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To determine factors associated with failure of same-day trial of void (SDTOV) following holmium laser enucleation of the prostate (HoLEP).HoLEP is increasingly utilized for patients with benign prostatic hyperplasia. Advancements in technology have improved operative efficiency and hemostasis making same-day, catheter-free discharge possible.We conducted a retrospective review on 190 patients undergoing HoLEP from July, 2021 to January, 2022 by a single center. We assessed pre- and intra-operative variables associated with our primary outcome: failure of same-day catheter removal. Post-operative complications and outcomes at a ≤7 days and 3-month follow up were examined. Continuous and categorical variables were analyzed using unpaired t-tests (Mann Whitney) and chi-square, respectively. Univariate and multivariable logistic regression models were fitted to examine the associations of failed SDTOV.Of 190 candidates for a SDTOV, 90% (171/190) were successful. We found no difference between SDTOV success and failures with regards to age, comorbidities, presence of pre-operative urinary retention, anesthesia factors, operative time, volume resected, enucleation time, and morcellation time (all P0.05). Pre-operatively, 26.3% (50/190) were on antiplatelet and 6.3% (12/190) were on anticoagulation. While pre-operative antiplatelet therapy was not associated with SDTOV failure (P=0.78), pre-operative anticoagulation use was (4.7% vs. 21.1%, P=0.021). Patients who continued anticoagulation through surgery had the highest rate of SDTOV failure (2.3% (4/171) vs. 15.8% (3/19), P=0.023). For those with successful SDTOV, 4.1% (7/171) required catheterization following discharge. At 3 months, no patient required catheterization.On the day of surgery, patients eligible for SDTOV successfully voided 90% of the time. History of preop anticoagulation, whether continued or held, increased SDTOV failure.

To analyze the characteristics of ureteral stricture after ureteroscopic holmium laser lithotripsy and summarize our experience with the reconstructive strategies.This study retrospectively reviewed 42 patients with ureteral stricture after ureteroscopic holmium laser lithotripsy between December 2009 and December 2019. Patient demographics, laboratory data, imaging studies, perioperative variables, complications, and follow-up data were recorded. Surgical success was defined as relief of symptoms, improved/stabilized hydronephrosis, and stable renal function.The upper, middle, and lower thirds of the ureter were affected in 27, 6, and 7 cases, respectively. Multiple ureteral strictures were found in 2 patients. The median length of the stricture was 3.5 cm (range 1-30 cm). In the upper ureteral strictures, lingual mucosal ureteroplasty (8/27, 29.6%) is the most commonly used treatment method for stricture longer than 3 cm but shorter than 6 cm, followed by appendiceal onlay ureteroplasty (5/27, 18.5%). Four lower ureteral strictures ranging from 3 to 8 cm were repaired with Boari flap. Reconstructive strategies of the middle ureteral strictures included Boari flap, appendiceal onlay ureteroplasty and ureteroureterostomy. Patients with the length of the stricture longer than 8 cm or multiple strictures underwent ileal ureter replacement. The median follow-up was 27.3 ± 17.2 months. The overall success rate was 97.6%.Upper ureter is more vulnerable in ureteroscopic holmium laser lithotripsy. Sufficient follow-up and appropriate examination are necessary for diagnosis. Different treatment strategies need to be flexibly selected according to the location and length of the injury.

Background Holmium:yttrium-aluminium-garnet (Ho:YAG) laser is the gold standard for ureterorenoscopic (URS) lithotripsy. Thulium fibre laser (TFL) has recently been introduced as a new technology and may challenge Ho:YAG as the preferred laser owing to favourable properties as demonstrated in preclinical studies. Objective To evaluate and compare outcomes after URS lithotripsy with Ho:YAG and TFL. Design, setting, and participants In a prospective randomised trial, patients aged ≥18 yr with ureteral and/or renal stones (≥5 mm) scheduled to undergo day-case URS lithotripsy were invited to participate. In total, 120 consecutively admitted patients with signed consent were included for randomisation. Intervention URS lithotripsy with Ho:YAG or TFL. Outcome measurements and statistical analysis The primary outcome was the stone-free rate (SFR) assessed on noncontrast computed tomography at 3-mo follow-up. Secondary outcomes were the operative time and complications. Outcomes were compared between the groups using the t test and χ2 test. Results and limitations After a single session, the SFR was 67% in the Ho:YAG group and 92% in the TFL group, p = 0.001. For ureteral stones, the SFR was 100% in both groups, and for renal stones; 49% (Ho:YAG) and 86% (TFL), p = 0.001. Operative time was shorter using TFL (49 min) compared to Ho:YAG (57 min), p = 0.008. Bleeding that impaired the endoscopic view was the most frequent intraoperative adverse event and occurred in 13 patients (22%) in the Ho:YAG group and three (5%) in the TFL group, p = 0.014. Conclusions In this study, significantly more patients with renal stones achieved stone-free status and fewer experienced intraoperative complications using TFL compared to Ho:YAG. TFL is the emerging laser of choice for stone lithotripsy. Patient summary We compared outcomes after ureterorenoscopic treatment of kidney and ureteral stones using two different lasers. Our results show that the new thulium fibre laser technology is superior to the current standard laser (holmium:YAG) in clearing kidney stones and reducing operative complications. publishedVersion

To compare operative efficiency of Holmium laser enucleation of the prostate (HoLEP) using both the standard multi-incisional approach and en-bloc enucleation with early apical release during the initial learning curve.We retrospectively reviewed the initial 95 consecutive men who underwent HoLEP between April 2019 and September 2020 by a single surgeon. We compared patient demographics, and pre-, intra-, and post-operative metrics between both groups. Differences between groups were evaluated with Mann-Whitney U and Kruskal-Wallis tests.Forty-nine patients underwent the standard HoLEP approach, and 46 patients underwent the en-bloc approach. Compared to a standard HoLEP, the en-bloc approach was associated with decreased operative time (131.11 minutes vs 153.59 minutes, P = .007) with similar weights of tissue removed. Operative efficiency, as measured by grams of prostate tissue removed per minute, was greater for the en-bloc approach (0.49 g/min vs 0.36 g/min, P = .005). There was no difference in length of stay (0.91 days vs 0.96 days, P = .383), laser efficiency (4.41 kJ/g vs 4.83 kJ/g, P = .200), or number of post-operative complications (10 vs 6, P = .236) between the groups.Utilization of the en-bloc technique during the initial learning curve allows for a faster, more efficient operation without any difference in functional outcomes or major complications compared to a standard HoLEP.

