Tm Films Research Articles

Degree of Concordance Between Cone Beam Computerized Tomography (Cbct) And 2d Digital Radiography System Used for Caries Diagnosis: An Observational Study

Background: Caries is a disease with a high prevalence, which may be due to the lack of adequate methods for its early diagnosis, becomes difficult to detect initial caries lesions in posterior teeth due to the occlusal anatomy of these and because on many occasions they start in the interproximal zone below the contact areas. Different techniques have been used for the diagnosis of caries, such as visual-tactile inspection, radiography, tomography, and transillumination, but none of them seems to have complete sensitivity or specificity. Aim: This study aims to establish the degree of agreement between radiographic diagnosis with 2D intraoral digital radiography in relation to cone beam computed tomography in extracted carious and healthy posterior teeth, practicing the CariesCare International ™ practical guide as a reference. Materials and Methods: A total number of 117 teeth with or without carious lesions were selected. Digital images of all teeth were obtained from 2D digital radiographs (instrumentarium ™ films) obtained with Kavo focus equipment and CBCT scanner I-CAT ™ model 1719, ISI (imaging science international), Pennsylvania (blue sky plan 4 software). Observers evaluated the images for the detection of carious lesions. The sensitivity and specificity ratio between the systems was determined using the area under the curve statistical tool ROC (Receiver Operating Characteristic). For the statistical analysis, the statistical program STATA IC/16 was used, in which the calculation of absolute and relative frequencies for each category of CariesCare international in CBCT and radiography was performed, in addition to the Friedman and post-hoc Wilcoxon test by pairs; the distribution according to the classification of CariesCare international was contrasted between the CBCT slices. The calculation of weighted Kappa and dichotomous Kappa and the calculation of validity (sensitivity and specificity) and prediction (predictive values and predictive ratios) were performed. The distribution according to CariesCare international classification was contrasted between the CBCT slices. Results: The results of the present study confirm that diagnosis of caries with the 2D digital radiographic method, initial caries lesions tend to go undetected relative to CBCT. Conclusion: 2D digital radiographs showed low sensitivity for caries detection and high specificity relative to CBCT for caries lesions in vitro. Diagnosis with 2D digital Rx is considered non-discriminative in identifying initial caries lesions.

3D-printed antioxidant antibacterial carboxymethyl cellulose/ε-polylysine hydrogel promoted skin wound repair

Developing a wound dressing for the treatment of large and irregular-shaped wounds remains a great challenge. Herein we developed novel printable bionic hydrogels with antibacterial and antioxidant properties which could effectively overcome the challenge by inhibiting inflammation and accelerating wound healing. The CMC/PL (CP) hydrogels were customized with glycidyl methacrylate (GMA) modified carboxymethyl cellulose (CMC) and ε-polylysine (ε-PL) via ultraviolet (UV) light polymerization using a 3D printer. Except for the high compression modulus (238 kPa), stable rheological properties, and effective degradability, these CP hydrogels also had an excellent inhibitory effect (95%) on both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Remarkably, CP hydrogels could remove the excessive reactive oxygen species (ROS) and protect the fibroblasts from damage. Compared with the commercial dressing (Tegaderm ™ film), CP hydrogels showed a better ability to increase the expression of VEGF and CD31, accelerate granulation tissue regeneration, and promote wound healing. This work provides a new strategy to fabricate on-demand multi-functional hydrogels in the field of skin tissue engineering.

Laser operation of cleaved single-crystal plates and films of Tm:KY(MoO4)2.

We report on the crystal growth, spectroscopy and first laser operation of a novel double molybdate compound - Tm:KY(MoO4)2. This orthorhombic (sp. gr. Pbna) crystal exhibits strong anisotropy of the spectroscopic properties due to its layered structure. The maximum stimulated emission cross-section for the 3F4 → 3H6 transition is 2.70×10-20 cm2 at 1856nm with a bandwidth of >110 nm (for E || b). The lifetime of the 3F4 state is 2.29 ms. Crystalline films and plates (thickness down to 70 µm) of high optical quality are obtained by mechanical cleavage along the (100) plane. Continuous-wave diode-pumped laser operation is achieved in such thin films and plates yielding a maximum output power of 0.88 W at ∼1.9 µm with a slope efficiency of 65.8% and a linearly polarized laser output. Vibronic lasing is demonstrated at ∼2.06 µm. Tm:KY(MoO4)2 is promising for microchip and thin-disk lasers.

