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Innovation is the key and fundamental forces for firms to survive and grow in a competitive environment. The paper aims to examine the correlation between Transformational Leadership (TL) and employees' psychological sources and how they affect organization's Innovation Capability (IC). Structural Equations Modeling (SEM) is utilized to elaborate the relationship among the proposal factors through using survey data gathered from 315 participants of 65 medium and small-sized firms in Vientiane, Laos. The findings show that employees' psychological sources namely optimism and self-efficacy act as mediating roles in the effects of TL on IC. The findings revealed that TL's Idealized Influence (TII) brings employees greater optimistic, while individualized consideration creates a stronger self-efficacy among employees. In addition, it highlighted the extremely important of self-efficacy in stimulating IC compared with optimism's effect. From a practical view, the paper highlights the importance and the need of applying TL style in organization management to actively develop employees' positive psychological capital, and improve IC. The findings of paper also bring deeper understanding and theoretical initiatives that can be applied to clarify the correlation among TL, forms of employees' psychological capital, and IC. [ABSTRACT FROM AUTHOR]

Chalcophile (Ag, Cd, Co, Cu, Mo, Ni, Pb, Se, Tl, Zn) and lithophile (Al, Ba, Ce, Cr, Cs, Fe, La, Li, Mn, Nd, Rb, Sr, V, Y) trace elements (TEs) were determined in kidney, liver and muscle of beaver (Castor canadensis) from a rural watershed in southern Ontario, Canada. To estimate the relative bioavailability of TEs in the landscape, they were also determined in the dissolved (<0.45 μm) fraction of water from the river where the animals were harvested. Concentration ratios (tissue/water) always showed the greatest enrichments for Cd (kidney, 1.1 × 107; liver, 2.4 × 106; muscle, 7.2 × 105), most likely due to the metal binding properties of metallothioneins. Despite its potential toxicity, Tl also showed considerable enrichment: kidney, 4.2 × 104; liver 1.2 × 104; muscle 1.5 × 104. Enrichments of Cs and Rb exceeded those of Tl in all three tissues, suggesting that the chemical similarity of their ionic species (Cs+, Rb+, Tl+) to K+ may be the key to their uptake. Lithophile elements of limited solubility in natural waters (Al, Ce, La, Nd) show moderate enrichments, despite the lack of physiological role. The smallest enrichments were found for Sr and Ba, the two TEs which are most abundant in the river. Of the TEs considered essential for animal nutrition, V was the least enriched in tissue relative to water (liver 19×, kidney, 33× and muscle 28×). Despite the lack of physiological function and absence of any known sources of contamination, Al, Ag, Cd, Ce, Cs, La, Pb, Rb, and Tl, are all enriched in beaver tissue, relative to water, by at least three orders of magnitude, due to natural processes. The widespread abundance of beaver in Canada combined with the growing need to manage their numbers in populated regions offer a unique opportunity for monitoring environmental quality in the riparian zone. Unlabelled Image • beaver (Castor canadensis) were taken from a small, rural watershed in S. Ontario. • 10 chalcophile and 12 lithophile elements were determined using ICP-MS in a clean lab. • liver, kidney and muscle were compared with the dissolved fraction of the river. • Cd showed the greatest concentration ratios (105 – 107) and Sr the lowest ratios (tissue/water) • Ag, Ce, Cs, Pb, Rb, and Tl all yielded concentration ratios > 103 [ABSTRACT FROM AUTHOR]

MgCaSi 2 O 6 polycrystal was synthesized by the devitrification method. The dosimetric characteristics by TL of this prepared polycrystal was investigated. This material exhibits TL peaks at 115, 160, 210, 260 and 280 °C. The dosimetric peak occurs at 260 °C with a well defined glow curve structure. This peak shows a linear dose response. Electron paramagnetic resonance (EPR) studies have been carried out to identify the defect centers responsible for the TL peaks. Two defect centers in the region of g = 2.0 are found. One of the centers (center I) with a g factor equal to 2.0085 is identified as O− -ion and relates with the observed high temperature 250 and 300 °C TL peaks. Additional defect centers with g = 2.0012 (center II) and 1.982 (center III) are due to F+-centers (electron trapped at an oxygen vacancy). Center II and III correlate with the TL peaks at 160 °C and 106 °C, respectively. [ABSTRACT FROM AUTHOR]

