative ability. Our findings demonstrate the capability of extracellular vesicles from ABPCs (EVs) to repair spinal cord injury (SCI), a condition with low regenerative capacity.
View Article and Find Full Text PDFPLoS One
January 2025
Department of Competence Center for Renewable Energies and Energy Efficiency, Hamburg University of Applied Sciences, Hamburg, Germany.
With the increasing height and rotor diameter of wind turbines, bat activity monitoring within the risk area becomes more challenging. This study investigates the impact of Unmanned Aerial Systems (UAS) on bat activity and explores acoustic bat detection via UAS as a new data collection method in the vicinity of wind turbines. We tested two types of UAS, a multicopter and a Lighter Than Air (LTA) UAS, to understand how they may affect acoustically recorded and analyzed bat activity level for three echolocation groups: Pipistrelloid, Myotini, and Nyctaloid.
View Article and Find Full Text PDFMil Med
January 2025
Department of the Air Force Exercise Science Unit, JBSA-Randolph, TX 78150, USA.
Introduction: Physical fitness is an integral part of military readiness, and failure to meet military Physical Fitness Assessment (PFA) standards can severely damage or end careers. Postpartum active duty service members experience a drop in PFA scores and passing rates compared to their pre-pregnancy assessments. Each branch recently extended recovery time to 12 months, but more research is required to see if this change alone is enough to return both active duty and reserve component postpartum personnel to their own preconception PFA outcomes (scores, passing rates, and injury rates) and those of a control group of nullpartum female airmen.
View Article and Find Full Text PDFCardiovasc Toxicol
January 2025
Department of Physiology, Pharmacology and Toxicology, West Virginia University School of Medicine, Morgantown, WV, USA.
Pregnancy is a vulnerable time with significant cardiovascular changes that can lead to adverse outcomes, which can extend into the postpartum window. Exposure to emissions from electronic cigarettes (Ecig), commonly known as "vaping," has an adverse impact on cardiovascular function during pregnancy and post-natal life of offspring, but the postpartum effects on maternal health are poorly understood. We used a Sprague Dawley rat model, where pregnant dams are exposed to Ecigs between gestational day (GD)2-GD21 to examine postpartum consequences.
View Article and Find Full Text PDFEur Spine J
January 2025
Department of Orthopedic, MacKay Memorial Hospital, No. 92, Sec. 2, Zhongshan N. Rd, Taipei, Taiwan.
Purpose: Spine surgery, particularly deformity correction, is associated with a high risk of peri-operative or post-operative complications, and these complications can lead to catastrophic consequences. This case report will present the etiology and treatment process of the peri-operative cardiac arrest during scoliosis correction surgery.
Method: In this report, we present a case of cardiac arrest during posterior correction surgery in a 17-year-old female patient with adolescent idiopathic scoliosis.
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