To assess outcomes following Holmium Laser Enucleation of Prostate (HoLEP) in men with prostate volumes ≥150cc and compare this to men with prostate volumes ≤150 cc.We analyzed our prospective database of consecutive patients undergoing HoLEP in a single tertiary public hospital between October 2016 and January 2019. We excluded patients with clinically significant prostate cancer or neurogenic bladders. Preoperative prostate volume was measured on MRI or ultrasonography. Perioperative variables and functional outcomes were recorded.Of 304 HoLEPs performed, we included 97 patients with prostate volume of ≥150 cc and 186 patients with prostate volume150 cc. Comparing both cohorts (≥150 cc vs150 cc): mean age was 71.5 vs 68.3 years, prostate volume 195 cc vs 93 cc, preoperative Qmax 9.6mL/s vs 10mL/s, American Urology Association Symptom Score (IPSS) 21 points vs 20.5 points; mean PSA 13.2µg/L vs 8.8µg/L; laser duration 86 vs 59 minutes; morcellation duration 29 vs 14 minutes; enucleated weight was 124 g vs 60 g. One patient (1%) from the ≥150 cc cohort required a surgical procedure for stress urinary incontinence, and none from the150 cc cohort, but this did not achieve statistical significance (P = .12). There were no statistically significant differences in postoperative Qmax (32.3 vs 26.4 mL/s; P = .12), IPSS (5.9 points vs 7.3points; P = .23), mean PSA (3.9 µg/L vs 2.2 µg/L; P = .60), stricture incidence (1% vs 2.7%; P = .63), or significant stress urinary incontinence (4.1% vs 0.5%; P = .08).Our large series demonstrates that HoLEP is safe and effective in patients with massive prostates (≥150 cc), with similar outcomes compared to patients with prostates150 cc.

Background Limited research has focused on success with hospital discharge on the same day of surgery after holmium laser enucleation of the prostate (HoLEP). Objective To determine the success of same-day discharge in our HoLEP cohort and factors associated with this approach. Design, setting, and participants A retrospective review of our prospectively maintained HoLEP database demonstrated that 473 adult males underwent HoLEP from July 2018 to December 2019 at a tertiary referral center and high-volume HoLEP hospital. Patients were divided into groups according to planned inpatient admission (PIA), successful same-day discharge (SDD), or unplanned admission (UA). Outcome measurements and statistical analysis The PIA, SDD, and UA groups were assessed for differences in preoperative demographic data, perioperative surgical data, and postoperative follow-up data. SDD and UA were then compared to determine if any specific factors predicted UA, including univariate and multivariate logistic regression analyses. Results and limitations Age (p = 0.0049), use of anticoagulation (p = 0.037), American Society of Anesthesiologists score of 3–4 (p = 0.0017), and enucleation time (p=0.0178) were significantly higher in the PIA group. Morcellation time (p = 0.0059) and the rate of bedside catheter irrigation (p = 0.04) were higher in the UA group. The SDD group had the highest rate of successful voiding trial (p = 0.0001). Among the three groups, there was no difference in the rate of postoperative complications (p = 0.141). In a comparison of the SDD and UA groups, morcellation time (p = 0.041), the rate of bedside clot evacuation (p = 0.004), and successful voiding trial (p = 0.003) all favored SDD. There was no difference in 90-d complications (p = 0.536). A limitation is the retrospective nature of this study. Conclusions HoLEP can be successfully performed as day surgery without an increase in postoperative complications. HoLEP as day surgery is possible for any patient who does not require admission for medical comorbidities. Patient summary Same-day discharge (SDD) after holmium laser enucleation of the prostate (HoLEP) is possible and is successful in 87.4% of patients. Patients with longer morcellation times and with post-procedure hematuria with clots are more likely to have an unplanned admission. Use of a 120-W modulated-pulse laser resulted in a higher rate of SDD success. The culture change to day surgery is time-intensive owing to education of the postsurgical care units and clinic staff, and in our experience took approximately 9 mo to seamlessly integrate SDD as our HoLEP standard of care.

Holmium doped BaTiO3 ceramics were prepared by a solid-state reaction. Colossal dielectric permittivity (≥105) and a very low loss tangent (

Contains fulltext : 238625.pdf (Publisher’s version ) (Open Access) Microbrachytherapy with radioactive holmium-166 ((166)Ho) microspheres (MS) has the potential to be an effective treatment method for brain malignancies. Direct intratumoural delivery of (166)Ho-MS and dose coverage of the whole tumour are crucial requirements. However, currently no dedicated instruments for controlled intratumoural delivery exist. This study presents an administration device that facilitates this novel magnetic resonance imaging (MRI) -guided intervention. The bioceramic alumina oxide cannula creates a straight channel for a superelastic nitinol precurved stylet to control spatial deposition of Ho-MS. End-point accuracy of the stylet was measured during insertions in phantoms. Imaging tests were performed in a 3 Tesla MRI-scanner to quantify instrument-induced artefacts. Additionally, the feasibility of non-radioactive holmium-165 ((165)Ho)-MS delivery with the administration device was evaluated in a brain tumour simulant. Absolute stylet tip error was 0.88 +/- 0.61 mm, instrument distortion in MRI depended on needle material and orientation and dose delivery of (165)Ho-MS in a brain tumour phantom was possible. This study shows that the administration device can accurately place the stylet for injection of Ho-MS and that visualization can be performed with MRI.

Endocorporeal laser lithotripsy (ELL) is currently the gold standard for the treatment of renal stones during retrograde intra-renal surgery (RIRS). The newly-authorised thulium fibre laser (Tm-Fibre) in now evaluated as a holmium:yttrium-aluminium-garnet (Ho:YAG) laser alternative, which is the most well-known laser source for ELL. This update aimed to present the fundamentals of pulsed lasers for EEL [technology, period, pulse characteristic (rate, duration, energy, shape), peak power, average power], and the available lithotripsy modes for both Tm-Fibre and Ho:YAG lasers.

