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This work discloses a newly-discovered Cu8−xGe(S, Te)6 argyrodite stabilizing in a high-symmetry cubic phase in the entire low-to-mid temperature region (250–700 K).

Dietary preparation protocols are an effective means to suppress physiological myocardialThe patients were divided into four groups to undergo different preparatory protocols as follows: a minimum 15-hours fast alone, two meals of high-fat, low-carbohydrate diet (HFLCD), two meals of high-animal-protein, low-carbohydrate diet (HAPLCD), and two meals of high-plant-based-protein, low-carbohydrate diet (HPPLCD). Boxed meals were prepared to meet the required carbohydrate restrictions. Myocardial SUVThe average myocardial SUVUsing the predesigned boxed meals based on carbohydrate restriction, HFLCD, HAPLCD, and HPPLCD can be administered to patients with different dietary needs, while providing a substantial reduction in physiological myocardial FDG uptake.

The self-attenuation of a patient’s body is an important factor in nuclear medicine for designing radiation shielding. Taiwanese reference man (TRM) and Taiwanese reference woman (TRW) were constructed to simulate the body dose rate constant and the effective body absorption factor for 18F-FDG, 131I-NaI and 99mTc-MIBI using the Monte Carlo technique. For TRM, the maximum body dose rate constants for 18F-FDG, 131I-NaI and 99mTc-MIBI were 1.26 × 10−1, 4.89 × 10−2 and 1.76 × 10−2 mSv-m2/GBq-h, respectively, at heights of 110, 110 and 100 cm. For TRW, the results were 1.23 × 10−1, 4.75 × 10−2 and 1.68 × 10−2 mSv-m2/GBq-h at heights of 100, 100 and 90 cm. The effective body absorption factors were 32.6, 36.7 and 46.2% for TRM and 34.2, 38.5 and 48.6% for TRW. Regional reference phantoms along with the derived body dose rate constant and effective body absorption factor should be used for determining regulatory secondary standards in nuclear medicine.

Single-crystalline tin-selenide (SnSe) has emerged as a high-performance and eco-friendly alternative to the lead-chalcogens often used in mid-temperature thermoelectric (TE) generators. At high temperature >800 K, the phase transition from Pnma to Cmcm causes a significant rise in the TE figure-of-merit (zT) curve. Conversely, the SnSe TE requires a booster at low temperatures, which allows broader applicability from a device perspective. Herein, a synergy of Cu alloy and Ag-coating is realized through a sequential multi-step synthesis, designed to combine different metal deposition effects. Single-crystalline (Cu2Se)x(SnSe)1−x alloys grown by the Bridgman method were then coated with a thin Ag layer by radio frequency (RF) sputtering, and the interlayer epitaxial film was observed via electric-current assisted sintering (ECAS). Consequently, the thin Ag-coating improves the electrical conductivity (σ) and reduces the thermal conductivity (κ) for (Cu2Se)0.005(SnSe)0.995+Ag alloy, increasing the zT curve at close to room temperature (373 K). The incorporation of multistep addition by ECAS enables tuning of the overall solubility of the alloy, which opens a new avenue to optimize TE performance in anisotropic 2D materials.

Normalized glandular dose (DgN) coefficients obtained using homogeneous breast phantoms are commonly used in breast dosimetry for mammography. However, glandular tissue is heterogeneously distributed in the breast. This study aimed to construct three-layer heterogeneous mammographic phantoms (THEPs) to examine the effect of glandular distribution on DgN coefficient. Each layer of THEPs was set to 25%, 50%, or 75% glandular fraction to emulate heterogeneous glandular distribution. Monte Carlo simulation was performed to attain mean glandular dose (MGD) and air kerma at 22–36 kVp and W/Al, W/Rh, and W/Ag target–filter combinations. The heterogeneous DgN coefficient was calculated as functions of the mean glandular fraction (MGF), breast thickness, tube voltage, and half-value layer. At 50% MGF, the heterogeneous DgN coefficients for W/Al, W/Rh, and W/Ag differed by 40.3%, 36.7%, and 31.2%. At 9-cm breast thickness, the DgN values of superior and inferior glandular distributions were 25.4% higher and 29.2% lower than those of uniform distribution. The proposed THEPs can be integrated with conventional breast dosimetry to consider the heterogeneous glandular distribution in clinical practice.