Structure and magnetism of Tm atoms and monolayers on W(110)

e pattern due to the overlap with the rectangular W(110) substrate. Monolayer as well as isolated Tm adatoms on W present a trivalent ground-state electronic configuration, contrary to divalent gas phase Tm and weakly coordinated atoms in quench-condensed Tm films. Ligand field multiplet simulations of the x-ray absorption spectra further show that Tm has a |J = 6,Jz =± 5� electronic ground state separated by a few meV from the next lowest substates |J = 6,Jz =± 4� and |J = 6,Jz =± 6� . Accordingly, both the Tm atoms and monolayer films exhibit large spin and orbital moments with out-of-plane uniaxial magnetic anisotropy. X-ray magnetic dichroism measurements as a function of temperature show that the Tm monolayers develop antiferromagnetic correlations at about 50 K. The triangular structure of the Tm lattice suggests the presence of significant magnetic frustration in this system, which may lead to either a noncollinear staggered spin structure or intrinsic disorder.

WE-F-16A-06: Using 3D Printers to Create Complex Phantoms for Dose Verification, Quality Assurance, and Treatment Planning System Commissioning in Radiotherapy

Purpose: To use 3D printers to design and construct complex geometrical phantoms for commissioning treatment planning systems, dose calculation algorithms, quality assurance (QA), dose delivery, and patient dose verifications. Methods: In radiotherapy, complex geometrical phantoms are often required for dose verification, dose delivery and calculation algorithm validation. Presently, fabrication of customized phantoms is limited due to time, expense and challenges in machining of complex shapes. In this work, we designed and utilized 3D printers to fabricate two phantoms for QA purposes. One phantom includes hills and valleys (HV) for verification of intensity modulated radiotherapy for photons, and protons (IMRT and IMPT). The other phantom includes cylindrical cavities (CC) of various sizes for dose verification of inhomogeneities. We evaluated the HV phantoms for an IMPT beam, and the CC phantom to study various inhomogeneity configurations using photon, electron, and proton beams. Gafcromic ™ films were used to quantify the dose distributions delivered to the phantoms. Results: The HV phantom has dimensions of 12 cm × 12 cm and consists of one row and one column of five peaks with heights ranging from 2 to 5 cm. The CC phantom has a size 10 cm × 14 cm and includes 6 cylindrical cavities with length of 7.2 cm and diameters ranging from 0.6 to 1.2 cm. The IMPT evaluation using the HV phantom shows good agreement as compared to the dose distribution calculated with treatment planning system. The CC phantom also shows reasonable agreements for using different algorithms for each beam modalities. Conclusion: 3D printers with submillimiter resolutions are capable of printing complex phantoms for dose verification and QA in radiotherapy. As printing costs decrease and the technology becomes widely available, phantom design and construction will be readily available to any clinic for testing geometries that were not previously feasible.

Luminescent and scintillation properties of YAG:Tm and YAG:Ce,Tm single crystalline films

The paper is dedicated to studying the luminescent and scintillation properties of the single crystalline films (SCF) of Tm and Tm–Ce doped Y3Al5O12 garnets grown by the liquid phase epitaxy method. We have found that the effective Tm→Ce energy transfer is observed in YAG:Ce,Tm SCF. As a result of such transfer, the scintillation light yield of YAG:Ce,Tm SCF under α-particles excitation can be large in comparison with YAG:Ce SCF counterpart.

Inherently Photohealable and Thermal Shape-Memory Polydisulfide Networks.