The study of polarizability, optical basicity, and electric susceptibility carried out on the new and very rare set of bismuth - tellurite glasses doped with Ho3+ ions were fabricated by the conventional melt quenching process. The non-crystalline nature was confirmed by X-ray diffractometer measurements. Physical properties such as rare earth ion concentration, interionic distance, polaron radius, and average tellurium - tellurium separation were investigated by appropriate formulae. By UV absorption spectra, optical properties of Ho3+ ions doped glasses were found in the wavelength limit from 400 to 700 nm. The optical properties like optical dielectric constant, electronic polarizability, metallization criterion, electronegativity, optical basicity, and electric susceptibility were measured with appropriate mathematical relations. The impact of Ho3+ ions on nonlinearity in optical parameters discloses bismuth tellurite glass as a new applicant for holmium doped fiber amplifier applications.

A novel functional ceramic or glass pigment of monoclinic holmium molybdate (Ho2MoO6) with ‘allochroic effect’ was synthesized via co-precipitation and subsequent low-temperature sintering with different mineralizers (i.e., lithium chloride, sodium fluoride and boric acid). Effects of solution pH value and mineralizer type/content on Ho2MoO6 formation at different sintering temperatures and time were investigated. The results reveal that the solution pH value in co-precipitation reaction has an influence on the element ratio of Mo and Ho in the precursor and the pigment purity. The sintering temperature of forming sole Ho2MoO6 phase is decreased by 200 °C and the sintering duration is reduced in the presence of 5 wt % lithium chloride due to the decreased crystallization activation energy. Meanwhile, Ho2MoO6 pigment as powder or coating on ceramic tile and glass exhibits various colors (i.e., pale yellow, salmon, mustard and coral) under different illuminants (i.e., incandescent lamp A, solar-light D65, cool white fluorescent lamp F2 and three-band fluorescent lamp F11).

Ho2O3 transparent ceramics were fabricated by vacuum pre-sintering combined with hot isostatic pressing (HIP) post-treatment at relatively low temperature from high-purity Ho2O3 powder calcined at 1000 °C for 4 h. The optimal Ho2O3 ceramic sample prepared by vacuum pre-sintering at 1250 °C and HIP post-treating at 1450 °C has a dense microstructure with average grain size of 0.77 μm, and the in-line transmittances reach 80.7 % at 1550 nm and 76.7 % at 1064 nm. The effect of air annealing on the optical quality of Ho2O3 ceramics was studied, and the existence of compressed pores in the HIP-ed Ho2O3 ceramics was confirmed. The Verdet constants of Ho2O3 ceramics were measured to be -47.4 rad/(T m at 1064 nm and -15.4 rad/(T m at 1561 nm. High transmittance and large Verdet constant in the wavelength regions 1–1.07 μm, 1.3–1.5 μm make Ho2O3 transparent ceramics promising for magneto-optical devices for lasers based on Yb-, Nd-doped materials and telecom lasers. © 2020 Elsevier Ltd 19-52-53014; Chinese Academy of Sciences, CAS: QYZDB-SSW-JSC022; Russian Science Foundation, RSF: 18-13-00355; National Key Research and Development Program of China, NKRDPC: 2017YFB0310500 This work was supported by the National Key R&D Program of China (Grant No. 2017YFB0310500 ), the Special Exchange Program of Chinese Academy of Sciences (Plan B) , the key research project of the frontier science of the Chinese Academy of Sciences (No. QYZDB-SSW-JSC022 ), partially by the Research Project of the Russian Science Foundation (No. 18-13-00355 ) and Verdet constant measurements was done under NSFC-RFBR Cooperative Research Projects Grant 19-52-53014.

Holmium doped EuF3 nanoparticles (EFHA) have been synthesised in presence of alanine using wet chemical method. EFHA nanoparticles belongs to hexagonal phase with a = b = 6.980 A and c = 7.312 A. The Debye-Scherer particle size from XRD analysis is 42.79 nm. SEM studies show formation of flakes like structures with granular size of about 14 nm. TEM analysis shows formation of assorted size nanoparticles consisting of hyperboloids, spear shaped structures and globular aggregates. The planes indicated by the SAED pattern remains confirmed from XRD analysis. Multiple peaks below 400 nm in UV –Vis spectra indicate formation of quantum dots. Comparative vibrational analysis of FTIR and FT-Raman has been carried out. PL spectra shows intense peak at 654 nm (red) due to 5D0 → 7F3 transition.

Advantage of small amount (0.5 mol%) of holmium ion (Ho+3) substitution in the sodium bismuth titanate (NBT) on its electrical properties had been highlighted. Na0.5Bi0.5TiO3and Na0.5Bi0.495Ho0.005TiO3(NBT-Ho) had been synthesized by using solid state technique. In the dielectric properties, depolarization temperature (Td) and temperature at maximum dielectric constant (Tm) were increased to ˜180 °C and ˜ 355 °C, respectively in compared to Td˜165 °C and Tm˜ 325 °C of pure NBT. In addition, improved insulating nature was found in holmium substituted ceramic, which was confirmed by room temperature leakage current density versus electric field (J-E) measurement and temperature dependent impedance analysis. It showed five times lesser leakage current density at ˜45 kV/cm over its parent ceramic NBT. Leakage current density of holmium substituted NBT in the function of electric field (J versus E graph) displayed that electrical conduction follows the ohmic behavior up to ˜ 7.5 kV/cm electric field, and thereafter, up to ˜ 20.1 kV/cm, space-charge limited conduction mechanisms (SCLC) became to dominate. Moreover, enhanced electromechanical coupling coefficient (kp˜18.67%) in the NBT-Ho in comparison to pure NBT (kp˜18.17%) was obtained.

The work is devoted to obtaining of transparent nanocomposite materials as low loss, highly thermally conductive materials for potential laser applications. We report Ho3+:Y2O3–MgO nanocomposite ceramics with excellent mechanical and optical properties by combining glycine-nitrate process and spark plasma sintering. Morphology, structural-phase state, infrared transmittance and luminescence depending on the holmium concentration (0–12 at.%) were studied for the first time. It was found that optical transmittance reaches 75%@6000 nm for 3 at.% Ho3+:Y2O3–MgO ceramics. The absorption cross-section at 1931 nm and the emission cross-section at 2118 nm were determined to be σabs = 0.51 × 10−20 cm2 and σem = 0.29 × 10−20 cm2, respectively. Based on the testing results of luminescent characteristics it was demonstrated that Ho3+:Y2O3–MgO nanocomposite is a promising material for high-power eye-safe lasers operating in the 2 μm wavelength range.