Highlights • Caregiving stress (CS) does not predict telomere length (TL) in 1233 adults. • There is no effect modification of CS-TL by sex, age, or relationship to caregiver. • Previously published results linking CS and TL are not replicated in our sample. • These and other recent findings suggest CS is not generally predictive of TL. • However, it is possible that specific types of severe caregiving stress predict TL. Abstract Background Caring for chronically disabled family members is a stressful experience. In turn, psychosocial stress is linked to premature aging. Telomere length (TL) is a plastic genetic trait that is a biomarker of aging, and a possible mechanism linking psychosocial stress and accelerated aging. Methods TL was measured using qPCR method from blood samples in 1233 Filipino adults from Cebu, Philippines. Caregiving was measured as chronicity of care, or the sum total number of years an individual was the primary caregiver for any household member with a chronic illness or disability. Linear regression models were used to test for associations between chronicity of care and TL. Interaction terms were used to test whether or not the association between chronicity of care and TL differed by sex, age, and relationship to the caregiver. Specific statistical designs were publicly pre-registered before analysis began. Results Chronicity of care was not associated with TL. Neither did we find any evidence for caregiving varying in its effect on TL by caregiver sex, age, or relationship to the chronically ill/disabled. Conclusions We found no evidence of an association between chronicity of care and TL. This result coupled with a recent study of a similarly sized cohort suggests that previous significant results linking caregiving and TL may be due to very particular types of caregiving populations or are possibly artifacts of small sample sizes. [ABSTRACT FROM AUTHOR]

A deep belief network (DBN) is effective to create a powerful generative model by using training data. However, it is difficult to fast determine its optimal structure given specific applications. In this paper, a growing DBN with transfer learning (TL-GDBN) is proposed to automatically decide its structure size, which can accelerate its learning process and improve model accuracy. First, a basic DBN structure with single hidden layer is initialized and then pretrained, and the learned weight parameters are frozen. Second, TL-GDBN uses TL to transfer the knowledge from the learned weight parameters to newly added neurons and hidden layers, which can achieve a growing structure until the stopping criterion for pretraining is satisfied. Third, the weight parameters derived from pretraining of TL-GDBN are further fine-tuned by using layer-by-layer partial least square regression from top to bottom, which can avoid many problems of traditional backpropagation algorithm-based fine-tuning. Moreover, the convergence analysis of the TL-GDBN is presented. Finally, TL-GDBN is tested on two benchmark data sets and a practical wastewater treatment system. The simulation results show that it has better modeling performance, faster learning speed, and more robust structure than existing models. Note to Practitioners—Transfer learning (TL) aims to improve training effectiveness by transferring knowledge from a source domain to target domain. This paper presents a growing deep belief network (DBN) with TL to improve the training effectiveness and determine the optimal model size. Facing a complex process and real-world workflow, DBN tends to require long time for its successful training. The proposed growing DBN with TL (TL-GDBN) accelerates the learning process by instantaneously transferring the knowledge from a source domain to each new deeper or wider substructure. The experimental results show that the proposed TL-GDBN model has a great potential to deal with complex system, especially the systems with high nonlinearity. As a result, it can be readily applicable to some industrial nonlinear systems. [ABSTRACT FROM AUTHOR]

Abstract SrAl 2 O 4 monoclinic and Sr 12 Al 14 O 33 cubic phase nanocrystals were synthesized using sol-gel route and their morphology verified with X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM) to confirm the crystallinity of the samples and the crystallites nanoscale. Luminescence emissions were investigated by Optically Stimulated Luminescence (OSL) and Thermoluminescence (TL) methods in samples thermally treated at 1000 °C for 2 h and irradiated with β particles. TL glow curve was complex with 9 individual peaks, which was analyzed by T m -T stop method, general order kinetic theory using Computerized Glow Curve Deconvolution (CGCD). A thermal transfer TL phenomenon was observed when the samples were pre-heated in T m -T stop procedure. CW-OSL decays measured at 30 °C have high intensities even in low doses region and curves were deconvoluted using general order kinetic theory suppling two components for low doses and three components for high dose. Highlights • SrAl 2 O 4 monoclinic and Sr 12 Al 14 O 33 cubic phase nanocrystals were synthesized using sol-gel route. • Crystallites sizes by Scherrer Equation were about (42 ± 7) nm for cubic phase and (35 ± 4) nm for monoclinic phase. • Computerized Glow Curve Deconvolution (CGCD) and T m -T stop were used for TL emission. • CW-OSL curves were deconvoluted using general order kinetic. • CW-OSL intensities even in low doses region, supplying a minimum detectable dose of 2 mGy. [ABSTRACT FROM AUTHOR]