Structurally dynamic polydisulfide networks that inherently exhibit both shape-memory and healable properties have been synthesized. These materials are semicrystalline, covalently cross-linked network polymers and as such exhibit thermal shape-memory properties. Upon heating above its melting temperature (Tm) films of the material can be deformed by a force. Subsequent cooling and removal of the force result in the material being "fixed" in this strained temporary shape through a combination of crystallinity and covalent cross-links until it is exposed to temperatures above the Tm at which point it recovers to its remembered processed shape. The incorporation of disulfide bonds, which become dynamic/reversible upon exposure to light or elevated temperatures, into these networks results in them being structurally dynamic upon exposure to the appropriate stimulus. Thus, by activating this disulfide exchange, the network reorganizes, and the material can flow and exhibit healable properties. Furthermore, exposure to light also allows the film's permanent "remembered" shape to be reprogrammed. Shape-memory experiments on these films show high degrees of both fixing and recovery (>95%), and photohealing experiments showed that the films were able to recover from a scratch whose depth is approximately half the thickness of the film. Using a combination of the thermal shape-memory behavior followed by photohealing allows wide scratches to also be efficiently healed.

Interpreting Disturbed Minds: Donald Davidson and The White Ribbon

Thomas Elsaesser claims the late Haneke as a director of ‘mind-game’ films, but his diagnosis of the appeal of such films fails to account for The White Ribbon . In this paper, I draw on the theory of radical interpretation developed by American philosopher Donald Davidson to uncover the film’s power. I argue that the focus on charity in Davidson’s account of the conditions under which an interpreter is able to find a foreign community intelligible illuminates the exquisite discomfort the spectator experiences as she begins to understand the disturbed community that the film portrays. In addition, the film exposes that Davidson’s transcendental argument that language is a condition of mindedness ought to be extended along emotional and moral dimensions. We should not only hold that every rational mind is a language-user, but that every rational mind is an appropriate language-user, so as to account for minds that have true, justified beliefs but which are, nevertheless, disturbed.

Neutralization of bitis parviocula (Ethiopian mountain adder) venom by the south african institute of medical research (SAIMR) antivenom

The Ethiopian mountain adder (Bitis parviocula) is a viperid known only from a few locations in southwestern Ethiopia. a total of 30 µg of B. arietans and B. parviocula venoms were run on a 10-20% Tricine gel. To assay lethality dose fifty (LD50), five groups of eight mice for each venom were used. Hemorrhagic activity for crude venom was tested. Fibrinogenolytic activity of crude venom was measured using (2.5 mg/mL) of fibrinogen solution and (0.03 mg/mL) of crude venom. Gelatinase activity of the venom was tested on a Kodak X-OMAT TM film. Crude venoms of B. parviocula and B. arietans were tested for their abilities to affect clotting time, clotting rate and platelet function on whole human blood. The (SAIMR) antivenom was confirmed in this study to neutralize the lethal activity of venom from Bitis parviocula. The ED50s of SAIMR antivenom on B. parviocula and B. arietans neutralized half of 18.2 and 66.7 mg of venom, respectively. The hemorrhagic activities (MHDs) of B. parviocula and B. arietans were 0.88 and 1.7 µg, respectively. Bitis arietans and B. parviocula venoms degradated α and β chains at different times. The γ chains remained unaffected. Bitis parviocula venom did not exhibit gelatinase activity, while B. arietans had a MGD of 6.9 µg. At 3 mg/mL, the crude venoms of B. parviocula and B. arietans did not significantly affect clotting time or clotting rate. The SAIMR antivenom is very effective in neutralizing the venom of B. parviocula and should be considered in treating envenomations by these snakes.