Spin valves with holmium layers and three-layer structures metal/Ho/metal were prepared by magnetron sputtering. A holmium layer in the spin valves is polycrystalline with weak axial texture. The structural coherence length along the hexagonal c-axis is approximately 2/5 of the total thickness of the holmium layer. Field dependences of the spin valves magnetoresistance were measured at different temperatures. Correlation was revealed between magnetic state in holmium layer and the shape of magnetoresistive curve. Deviation of magnetic moments of the reference layer and the adjacent part of holmium from the applied magnetic field was investigated. The field induced mobility of the magnetic helicoid in holmium layers was revealed.

This work reports on the analysis of structural and spectroscopic properties of the fluoroindate glasses co-doped with Er3+/Ho3+. Structural analysis showed that erbium and holmium ions were modifier ions and depolymerizedof the fluoroindate glass network. The energy transfer processes between rare - earth ions in fluoroindate glasses pumped by and 980 nm laser diode have been also examined. Due to partial Er3+ → Ho3+ energy transfer and superposition of Er3+: 4I11/2 → 4I13/2 (2.77 μm)+ Ho3+: 5I6 → 5I7 (2.85 μm) radiative transitions in fluoroindate glass co-doped with 0.8ErF3/1.6HoF3, a broadening 3 μm luminescence (Δλ= 201 nm) was obtained. The overall energy transfer efficiency ηET1 + ηET2 was calculated to be 95% indicating efficient sensitization of the holmium ions by erbium.

Summary High saturation magnetization, hysteresis-less long linear response range, and resistance to device fabrication conditions are figures of merit for magnetic materials. Despite advances in materials research, many high-saturating micro- and nanomagnetic materials are hysteresis-prone, have short linear ranges, and are sensitive to oxidation, resulting in device inefficiencies in high-frequency electronics and unpredictable responses in magnetic sensing applications. Holmium oxide is a promising material because of its high magnetic susceptibility, but synthetic options are limited, with low-temperature magnetism incompletely characterized. Here, we present physical vapor deposition synthesis and material characterization of polycrystalline holmium oxide thin films. The product has saturation magnetization exceeding 2 Tesla, linear range (μ0H) also exceeding 2 Tesla, zero magnetic remanence and coercivity, and resistance to harsh processing conditions including oxygen plasma and concentrated hydrofluoric acid etching, making these thin films ideal for fabricating next-generation nanoscale magnetic devices in advanced scientific and engineering applications.

Purpose To evaluate the safety and feasibility of same-day treatment, including the simulation procedure for assessment of intrahepatic and extrahepatic distribution of the microspheres, with holmium-166 (166Ho)-radioembolization. Materials and Methods This was a secondary analysis of patients included in the 4 prospective studies (HEPAR I, HEPAR II, HEPAR PLuS, and SIM) on 166Ho-radioembolization. The technical success rate of the same-day treatment protocol, defined as the number of patients who completed the same-day treatment, was measured. Total in-room time, duration of the scout procedure, time to imaging, and duration of the treatment procedure were recorded. Reasons for discontinuation or adjustment of treatment were identified. Adverse events that occurred during the treatment day were recorded. Results One hundred five of 120 scheduled patients completed the same-day treatment with 166Ho-radioembolization (success rate, 88%). After the simulation procedure, treatment was cancelled in 15 patients because of extrahepatic deposition (n = 8), suboptimal tumor targeting (n = 1), unanticipated vascular anatomy (n = 5), and dissection (n = 1). In another 14 patients, the treatment plan was adjusted. The median total procedure time (ie, simulation, imaging, and treatment) was 6:39 hours:minutes (range, 3:58–9:17 hours:minutes). Back pain was a major same-day treatment-related complaint (n = 28). Conclusion 166Ho-radioembolization as a same-day treatment procedure is feasible in most selected patients, although treatment was adjusted in 12% of patients and cancelled in 12% of patients. This approach might be beneficial for a select patient population, such as patients needing a radiation segmentectomy.

Nanopowders of holmium zirconate (Ho2Zr2O7) synthesised through carbon neutral sol-gel method were pressed into pellets and individually sintered for 2 h in a single step sintering (SSS) process from 1100 °C to 1500 °C at 100 °C interval and in a two step sintering (TSS) process at (I) −1500 °C for 5 min followed by (II) - 1300 °C for 96 h. Relative density of each of the sintered pellet was determined using the Archimedes’ technique and the theoretical density was calculated from crystal structure data. Grain size was obtained from SEM micrographs using ImageJ. Pellets processed by TSS have been found to be denser (98 %) with less grain growth (1.29 μm) as compared to the pellets processed using SSS process. Ionic conductivity of Ho2Zr2O7 pellets sintered by two different processes was measured using ac impedance spectroscopy technique over the temperature range of 350 °C–750 °C in the frequency range of 100 mHz–100 MHz for both heating and cooling cycles. The temperature dependence of bulk (2.67⨯10−3 Scm−1) and grain boundary (2.50⨯10−3 Scm−1) conductivities of Ho2Zr2O7 prepared by TSS process are greater than those processed by SSS process suggesting the strong influence of processing conditions and grain size. Results of this study, indicates that the TSS is the preferable route for processing the holmium zirconate as it can be sintered to exceptionally high densities at lower temperature, exhibits less grain growth and enhanced ionic conductivity compared with the samples processed by SSS process. Hence, holmium zirconate can be considered as a promising new oxide ion conducting solid electrolyte for intermediate temperature SOFC applications between 350 °C and 750 °C temperature range.

The production cross sections of 165–168Tm radioisotopes produced in α-particle induced reactions on 165Ho were measured from 49.6 MeV down to the respective thresholds using the stacked-foil activation technique and HPGe gamma-ray spectrometry. The measured excitation functions were compared with previous measurements as well as the TENDL-2019 library. We also calculated the thick target yields for all the assessed radioisotopes by integration of the measured excitation functions and found that they show good agreement with the directly measured thick target yields except for 168Tm production.