We revisit the well-established Bi2Te3 via phase diagram engineering. Along with a phase diagram in hand, it is realized that the solubility of Ga in Bi2Te3 is coincident with the p–n transition zo...

To evaluate the effects of anodization on the friction behavior of beta-titanium (β-Ti) orthodontic archwires in conventional or self-ligating brackets in vitro. β‑Ti archwires (0.018 × 0.025 inch) pre- and postanodization were tested in combination with 0.022-inch stainless steel conventional and self-ligating brackets. The surface composition and oxide thickness of the β‑Ti archwires pre- and postanodization were measured using Auger electron spectroscopy (AES) and transmission electron microscopy (TEM). Detailed surface topography and roughness were assessed using atomic force microscopy (AFM). Surface topographies of the β‑Ti archwires pre- and postanodization were examined using scanning electron microscopy (SEM). Friction was measured using a universal testing machine; the data were statistically analyzed. Postanodization, the identified titanium oxide layer on the surface of the β‑Ti archwires increased in thickness from 10 to 100 nm; at the same time, the values for surface roughness were significantly reduced by half (p

Most high-entropy alloys and medium-entropy alloys (MEAs) possess outstanding mechanical properties. In this study, a series of lightweight nonequiatomic Al50–Ti–Cr–Mn–V MEAs with a dual phase were produced through arc melting and drop casting. These cast alloys were composed of body-centered cubic and face-centered cubic phases. The density of all investigated MEAs was less than 5 g/cm3 in order to meet energy and transportation industry requirements. The effect of each element on the microstructure evolution and mechanical properties of these MEAs was investigated. All the MEAs demonstrated outstanding compressive strength, with no fractures observed after a compressive strain of 20%. Following the fine-tuning of the alloy composition, the Al50Ti20Cr10Mn15V5 MEA exhibited the most compressive strength (~1800 MPa) and ductility (~34%). A significant improvement in the mechanical compressive properties was achieved (strength of ~2000 MPa, strain of ~40%) after annealing (at 1000 °C for 0.5 h) and oil-quenching. With its extremely high specific compressive strength (452 MPa·g/cm3) and ductility, the lightweight Al50Ti20Cr10Mn15V5 MEA demonstrates good potential for energy or transportation applications in the future.

Most medium entropy alloys (MEAs) exhibit excellent mechanical properties, but their applications are limited because of their high density. This study explores a series of lightweight nonequiatomic Ti65(AlCrNbV)35-xZrx (x = 3, 5, 7, and 10) MEAs with a low density, high strength, and high ductility. To achieve solid solution strengthening, Zr with a large atomic radius was used. In addition, various thermomechanical treatment parameters were adopted to further improve the MEAs’ mechanical properties. The density of the MEAs was revealed to be approximately 5 g/cm3, indicating that they were lightweight. Through an X-ray diffraction analysis, the MEAs were revealed to have a single body-centered cubic structure not only in the as-cast state but also after thermomechanical treatment. In terms of mechanical properties, all the as-cast MEAs with Zr additions achieved excellent performance (>1000 MPa tensile yield strength and 20% tensile ductility). In addition, hot rolling effectively eliminated the defects of the MEAs; under a given yield strength, hot-rolled MEAs exhibited superior ductility relative to non-hot-rolled MEAs. Overall, the Ti65(AlCrNbV)28Zr7 MEAs exhibited an optimum combination of mechanical properties (yield strength > 1200 MPa, plastic strain > 15%) after undergoing hot rolling 50%, cold rolling 70%, and rapid annealing for 30 to 50 s (at a temperature of approximately 850 °C) with a heating rate of 15 K/s. With their extremely high specific yield strength (264 MPa·g/cm3) and high ductility (22%), the Ti65(AlCrNbV)28Zr7 MEAs demonstrate considerable potential for energy and transportation applications.