Why Is Touch Sometimes So Touching?: The Phenomenology of Touch in Susan Streitfeld's Female Perversions

The film Female Perversions (1996) has received mixed reviews in newspapers and popular magazines. Critics have made appreciative comments on the powerful feminist message of the film, while many reviews registered frustration at the overuse of vulgarised Freudian psychoanalytic discourses in the film. Apart from those film reviews, however, many viewers have been somehow touched by the film and especially by the last scene, in which Eve physically ‘touches’ a girl’s face—though they do not know exactly why they felta€€the film was so good. The difficulty of discussing the film Female Perversions lies in its contradictory appeal to the audience. While the film calls on the audience—most likely to be either ‘art-film’ fans or ‘professional’ viewers—to participate in the discussion about contemporary sexual politics, it eventually encourages them to suspend such a cerebral way of appreciating the film and to engage emotionally and physically in it as ‘lay’ cinema fans enjoy a nice entertainment movie. This apparently ‘highbrow’ film illuminates the very gap between the sophisticated analytic mode of film-watching and a more sensual and corporeal cinematic experience, and in a very subtle manner it invites us to move from the former mode of filmic experience to the latter. This paper aims to describe in words the film, the audience, and the intertwining of the two as a sensual, material, and corporeal being. For this purpose, this paper focuses on the moments of ‘touch’ in the film, the effect of which plays a crucial role in the subtle shift of the filmic mode mentioned above. Drawing on Merleau-Ponty’s phenomenological reflection on touch, this paper textualises what happens when touch happens in the film, how touch serves to produce the power of the film, and how it works on us when we are watching it.

Transmittance and optical constants of Tm films in the 2.75–1600 eV spectral range

The optical constants of thulium (Tm) films were obtained in the 2.75–1600 eV range from transmittance measurements performed at room temperature. Thin films of Tm were deposited by evaporation in ultrahigh vacuum conditions and their transmittance was measured in situ. Tm films were deposited onto grids coated with a thin, C support film. Transmittance measurements were used to obtain the optical extinction coefficient k of Tm films. The refractive index n of Tm was calculated using the Kramers–Krönig analysis. k data were extrapolated both on the high and the low energy sides by using experimental and calculated extinction coefficient values available in the literature. Tm, similar to other lanthanides, has a low-absorption band below the O2,3 edge onset; the lowest absorption was measured at ∼23 eV. Therefore, Tm is a promising material for filters and multilayer coatings in the energy range below the O2,3 edge in which materials typically have an absorption stronger than away. Good consistency of the data was obtained through f and inertial sum rules.

The effect of growth temperature on the luminescence and structural properties of GaN:Tm films grown by gas-source MBE

During molecular beam epitaxy of GaN:Tm films, substrate temperature strongly influences the rare earth incorporation, surface morphology and luminescence spectrum. The Tm incorporation into films grown between 730 and 830 °C was estimated by wavelength-dispersive X-ray (WDX) spectroscopy. Comparative WDX, atomic force microscopy (AFM) and cathodoluminescence (CL) mappings reveal that at an optimal growth temperature between 775 and 780 °C, a high Tm content (∼2.2 at%) and a smooth surface morphology can be obtained, leading to an intense sharp Tm 3+ emission. For lower substrate temperatures, Ga droplets and large (∼8–15 μm) circular pits mar the sample surface; for higher temperatures, the sharp CL lines disappear due to low Tm content (⩽0.8 at%).

Electron penetration depth in amorphous AlN exploiting the luminescence of AlN:Tm/AlN:Ho bilayers

Abstract The penetration depth of electron in amorphous aluminum nitride (AlN) is determined in terms of energy loss per unit length using electron beam in a cathodoluminescence (CL) apparatus. Thin films bilayers of holmium doped aluminum nitride (AlN:Ho) and thulium doped aluminum nitride (AlN:Tm) are deposited on silicon substrates by rf magnetron sputtering method at liquid nitrogen temperatures. The bilayers structure consisted of a 37.8 nm thick AlN:Tm film on the top of a 15.3 nm thick AlN:Ho film. Electron beam of different energies are allowed to penetrate the AlN:Tm/AlN:Ho bilayers film. The spectroscopic properties of AlN:Ho and AlN:Tm, the thickness of the film and the energies of electron beam are used to calculate the penetration depth of electron in amorphous AlN. Electron beam of 2.5 keV energy was able to pass through the 37.8 nm thick AlN:Tm film. The electron penetration depth for AlN is found to be 661.4 MeV/cm.