Three different rare earth metal (samarium, neodymium and holmium) oxides were synthesized by adapting organic and inorganic routes. The influence of synthesis route over the physico-chemical characteristics of the rare earth metal oxides was studied using X-ray diffraction, FT-IR, thermogravimetric analysis, microscopy (FESEM and HRTEM), N2-physisorption and diffusive reflective ultraviolet-visible spectroscopy techniques. The XRD, electron microscopy and N2-physisorption results indicated that the samples synthesized by organic route possessed smaller crystallite/particle size and high surface area with macro size pores compared to the samples synthesized by inorganic route. The synthesis conditions also influenced the morphology of the samples. The samples synthesized by organic route possessed sheets like morphology with large spaces in between the sheets, in contrast highly agglomerated particles were observed in case of samples synthesized by inorganic route. All the synthesized rare earth oxides were utilized as photocatalysts for degradation of crystal violet dye under visible light irradiation. The samples synthesized by organic route exhibited high photocatalytic efficiencies. Samarium oxide synthesized using organic route offered the superior photocatalytic performance as this sample possessed low band gap energy, high surface area, pore volume and presence of surface reactive −OH groups. In addition, the synthesized rare earth metal oxide catalysts exhibited excellent recyclability for photocatalytic crystal violet degradation. Keywords: Rare earth metal oxide, Organic route, Inorganic route, Structural properties, Photocatalytic activity

Customisation of the lasing characteristics of rare-earth ions activating various materials for practical applications requires fundamental knowledge of the structure and dielectric correlation. Based on these factors, a new series of glass ceramics of composition (40-x)P2O5 –30B2O3 –30ZnSO4 –xHo2O3 (x = 0.0, 0.4, 0.5, and 0.6 mol%) were prepared using the melt-quenching method. As-prepared samples were characterised using various techniques to determine the effect of holmium ion (Ho3+) doping on their structure and dielectric traits. XRD patterns of as-quenched samples confirmed their glass-ceramic characteristics. Holmium ion concentration-dependent Raman and FTIR analyses revealed the structural enhancement in the glass ceramics. The presence of Zn, S, B, P, O, and Ho in the glass ceramics was disclosed by the XPS spectra, and the ratio of the bridging to non-bridging oxygen atoms was evaluated by analysing the O1s peaks. The recorded room temperature complex impedance spectra of the samples in the range of 10 3 – 10 5 Hz were influenced by the predominant glassy and dormant crystalline structures. The UV–Vis–NIR data (in the range of 206–310 nm) and the impedance spectra (3 × 10 12 –3 × 10 14 nm) were analysed to evaluate the dielectric features of the samples. The considerable increase in the frequency-dependent AC conductivity and its slight reduction with Ho3+ incorporation was ascribed to the dopant ion-induced formation of quasi-molecular complexes (such as bridging oxygen and ligands) in the host network. A correlation between the structure and dielectric attributes of the titled glass ceramics was established. In short, the Ho3+-incorporated customised structures and dielectric properties of the newly proposed glass-ceramic composition were affirmed to be prospective for sundry applications.

Nowadays, a wide class of rare earth orthoferrites is of great interest among acid-base catalysts due to their high activity and the possibility of magnetic recovery. However, the synthesis of chemically and phase-pure rare-earth orthoferrites in the form of nanocrystals with developed surface and microstructure is still a difficult task. In this work, we report for the first time a successful synthesis of phase-pure holmium orthoferrite (HoFeO3) nanocrystals with a porous microstructure and a branched surface via simple glycine-nitrate combustion approach. Holmium orthoferrite nanocrystals were characterized by using energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), 57Fe Mossbauer spectroscopy and low-temperature sorption-desorption of nitrogen. Acid-base properties of the surface and catalytic activity of porous HoFeO3 in process of n-hexane conversion were analyzed as well. Finally, a magnetic recovery procedure was performed for the spent catalyst to analyze its efficiency for synthesized HoFeO3. The elemental composition of the sample corresponds to holmium orthoferrite (48.8 and 51.2 at. %, for Ho and Fe, respectively) with the absence of any impurities as it was shown by EDX. The PXRD results show that the synthesized HoFeO3 nanocrystals have an orthorhombic structure (space group Pbnm) and an average crystallite size of 62 ± 5 nm. The Rietveld method was used to refine the unit cell parameters as follows: a = 5.254(1) A, b = 5.575(3) A, c = 7.598(4) A; Rwp = 2.45%. The Mossbauer spectrum of HoFeO3 evidenced the magnetically ordered state of nanocrystals and it is represented by a sextet with quadrupole splitting (QS), of 0 mm/s, an isomeric shift (IS) of 0.36 mm/s, and an effective magnetic field (Heff) of 497 kOe. Sorption-desorption of nitrogen shows that the holmium orthoferrite has a predominantly macro- and mesoporous structure, also confirmed by SEM, with specific surface area and total porosity values of 31 m2/g and 0.071 cm3/g, respectively. The analysis of the acid-base properties of the surface of the porous HoFeO3 evidences a high concentration of the aprotic (Lewis) acidic (pKa = 14.2) and basic (pKa = -4.4) sites, as well as of the Bronsted weak acid (pKa = 6.4) sites. The catalytic activity of holmium nanocrystalline in process of n-hexane conversion was analyzed and compared with commercial dehydrogenation (CD-1) and cracking (ZSM-5) catalysts. The n-hexane conversion and cracking products selectivity displayed by HoFeO3 are comparable to those of the reference catalysts, and the selectivity to dehydrogenation and especially isomerization products significantly exceeds the values of CD-1 and ZSM-5; low n-hexane oligomerization product selectivity of HoFeO3 catalyst was observed as well. A high recovery rate (~97%) achieved as a result of the magnetic separation of the spent o-HoFeO3-based catalyst from the reaction mixture, followed by heat treatment at 600 °C for 1 h. These results allow us to conclude that synthesized porous HoFeO3 can be considered as a promising basis for new catalytic materials for cracking, dehydrogenation and isomerization processes with a possibility of highly efficient magnetic recovery.