We prepared amorphous indium–gallium–zinc oxide (a-IGZO) thin films with various Ga content ratios and investigated their feasibility as the active channel layers of top-gate thin-film transistors (TFT). First, the 2-inch IGZO sputtering targets with stoichiometric ratios of InGaZn2O5, InGaZnO4, and InGa2ZnO5.5 were fabricated using In2O3, Ga2O3, and ZnO oxide powders as raw materials via sintering treatments at temperatures ranging from 900 °C to 1300 °C for 6 h or 8 h. X-ray diffraction analysis indicated that the InGaZn2O5 and InGaZnO4 targets are single-phase structures whereas the InGa2ZnO5.5 target is a two-phase structure. Hall effect measurement indicated that the a-InGaZn2O5 and a-InGaZnO4 layers possess a carrier concentration (N) of about 1019 cm−3 and a resistivity (ρ) of about 10−2 Ω·cm; however, the N of the a-InGa2ZnO5.5 layer is only 1017 cm−3, and the ρ is about 1 to 4 Ω·cm. Moreover, the a-InGaZn2O5 layer exhibited the highest Hall-effect mobility (μHall) of 21.17 cm2·V−1·sec−1. This indicated that the impedance of Ga3+ ions to carrier migration is the main factor affecting the electrical properties of a-IGZO layers. Ga content in the a-IGZO channel similarly affects the performance of the TFT devices prepared in this study. The annealing at 300 °C for 1 h in an ambient atmosphere was found to significantly improve the electrical properties of the TFT devices. The best performance was observed in the a-InGaZnO4 TFT sample subjected to post-annealing at 300 °C with Vth = −0.85 V, μFE = 8.46 cm2, V−1·sec−1, SS = 2.31, V·decade−1, and Ion/Ioff = 2.9 × 104.

Zn4Sb3-based compounds constitute a lead-free material family with a best thermoelectric figure of merit (zT) in the midtemperature range. Unlike being a stoichiometric compound, the mutual solubil...

On-board cone-beam computed tomography (CBCT) was used to scan the N-isopropylacrylamide (NIPAM) gel dosimeter. A dose-response curve from 1 to 12 Gy was created. The dose profile and depth dose curve were measured, and the dose distribution acquired from CBCT was then compared with that obtained from a treatment planning system (TPS). The linearity of the dose-response curve obtained by CBCT scanning of the NIPAM gel was 0.985. The mean percent standard deviation of various doses was 12.8%. A 12- to 24-h post-irradiation time was required to achieve stable CBCT readouts. Both dose profile and depth dose were in agreement with the results of TPS. The dose difference at the isocenter between CBCT and TPS was 3.8%. The gamma evaluation under the conditions of 5% dose difference and 5 mm distance-to-agreement was performed with the pass rate of 92.6%. These results indicate that an on-board CBCT can be used for scanning gel dosimeters in clinical radiotherapy.

Purpose Polymer gel dosimeters provide three-dimensional absorbed dose information and have gradually become a popular tool for quality assurance in radiotherapy. This study aims to incorporate iodine into the MAGAT-based gel as radiation sensitizer and investigate whether it can be used to measure the radiation dose and slice thickness for CT scans. Methods The nMAGAT(I) gel was doped with 0.03, 0.05, and 0.07-M iodine. The absorbed dose was delivered using a CT scanner (Alexion 16, Toshiba Medical Systems, Japan) with tube voltages of 80, 100, 120, and 135 kVp. The irradiated nMAGAT(I) gel was read using a cone beam optical CT scanner to produce dose-response curves. The nMAGAT(I) gel was used to obtain the slice sensitivity profile (SSP) and the CT dose index (CTDI) for quality assurance of CT scans. Results The 0.07-M iodine-doped nMAGAT(I) gel exhibited maximum sensitivity with the dose enhancement ratio of 2.12. The gel was chemically stable 24 h after its preparation, and the polymerization process was completed 24–48 h after the irradiation. For CT quality assurance, the full width at half maximum measured by the nMAGAT(I) gel matched the nominal slice thickness of CT. The CTDI at center, CTDI at peripheral, and weighted CTDI obtained by the nMAGAT(I) gel differed from those obtained by the ionization chamber by −4.2%, 3.1%, and 0.7%, respectively. Conclusions The nMAGAT(I) gel can be used to assess radiation doses and slice thickness in CT scans, thus rendering it a potential quality assurance tool for CT and other radiological diagnostic applications.