Iodine Deficiency Induces a Thyroid Stimulating Hormone-Independent Early Phase of Microvascular Reshaping in the Thyroid

Expansion of the thyroid microvasculature is the earliest event during goiter formation, always occurring before thyrocyte proliferation; however, the precise mechanisms governing this physiological angiogenesis are not well understood. Using reverse transcriptase-polymerase chain reaction and immunohistochemistry to measure gene expression and laser Doppler to measure blood flow in an animal model of goitrogenesis, we show that thyroid angiogenesis occurred into two successive phases. The first phase lasted a week and involved vascular activation; this process was thyroid-stimulating hormone (TSH)-independent and was directly triggered by expression of vascular endothelial growth factor (VEGF) by thyrocytes as soon as the intracellular iodine content decreased. This early reaction was followed by an increase in thyroid blood flow and endothelial cell proliferation, both of which were mediated by VEGF and inhibited by VEGF-blocking antibodies. The second, angiogenic, phase was TSH-dependent and was activated as TSH levels increased. This phase involved substantial up-regulation of the major proangiogenic factors VEGF-A, fibroblast growth factor-2, angiopoietin 1, and NG2 as well as their receptors Flk-1/VEGFR2, Flt-1/VEGFR1, and Tie-2. In conclusion, goiter-associated angiogenesis promotes thyroid adaptation to iodine deficiency. Specifically, as soon as the iodine supply is limited, thyrocytes produce proangiogenic signals that elicit early TSH-independent microvascular activation; if iodine deficiency persists, TSH plasma levels increase, triggering the second angiogenic phase that supports thyrocyte proliferation.

Influence of Ge addition on the morphology and properties of TiN thin films deposited by magnetron sputtering

Thin films of TM–X–N (TM stands for early transition metal and X = Si, Al, etc.) are used as protective coatings. The most investigated among the ternary composite systems is Ti–Si–N. The system Ti–Ge–N has been chosen to extend the knowledge about the formation of nanocomposite films. Ti–Ge–N thin films were deposited by reactive magnetron sputtering on Si and WC–Co substrates at T s = 240 °C, from confocal Ti and Ge targets in mixed Ar/N 2 atmosphere. The nitrogen partial pressure and the power on the Ti target were kept constant, while the power on the Ge target was varied in order to obtain various Ge concentrations in the films. No presence of Ge–N bonds was detected, while X-ray photoelectron spectroscopy measurements revealed the presence of Ti–Ge bonds. Transmission Electron Microscopy investigations have shown important changes induced by Ge addition in the morphology and structure of Ti–Ge–N films. Electron Energy-Loss Spectrometry study revealed a significant increase of Ge content at the grain boundaries. The segregation of Ge atoms to the TiN crystallite surface appears to be responsible for limitation of crystal growth and formation of a TiGe y amorphous phase.

Cathodoluminescence and its temperature dependence in Tm‐doped Al x Ga 1– x N thin films

Cathodoluminescent (CL) emission from Tm-doped Al x Ga 1 - x N (Al x Ga 1 - x N:Tm) has been observed with various Al compositions (0 ≤ x ≤ 1). According to CL spectrum from Al 0 . 8 1 G 0 . 1 9 N:Tm film 1 D 2 level-related CLemissions were observed to dominate: the strongest was blue at 464 nm and the next was UV at 369 nm, corresponding to the Tm 1 D 2 → 3 F 4 and 1 D 2 → 3 H 6 transitions, respectively. CL luminance increases with Al composition up to x = 0.8, then decreases for AlN:Tm, which is the same as in EL and PL. Luminance value was measured to be 19.4 cd/m 2 . The corresponding efficiency was 0.012 1m/W under 5 kV bias and 10 μA current flow. Temperature dependent CL from the Al 0 . 8 1 Ga 0 . 1 9 N:Tm film shows that 1 D 2 emission increases with temperature up to room temperature (RT) but 1 I 6 emission becomes quenched upon approaching RT.