A series of neodymium–doped holmium molybdate (Ho1-xNdx)2MoO6 (x = 0-0.8) color pigments with ‘allochroic effect’ were synthesized by a solid-phase reaction method under different conditions (i.e., sintering temperature, sintering time, and neodymium ions (Nd3+) doping amount). The as-synthesized pigments were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetry and differential scanning calorimetry (TG-DSC), ultraviolet–visible–near infrared (UV-VIS-NIR) spectrophotometry and CIE L*a*b* color scale. The results show that the adulteration of Nd3+ ions does not alter the crystal structure of Ho2MoO6 basically, but causes the lattice expansion for the pigments sintered at

A novel all fibre Q-switched Thulium-doped fibre laser (TDFL) is reported which includes a short length of a Thulium–Holmiumco-doped fibre (THDF) as a saturable absorber. A high repetition rate (27.26 kHz) coupled with a low pulse width ( 19 . 06 μ s ) is obtained for single wavelength Q-switched pulse operation at an output wavelength of 1911.5 nm using a pump power of 200 mW. Increasing the pump power from 200 mW to 700 mW results in the repetition rate increasing from 27.26 kHz to 99.67 kHz and the pulse width decreasing from 19 . 06 μ s to 920 ns. The centre wavelength of the single Q-switched pulse was also red shifted from 1911.5 nm to 1932.5 nm with increasing the pump power. A 45 m length single-mode fibre (SMF-28) provided dispersion compensation, and effectively an SMF-THDF-SMF structure is inserted in the cavity which operates in a similar manner to an SMF-MMF-SMF structure, providing a strong multimode interference effect which supports dual-wavelength operation. A stable dual-wavelength Q-switched pulse was achieved at a threshold pump power of 213 mW. The dual-wavelength Q-switched pulse operation was generated at 1911.5 nm and 1914.5 nm with a repetition rate of 8.45 kHz and pulse width of 20 . 02 μ s . The dual-wavelength spacing of this pulse operation was 3 nm, which was in good agreement with calculations based on the multimode interference effect induced by the THDF. The repetition rate increased from 8.45 kHz to 70.65 kHz and the pulse width decreased from 20 . 02 μ s to 870 ns with increasing pump power. At the maximum pump power of 700 mW, the maximum output power was measured as 27.4 mW. The experimental results confirm that the THDF can be utilized as a SA to generate a stable and tunable single-wavelength Q-switched pulse output as well as dual-wavelength Q-switched pulse in the 2 . 0 μ m wavelength region.

The amphoteric element holmium was used to dope X9R Nb-modified BaTiO3-(Bi0.5Na0.5)TiO3 ceramics (BTBNT-Nb) by a conventional solid-state reaction method. The effect of Ho2O3 doping on the dielectric and electric properties of ceramics were investigated. X-ray diffraction results showed that the rare earth of Ho3+ can occupy A- and B-sites of BTBNT-Nb. All samples met X9R specifications and the insulation resistance of the 0.5 mol% Ho2O3 doped ceramic was 1.05 × 1013 Ω/cm. The sintering temperature strongly influenced the core–shell structure of ceramics Transmission electron microscope images revealed that the size of ferroelectric domain in the core decreased with increasing temperature. Multilayer ceramic capacitor chips with ten active dielectric layers were prepared and characterized.

This work is devoted to investigations of unclassified spectral lines in atomic holmium, aiming at identification of new electronic levels and determination of their hyperfine structure. Altogether 113 unclassified lines were investigated with the method of laser induced fluorescence in a hollow cathode discharge lamp. As a result, 35 odd-parity electronic levels with previously unknown energies were identified; for all of them the hyperfine structure constants A and B were also determined. The data reported greatly facilitated the semi-empirical fit of the fine and hyperfine structure of the odd-parity level system, performed in our group.

In this work investigations of the hyperfine structure of 66 spectral lines of the holmium atom were performed with the method of laser induced fluorescence in a hollow cathode discharge lamp. Altogether 43 odd-parity levels, involved as the upper levels in the transitions studied, were investigated. For about half of them the hfs constants A and B were evaluated for the first time. For some levels, already examined in earlier works, supplementary results were obtained; for a few levels it was possible to compare our results with earlier literature data. For 4 levels J quantum numbers were changed with respect to the available literature values. As a by-product, also improved hfs constants for the lower even-parity levels were determined. The data reported facilitated the semi-empirical fit of the fine and hyperfine structure of the odd-parity level system, performed in our group.

Holmium (Ho3+) -doped bismuth-germanate glasses with the chemical combination of (40-x) GeO2 + 20 Bi2O3 + 20 Na2O + 10 Gd2O3 + 10 BaO + x Ho2O3 (x = 0.1, 0.5, 1.0, 1.5 and 2.5) have been prepared by melt-quenching method. These glasses were characterized for spectroscopic properties through optical absorption, photoluminescence excitation and photoluminescence emission. Judd-Ofelt (JO) intensity (Ωλ, λ = 2, 4, 6), and radiative parameters were evaluated with the help of the absorption spectra. Intense emission band was observed at a wavelength of 548 nm in the green region compared to other emission bands. Stimulated emission cross-section of GeBiNaGdBaH was found to be 0.18 × 10−20 cm2 and compared with other reported glasses. High lifetime of the 5S2+5F4 level is reported as 25 μs for the GeBiNaGdBaH15 glass. The CIE chromaticity diagram has demonstrated the strong emission for the GeBiNaGdBaH glasses in the green region at around 548 nm, and suggest that the glasses could be useful for green lighting applications.

First-principles calculations of the structural, magnetic and elastic properties of Holmium pnictides compounds HoX (X = As, Sb, and P) in the rock-salt structure, as a function of pressure, have been performed using the Density Functional Theory (DFT). We have used two full-potential methods: full potential linearized augmented plane wave (FP-LAPW) implemented in WIEN2k code and full-potential local-orbital minimum-basis in FPLO code. The calculations are carried out within a framework of the generalized gradient approximation (GGA) and GGA+U (where U = 5 eV is the Hubbard correlation term). the total magnetic moments of HoAs, HoSb, and HoP using GGA approximation are 5.85, 6.35, and 5.70 µB respectively and using GGA+U are 5.803, 6.208, 5.634 µB respectively. We investigated the effect of pressure on the magnetic properties of these compounds, using GGA approximation. The total magnetic moment of HoP shows small variation at low pressure, but it decreases rapidly at high pressure to reach 3.87 µB at 50 GPa.

In this work, the temperature dependence of Curie-spin (CS) contribution to the relaxation rate was studied by 1H NMR under magnetic fields of 7.05 and 18.79 T using the Ho complex with DOTA as an example. This is the first example of the detailed study of the temperature dependence of Curie-spin contribution to the paramagnetic transverse relaxation rate enhancements (CS-PTRRE) in lanthanide complexes other than dysprosium, taking into account the magnetic field strength and change of viscosity with temperature. It was found that due to the substantial temperature dependence of CS-PTRRE the Ho complex with DOTA is the first example of a temperature sensitive relaxation paramagnetic lanthanide probe for in situ temperature control by NMR/MRI in water environment at high magnetic fields.