Hydrogen evolution reaction (HER) from water electrolysis is a promising route for hydrogen fuel production. However, an effective conversion technology from distributed energy resources, such as solar energy and thermal energy, to hydrogen energy is still a challenging research. Here, earth-abundant and multifunctional Ni nanosheets array as electrocatalysts and light absorption layer integrated thermoelectric (TE) device for overall water splitting was proposed. Instead of the traditional power source, the output voltage from thermoelectric (TE) device was directly used for water splitting. More importantly, the structural, photothermal transformation and electrocatalytic characterizations confirmed that the earth-abundant and multifunctional Ni nanosheets array grown on the hot side of TE device was not only as an efficient photothermal conversion layer for providing temperature difference (ΔT) of TE, but also as an active electrocatalysts for HER. The Electrolyzer-TE hybrid devices were designed for overall water splitting in a two-electrode configuration, which possessed high hydrogen production rate of 1.818 mmol/h and oxygen production rate of 0.912 mmol/h. The proposed integrative TE device herein offered great advantages in terms of designing the overall water splitting system, which are helpful for its practical applications for utilization of solar thermal and waste heat.

Digital mammography has become a first-line diagnostic tool for clinical breast cancer screening due to its high sensitivity and specificity. Mammographic compression force is closely associated with image quality and patient comfort. Therefore, optimizing breast compression parameters is essential. Subjects were recruited for digital mammography and breast magnetic resonance imaging (MRI) within a month. Breast MRI images were used to calculate breast volume and volumetric breast density (VBD) and construct finite element models. Finite element analysis was performed to simulate breast compression. Simulated compressed breast thickness (CBT) was compared with clinical CBT and the relationships between compression force, CBT, breast volume, and VBD were established. Simulated CBT had a good linear correlation with the clinical CBT (R2 = 0.9433) at the clinical compression force. At 10, 12, 14, and 16 daN, the mean simulated CBT of the breast models was 5.67, 5.13, 4.66, and 4.26 cm, respectively. Simulated CBT was positively correlated with breast volume (r > 0.868) and negatively correlated with VBD (r < –0.338). The results of this study provides a subject-specific and evidence-based suggestion of mammographic compression force for radiographers considering image quality and patient comfort.

