The main purpose of this work is to thoroughly describe the implementation protocol of laser-induced breakdown spectroscopy (LIBS) method in the plant analysis. Numerous feasibility studies and recent progress in instrumentation and trends in chemical analysis make LIBS an established method in plant bioimaging. In this work, we present an easy and straightforward phytotoxicity case study with a focus on LIBS method. We intend to demonstrate in detail how to manipulate with plants after exposures and how to prepare them for analyses. Moreover, we aim to achieve 2D maps of spatial element distribution with a good resolution without any loss of sensitivity. The benefits of rapid, low-cost bioimaging are highlighted. In this study, cabbage (Brassica oleracea L.) was treated with an aqueous dispersion of photon-upconversion nanoparticles (NaYF4 doped with Yb3+ and Tm3+ coated with carboxylated silica shell) in a hydroponic short-term toxicity test. After a 72-hour plant exposure, several macroscopic toxicity end-points were monitored. The translocation of Y, Yb, and Tm across the whole plant was set by employing LIBS with a lateral resolution 100 µm. The LIBS maps of rare-earth elements in B.oleracea plant grown with 50 μg/mL nanoparticle-treated and ion-treated exposures showed the root as the main storage, while the transfer via stem into leaves was minimal. On the contrary, the LIBS maps of plants exposed to the 500 μg/mL nanoparticle-treated and ion-treated uncover slightly different trends, nanoparticles as well as ions were transferred through the stem into leaves. However, the main storage organ was a root as well.

To report the first case series of ureterorenoscopy in North America using the High Power Super Pulse Thulium Fiber Laser for the treatment of upper urinary tract stones.
After Institutional Review Board approval, a multicentric retrospective chart review of patients treated with the High Power Super Pulse Thulium Fiber Laser from October 2019 to March 2020 was conducted. Basic demographic information, pre-operative, and peri-operative data were recorded.
Seventy-six patients were included with a mean age of 60.9 ± 13.3 years. 118 stones were treated including 32 within the ureter, 49 in the lower pole, 37 in mid or upper poles. Dusting technique was commonly used (67.1%) with pulse frequencies up to 2400 Hz. Mean operative time was 59.4 ± 31.5 minutes. Mean laser time and total laser energy were 10.8 ± 14.1 minutes and 12.5 ± 19.1 KJ, respectively. Intraoperative complications were limited to 7 grade 1, 3 grade 2, and 1 grade 3 ureteral injuries and one case of renal collecting system bleeding that was adequately managed with laser coagulation settings (1J-20Hz).
This initial case series in North America of the High Power Super Pulse Thulium Fiber Laser is promising for the treatment of urolithiasis. Sub-200 μm fibers and dusting settings up to 2400 Hz were utilized successfully. No specific complications related to use of the laser were seen.

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We conducted a retrospective chart review of 27 patients-7 men and 20 women, aged 47 to 94 years (mean: 71.3)-with symptomatic epiphora secondary to dacryostenosis who had undergone thulium: YAG (Tm:YAG) laser dacryocystorhinostomy (DCR). Among them, dacryostenosis had been documented in 35 eyes by dacryocystography. The Tm:YAG procedure involved the administration of local anesthesia, after which a 600-μm laser fiber was inserted into the lacrimal canaliculi and then into the nasolacrimal duct. Under endoscopic visualization, the DCR was performed anterior and inferior to the middle turbinate, which created an opening. Silicone stents were then inserted and tied intranasally. In the immediate postoperative period, all 27 patients noted initial improvement. During a follow-up of 22 days to 25 months (mean: 11.3 mo), 24 of the 27 patients (89%) remained symptom-free, while the remaining 3 patients (11%) experienced a treatment failure and required revision surgery. To the best of our knowledge, only two articles on thulium laser therapy for DCR have been previously published, both approximately 25 years ago; both involved the use of a thulium along with holmium and chromium in cadavers. As far as we know, our case series is the largest in the English-language literature that has documented the use of the thulium in laser therapy for DCR, and it is the only in vivo study. We found that DCR with the Tm:YAG laser was an effective and affordable option for patients with symptomatic epiphora secondary to lacrimal obstruction.

In lanthanide-doped materials, energy transfer (ET) between codopant ions can populate or depopulate excited states, giving rise to spectrally pure luminescence that is valuable for the multicolor imaging and simultaneous tracking of multiple biological species. Here, we use the case study of NaYF(4) nanocrystals codoped with Er(3+) and Tm(3+) to theoretically investigate the ET mechanisms that selectively enhance and suppress visible upconversion luminescence under near-infrared excitation. Using an experimentally validated population balance model and using a path-tracing algorithm to objectively identify transitions with the most significant contributions, we isolated a network of six pathways that combine to divert energy away from the green-emitting manifolds and concentrate it in the Tm(3+):(3)F(4) manifold, which then participates in energy transfer upconversion (ETU) to populate the red-emitting Er(3+):(4)F(9/2) manifold. We conclude that the strength of this ETU process is a function of the strong coupling of the Tm(3+):(3)F(4) manifold and its ground state, the near-optimum band alignment of Er(3+) and Tm(3+) manifolds, and the concentration of population in Tm(3+):(3)F(4). These factors, along with the ability to recycle energy not utilized for red emission, also contribute to the enhanced quantum yield of NaYF(4):Er(3+)/Tm(3+). We generalize a scheme for applying these energy concentration and recycling pathways to other combinations of lanthanide dopants. Ultimately, these ET pathways and others elucidated by our theoretical modeling will enable the programming of physical properties in lanthanide-doped materials for a variety of applications that demand strong and precisely defined optical transitions.

BACKGROUND: Since the early 1980s, CO(2), neodymium-doped yttrium aluminum garnet (Nd:YAG), and other laser prototypes have been widely used in neurosurgery as an intraoperative aid along with the cavitron ultrasonic surgical aspirator (CUSA), bipolar forceps, and microdissection. However, the English literature contains almost no reports on the use of thulium lasers during neurosurgical procedures.
METHODS: We report our experience with a thulium laser during the surgical removal of a tentorial meningioma. The intraoperative technique utilized, as well as the clinical and radiological results of the procedure, are described.
RESULTS: The thulium laser proved to be a useful tool during coagulation, shrinking, and resection of the basal implant of the tumor. Use of the laser made the surgical procedure faster and easier, and no intraoperative bleeding was noted. No side effects were observed.
CONCLUSIONS: Our experience indicates that thulium lasers are a valid aid during resection of benign intracranial tumors under microscope magnification. Additional studies are required to define fully the role of these lasers in neurosurgical procedures.

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