Luminescent temperature sensors operated at wide temperature interval show promising technological potential. Here, the holmium and ytterbium co-doping of cubic phase Sc2O3:x%Ho3+/8%Yb3+ (x = 1.0–3.0) nanocrystals are synthesized by a facile coprecipitation annealing method. The strongest green and red up-conversion emission was obtained from Sc2O3:2%Ho3+/8%Yb3+ with 980 nm excitation. The temperature sensitivity steadily increases to 0.1285 K−1 at ∼83 K during cooling. Accordingly, the ratio of green and red up-conversion emission increases from 0.966 to 3.469 when cooling from 483 K to 83 K. This is in accordance with the changing of cross-relaxation process at different temperatures. This work highlights the fascinating potential of lanthanide-loped Sc2O3 for highly sensitive wide temperature monitoring.

The full-potential linearized augmented plane wave method (FP-LAPW) within the framework of density functional theory (DFT) have been employed to study the structural, magnetic and electronic properties of double perovskite-based rare earth compound Ba2HoReO6, those properties were determined by generalized gradient (PBE-GGA) and GGA + U approximations for the exchange-correlation functional. According to obtained results, Ba2HoReO6 ordered double perovskite compound shows a half-metallic behavior with the indirect energy-gap value equal to 0.32 eV in spin down bands, located at (LV-ΓC) direction with integer magnetic moment amounts to 6.0 μB using GGA approximation. On the other hand, using GGA + U approximation, Ba2HoReO6 has a metallic behavior when U = 2, 4 and 6 eV. While its character changes when U = 8eV, and then become half-metallic behavior with direct energy-gap equal to 1.93eV in spin-up bands, located at (ΓV-ΓC) direction, with magnetic moment amounts to 2.0 μB at U = 8eV. The results obtained concerning these different properties are the first prediction of Holmium rare-earth based double perovskite Ba2HoReO6. Our compound is identified as potential candidate for spintronic applications and high-performance electronic devices.

The pyrochlore oxides are of potential interest as ion conducting electrolyte for intermediate temperature solid oxide fuel cell (SOFC). Nanopowders of holmium zirconate have been synthesised through ion-exchange between sodium alginate gel and metal complex solution followed by its thermal decomposition. Nanoparticles of Ho2Zr2O7 were obtained by calcining the dried gel beads at 700 °C for 2 h and 6 h duration respectively. An insight into calcination has been obtained employing simultaneous thermogravimetric analysis and differential scanning calorimetry (TGA/DSC). Thermal decomposition was also followed using High Temperature X-ray Diffraction (HTXRD) in static ambient atmosphere. Results from TGA/DSC and HTXRD corroborate with each other. Fine crystalline nanopowders of single phase Ho2Zr2O7 could be obtained after thermal decomposition at relatively low temperature (600–700 °C). Powder X-ray diffraction (XRD) revealed that the material has crystallized as single phase cubic Ho2Zr2O7 with defect fluorite structure. XRD and Raman spectroscopy were used to analyse the local structure of holmium zirconate. XRD scans of holmium zirconate and holmium hafnate prepared through identical method have been compared and the effect of cationic radius of Zr4+ and Hf4+ on B-site was studied. The crystallographic data obtained from XRD and transmission electron microscopy (TEM) are in good agreement with each other. This sol-gel method also referred as Leeds Alginate Process (LAP) is simple, cost effective, energy efficient and carbon neutral for the preparation of pyrochlore oxides (A2B2O7) solid electrolyte material for SOFC.

The series of Tm3+/Ho3+ co-doped vanadates based on Ca3(VO4)2 was obtained by Czochralski method. The trivalent doping ions were introduced into the melt in the form of oxides without any additional compensating impurities. The spectroscopic investigations showed anisotropic character of optical properties of the material. For optimal output mirror reflectivity of 94% the oscillation spectrum for holmium ions was measured to be centered at about 2070 nm with oscillation spectrum width of about 20-nm width at half maximum. Slope efficiency 5% for Ho3+ ions under 792 nm thulium pumping was obtained. Broadband tuning of Ho3+ ions oscillation wavelength within 2020–2115 nm spectral range was obtained in selective cavity with SiO2 filter.

Holmium:YAG laser is currently the dominant lithotripter used during retrograde intrarenal surgery. The laser energy is delivered to the target via flexible optical laser fibers. The performance characteristics of laser fibers vary. The diameter, flexibility, resistance to fracture with bending, and tip configuration are all important factors that contribute to a fiber's overall performance. Understanding these characteristics assists the end user with proper fiber selection for procedures.

Magnetic phases of holmium films are associated with the intensity of the magnetic neutron scattering. It is shown that each magnetic phase of the system (fan, helifan, spin-slip, helix and ferromagnetic) exhibits a characteristic profile of scattering which can be used as a fingerprint to identify it. In this paper, we present theoretical results obtained for holmium films 24 monolayers thick at a fixed temperature and in the presence of a dc magnetic field applied along the basal plane. A self-consistent local field algorithm was used to obtain the equilibrium configurations of the magnetic moments of the film and, with these results, the spin-spin correlation functions which determine the shape of the neutron scattering intensity were calculated.

Background [166Ho]Ho-acetylacetonate-poly(L-lactic acid) microspheres were used in radioembolization of liver malignancies by intra-arterial administration. The primary aim of this study was to assess the stability and biodistribution of these microspheres. Materials and methods Peripheral blood and urine samples were obtained from two clinical studies. Patient and in vitro experiment samples were analyzed using inductively coupled plasma mass spectrometry (ICP-MS), gamma-ray spectroscopy, light microscopy, Coulter particle counting, and high performance liquid chromatography (HPLC). Results The median percentage holmium compared to the total amount injected into the hepatic artery was 0.19% (range 0.08–2.8%) and 0.32% (range 0.03–1.8%) in the 1 h blood plasma and 24 h urine, respectively. Both the blood plasma and urine were correlated with the neutron irradiation exposure required for [166Ho]Ho-AcAc-PLLA microsphere production (ρ = 0.616, p = 0.002). After a temporary interruption of the phase 2 clinical study, the resuspension medium was replaced to precipitate [166Ho]Ho3+ pre-administration using phosphate. The in vitro near-maximum neutron irradiation experiments showed significant [166Ho]Ho-AcAc-PLLA microsphere damage. Conclusion The amount of holmium in the peripheral blood and urine samples after [166Ho]Ho-AcAc-PLLA microsphere intrahepatic infusion was low. A further decrease was observed after reformulation of the resuspension solution but minimization of production damage is necessary.