To evaluate the effects of anodization on the friction behavior of beta-titanium (β-Ti) orthodontic archwires in conventional or self-ligating brackets in vitro.β‑Ti archwires (0.018 × 0.025 inch) pre- and postanodization were tested in combination with 0.022-inch stainless steel conventional and self-ligating brackets. The surface composition and oxide thickness of the β‑Ti archwires pre- and postanodization were measured using Auger electron spectroscopy (AES) and transmission electron microscopy (TEM). Detailed surface topography and roughness were assessed using atomic force microscopy (AFM). Surface topographies of the β‑Ti archwires pre- and postanodization were examined using scanning electron microscopy (SEM). Friction was measured using a universal testing machine; the data were statistically analyzed.Postanodization, the identified titanium oxide layer on the surface of the β‑Ti archwires increased in thickness from 10 to 100 nm; at the same time, the values for surface roughness were significantly reduced by half (p 0.001). The archwire surfaces post anodization were harder and had fewer scratches after the friction test. Anodization significantly reduced 23.77% of the static (p 0.01) and 25.61% of the kinetic (p 0.001) friction of the β‑Ti archwires in conventional brackets, while it significantly reduced 85.71% of the static and 84.38% of the kinetic friction (p 0.01) in self-ligating brackets.Anodization reduced the β‑Ti archwire friction, which was particularly more effective in combination with self-ligating brackets. The friction reduction via anodization could be attributed to the increased thickness, surface hardness, and decreased surface roughness of the titanium oxide layer.ZIEL: Untersucht werden sollten die Auswirkungen einer Eloxierung auf das Reibungsverhalten von kieferorthopädischen Bogendrähten aus β‑Titan (β-Ti) in konventionellen bzw. selbstligierenden Brackets in vitro.β‑Ti-Bögen (0,018 × 0,02 Inch) vor und nach der Eloxierung wurden in Kombination mit konventionellen und selbstligierenden Brackets aus Edelstahl (0,022 Inch) getestet. Die Oberflächenzusammensetzung und die Oxiddicke der β‑Ti-Bögen vor und nach der Eloxierung wurden mit Auger-Elektronenspektroskopie (AES) und Transmissionselektronenmikroskopie (TEM) bestimmt. Die detaillierte Oberflächentopografie und -rauheit wurde mittels Rasterkraftmikroskopie (AFM) bewertet. Die Oberflächentopografien der β‑Ti-Bögen vor und nach der Eloxierung wurden mit dem Rasterelektronenmikroskop (REM) untersucht. Die Friktion wurde mit einer Universalprüfmaschine ermittelt; die Daten wurden statistisch ausgewertet.Nach der Eloxierung nahm die Dicke der identifizierten Titanoxidschicht auf der Oberfläche der β‑Ti-Bögen von 10 auf 100 nm zu; gleichzeitig wurden die Werte für die Oberflächenrauheit signifikant um die Hälfte reduziert (p 0,001). Nach der Eloxierung waren die Oberflächen der Bögen härter und hatten weniger Kratzer nach dem Friktionstest. Die Eloxierung reduzierte signifikant 23,77% der statischen (p 0,01) und 25,61 % der kinetischen (p 0,001) Reibung der β‑Ti-Bögen in konventionellen Brackets, während sie signifikant 85,71 % der statischen und 84,38 % der kinetischen Reibung (p 0,01) in selbstligierenden Brackets reduzierte.Die Eloxierung kann die Friktion des β‑Ti-Bogens reduzieren, besonders effektiv in Kombination mit selbstligierenden Brackets. Die Verringerung der Friktion durch die Eloxierung könnte auf die Zunahme der Dicke und der Oberflächenhärte sowie die Verringerung der Oberflächenrauhigkeit der Titanoxidschicht zurückzuführen sein.

Microstructure engineering fulfilled by phase transformation elicits the reduced thermal conductivity κ in thermoelectric materials. We demonstrate that the multiscale hierarchical twinning structure could exist in the GeTe alloys as the phase transformation from cubic β-GeTe to rhombohedral α-GeTe is manipulated by two-step cooling. The coexistence of nanoscale and microscale herringbone structures yields the low-lying κ, attributing to the reorientation of martensitic variants and pile-up of martensitic twinning. Dilute dopants of Cu and Bi/Sb further suppresses hole carrier concentration nH to the order of 1020 cm−3, leading to the enhanced power factor PF = S2ρ−1 of α-GeTe. Meanwhile, the phase diagram engineering probes the solubility limit of Cu in the single-phase GeTe, diminishing the formation of undesired impurity phases. These strategies boost the peak zT value to 1.5 at 698 K in the light-doped Bi0.01Cu0.01Ge0.98Te alloy. The multiscale twin hierarchy and carrier optimization synergistically enhance the thermoelectric performance of GeTe-based alloys that provide a new chapter in search of green energy resources out from phase change materials.

A novel lightweight Al-Ti-Cr-Mn-V medium-entropy alloy (MEA) system was developed using a nonequiatiomic approach and alloys were produced through arc melting and drop casting. These alloys comprised a body-centered cubic (BCC) and face-centered cubic (FCC) dual phase with a density of approximately 4.5 g/cm3. However, the fraction of the BCC phase and morphology of the FCC phase can be controlled by incorporating other elements. The results of compression tests indicated that these Al-Ti-Cr-Mn-V alloys exhibited a prominent compression strength (~1940 MPa) and ductility (~30%). Moreover, homogenized samples maintained a high compression strength of 1900 MPa and similar ductility (30%). Due to the high specific compressive strength (0.433 GPa·g/cm3) and excellent combination of strength and ductility, the cast lightweight Al-Ti-Cr-Mn-V MEAs are a promising alloy system for application in transportation and energy industries.