Properties of Tm [sbnd]Pt(1 1 1) surface alloys

Formation of surface alloys by annealing of thin Tm layers which were deposited on Pt(1 1 1) are investigated by photoemission and low energy electron diffraction (LEED). In addition, adsorption of CO was studied by temperature programmed desorption (TPD). For deposition of more than a monolayer of Tm, a (2 × 2) LEED pattern forms upon heating the sample to 600 °C. The appearance of the (2 × 2) pattern is assigned to alloy formation (“thick alloy”). The Tm 5p and 4f core levels show shifts of 0.8 eV to lower binding energies upon alloying, while the major Tm 4d multiplet shows a 1.1 eV shift to lower binding energy. These Tm shifts are interpreted to be caused by different coordination in the alloys. The present experiments indicate that the surface of the alloy is Pt enriched. For Tm coverages of less than about one monolayer a modified (1 × 1) LEED pattern is observed (“thin” alloy). The core level shifts as observed for the “thick” alloy is not seen for the “thin” alloy. Finally, the work function of a thick evaporated Tm film was measured to be 3.3 eV.

Characterization of the blue emission of Tm/Er co-implanted GaN

AbstractComparative studies have been carried out on the cathodoluminescence (CL) and photoluminescence (PL) properties of GaN implanted with Tm and GaN co-implanted with Tm and a low concentration of Er. Room temperature CL spectra were acquired in an electron probe microanalyser to investigate the rare earth emission. The room temperature CL intensity exhibits a strong dependence on the annealing temperature of the implanted samples. The results of CL temperature dependence are reported for blue emission (∼ 477 nm) which is due to intra 4f-shell electron transitions (1G4 → 3H6) associated with Tm3+ ions. The 477 nm blue CL emission is enhanced strongly as the annealing temperature increases up to 1200°C. Blue PL emission has also been observed from the sample annealed at 1200°C. To our knowledge, this is the first observation of blue PL emission from Tm implanted GaN samples. Intra-4f transitions from the 1D2 level (∼ 465 nm emission lines) of Tm3+ ions in GaN have been observed in GaN:Tm films at temperatures between 20–200 K. We will discuss the temperature dependent Tm3+ emission in both GaN:Tm,Er and GaN:Tm samples.

Epitaxial phase stabilisation phenomena in rare earth manganites

Using injection, powder-flash and band-flash MOCVD techniques, epitaxial thin films of Nd, Ho, Y, Tm, Dy and Lu manganites were prepared. The formation of high-pressure phase NdMn 7O 12 as a thin surface layer on Pnma Nd 1− x MnO 3+δ ( x∼0.15) in an Nd-deficient system and HoMnO 3, YMnO 3, TmMnO 3 and LuMnO 3 as perovskite phases (known in the bulk only as high-pressure phases) on a LaAlO 3 substrate were observed. The remarkable reduction in the pressure needed for formation of the phases in epitaxial films in comparison with bulk samples is a manifestation of the epitaxial stabilisation discussed in the paper. The details of the crystal and domain structure of the films as observed by X-ray diffraction (XRD), selected-area electron diffraction (SAED) and high-resolution electron microscopy (HREM) techniques are described.

Mechanical properties of He irradiated and annealed AZ-1350 J TM films

The nanoindentation technique is used to measure hardness and Young's modulus in 1.7 μm thick photoresist AZ-1350J TM films deposited on Si wafer and irradiated with He ions at 380 keV and at fluences of 10 13, 10 14 and 10 15 He cm −2 . After irradiation the films have been also submitted to isothermal treatments at 350°C for 6 h. The hardness value of 0.45 GPa for pristine film increases with ion irradiation to 2.3 GPa at the highest fluence. Thermal annealing, after irradiation, produces changes in the hardness behavior: for the lowest fluence the hardness raise from 0.7 to 1.0 GPa and for the highest fluence decreases from 2.3 to 1.8 GPa. The Young's modulus values also follow a similar variation after irradiation and thermal treatment. These results are discussed in terms of the crosslinking and the carbonization produced by irradiation and thermal treatment.