KTiOPO4:Ho and KTiOPO4:Er single crystals are grown by a top-seeded solution growth method from potassium phosphate and MoO3 flux. The crystalline phase, packing structure and chemical composition of the crystals are analyzed by X-ray diffraction (XRD), energy dispersive spectrum (EDS). The doping of Ho and Er induced strain in the crystal is determined from Williamson–Hall relation. The bonding between titanium and oxygen of Ho and Er doping in the KTP crystal is changing the pseudo-symmetrical deviation in the lattice. The bonding of O and Ti decreases with doping Ho and Er and Ti3+ content in the crystal. The bonding, distortion of the TiO6-TiO6 chain and change in inter-atomic distances by erbium and holmium doping are assessed by Raman spectroscopy and low temperature ESR spectroscopy which evidences the low concentration of Ti3+ presence in the crystal. The KTiOPO4:Ho and KTiOPO4:Er single crystal shows second harmonic generation properties which shows that the efficiency ratio of ηKTiOPO4:Ho/η KTiOPO4 = 0.63 and ηKTiOPO4:Er/η KTiOPO4 = 0.80.

Combustion synthesized nanocrystalline holmium (Ho) doped yttrium oxide (Y2O3) was irradiated with gamma (γ) rays, 100 MeV silicon (Si8+) and 150 MeV gold (Au9+) ions to investigate the thermoluminescent (TL) properties for dosimeter applications. No changes were observed in the crystal structure of the material even after it was exposed to the high energy ion beams. The sizes of the crystallites, however, decreased. The TL glow curves of the γ-irradiated samples showed a prominent peak at 419 K with a shoulder at 493 K. TL glow curves for the Si8+ and Au9+ ion irradiated samples showed maximum peaks centred at 407 K, 660 K and 465, 509 and 640 K. The TL glow curve peak intensity of the γ-irradiated samples increased upto a 3 kGy dose and then it decreased with a further increase in the dose but the position of the glow curve peak's temperature remained constant. The TL intensity of the Si8+ and Au9+ ions irradiated samples increased upto 5 × 1010 ions cm−2 of the fluence and then it decreased with a further increase in ion fluence. The glow curves' shapes were different from that of the gamma irradiated samples, because of different TL mechanisms involved. The TL curves were deconvoluted to calculate the kinetic parameters. The activation energy and the frequency factor are in the range of 0.90 eV–1.40 eV and 7.21 × 109 − 5.83 × 1014 s−1, respectively. The synthesized material exhibited longer TL lifetimes under the 150 MeV Au9+ ions to that of the 100 MeV Si8+ and gamma irradiated samples. The results demonstrated that Y2O3:Ho3+ possesses a high resistance to defect formation even at high electronic energy depositions. After swift heavy ion (SHI) irradiation the samples exhibited radiation resistance.

This study demonstrates the formation of barrier-type anodic films in a phosphate buffer (pH 8.4) on thermally evaporated aluminium-holmium alloys covering a 2.0–12.0 at.% Ho compositional spread. Scanning x-ray diffraction and scanning electron microscopy reveal that structure and morphology of the parent alloys library drastically change above 6.5 at.% Ho. Anodic films were formed when the as-evaporated alloys were stepwise anodized potentiodynamically to a maximum of 10 V in phosphate buffer regardless of film composition and morphology. Simultaneous in-situ electrochemical impedance spectroscopy discloses a good co-relation between film thickness and formation factor with the composition and morphology of parent alloys, suggesting a strong influence of holmium concentration on the structure, morphology of parent alloys as well as on the dielectric properties of resulting anodic films. Inductively coupled plasma optical emission spectroscopy measurements allowed a quantitative determination of the dissolved species during anodization.

Based on the 2,2′-bipyridine-5,5′-dicarboxylic acid ligand (H2bpdc), a new metal–organic framework using holmium as the coordinating metal site was synthesized through a solvothermal reaction. The 3D compound {[Ho2(bpdc)3(DMF)2]·2(DMF)}n (1) was characterized by single crystal X-ray diffraction, FTIR, TGA and PXRD. The coordination between H2bpdc, the solvent, and holmium (CN = 7) allows for the construction of a MOF containing potentially free metal sites and uncoordinated N-donor sites. These features make this MOF an attractive holmium carrier for radiotherapeutic applications.

An optical temperature sensor suitable for label free liquid sensing has been designed and characterized. The sensor combines the photochemical stability of rare earth doped glasses and the high sensitivity of interferometric resonators. It is formed by a planar Fabry-Perot (FP) microcavity filled with the liquid to be monitored. A Ho3+ doped tapered optical fiber has been placed inside the microcavity surrounded by the fluid medium. An external laser is focused on the optical fiber inside the cavity to induce the luminescence of the Ho3+ ions, which couples to the FP optical resonances. The spectral position of the FP resonances is highly sensitive to the refractive index of the cavity medium. A second laser is co-aligned with the first one to locally heat the liquid medium around the optical fiber. An average blue shift of the FP resonances around 32 pm/°C is measured. The limit of detection of the laser induced heating of the liquid medium is about 0.3 °C in the biological temperature range. Alternatively, a hot-plate is used to heat the system. Interestingly, a red shift of the FP modes is observed with 75 pm/°C dependence and 0.12 °C limit of detection features.

In order to obtain high quality white light, we synthesized yellow phosphors by doping europium and other lanthanoids such as holmium and lutetium. We successfully obtained yellow phosphors with green emissions with a wavelength of 510 nm for Li2SrSiO4 by co-doping europium and holmium. Unlike single doping of europium, a lower reduction temperature seemed to be preferable. When we simulated the chromaticity of white light at 5000 K, achieved by mixing blue light, which was used for excitation, and this phosphor, it resulted in better quality than commercially available products.