• CaSiO 3 doped with Eu, at various amounts in ppm, has been produced by the devitrification method. • 1000 ppm of Eu doped CaSiO 3 display dosimetric capability to very high gamma radiation dose (kGy). • The largest contribution of the TL response comes from photons with wavelengths between 400 and 440 nm. • PL measurements show the presence of both Eu2+ and Eu3+ ions in the CaSiO 3 :Eu matrix. • O− ion and two different F+ centers have been identified in the gamma-irradiated CaSiO 3 : Eu phosphor. CaSiO 3 doped at different ppm of Eu were synthesized by the devitrification method. Polycrystals exhibit a prominent high-temperature TL peak that increases in intensity and shifts toward higher temperatures with increasing amounts of dopant. TL emission spectrum of CaSiO 3 : Eu displays two very broad bands centered at 400 and 440 nm corresponding to the temperatures of 229.5 and 373.5 °C, respectively. PL measurements indicate the presence of Eu2+ and Eu3+ ions. EPR spectrum arises from two defect centers. One of the centers with principal g -values 2.016, 2.0091, and 2.0051 is attributed to O− ion and the center correlates with the TL peak at 236 °C. Center II with an isotropic g -value of 2.0018 is attributed to an F+ center and the center relates to the TL peak at 120 °C. Center III is also tentatively identified as the F+ center which is associated with the TL peak at 365 °C. [Display omitted] [ABSTRACT FROM AUTHOR]

Opercula of the gastropod Bithynia tentaculata are composed of calcite, and are typically 2–4 mm in length. They emit a thermoluminescence (TL) signal that can be used for dose reconstruction, and spatially resolved TL data from them can be obtained using an electron multiplying charge coupled device (EMCCD). However, when multiple measurements are made of the same sample with imaging detectors such as the EMCCD, registering the different images is crucial so that when regions of interest (ROI) are defined they consistently relate to the same part of the specimen. Previous work on opercula has undertaken this registration by hand, but this is prohibitively time consuming and is also potentially prone to human error. An automated registration process is described, and its use is illustrated using a dose recovery experiment. Without registration more than half of the regions of interest defined across the operculum failed the recycling test, and for those ROIs which did pass recycling the dose recovery ratio varied from 0.7 to 1.2. After registration more than 97% of ROIs passed recycling and all these ROIs gave dose recovery ratios within two sigma of unity. The automated registration process described here has potential for application to other types of solid sample such as rock slices provided they are not perfectly circular. • Imaging detectors providing new insights for dosimetry. • Registration of images essential for accurate spatially resolved analysis. • Automated image registration described for calcitic opercula. [ABSTRACT FROM AUTHOR]

Accurate photovoltaic (PV) power forecasting is pivotal for optimizing the integration of RES into the grid and guaranteeing proficient energy management. Concurrently, the sensitive nature of data obtained from individual PV systems underscores paramount concerns regarding data privacy and security. In this manuscript, we introduce an innovative approach for PV power forecasting that addresses these concerns, deploying federated learning (FL) combined with TL. This is orchestrated via a hybrid deep learning model, denominated as Federated transfer learning (TL) Convolutional Neural Network with Stacked Gated Recurrent Unit (FL-TL-Conv-SGRU). To optimize the performance of the Conv-SGRU model, we employ the OA for hyperparameter tuning, a novel bio-inspired technique inspired by orchard gardening practices. This algorithm presents a distinctive interplay between exploration and exploitation in the hyperparameter space, potentially elevating the model's performance. Our exposition covers eight disparate datasets from PV systems, which are judiciously split into two cohorts, safeguarding data privacy. Through the prism of FL, we ensure data security by orchestratively training the Conv-SGRU model over distributed datasets. This strategy allows tapping into the shared wisdom across the datasets, all the while ascertaining individual data remains localized, boosting model generalization and predictive prowess. Additionally, TL is invoked to benefit from pre-trained feature representations, facilitating effective knowledge transmission across diverse PV setups with unique characteristics and locales. The put-forth FL-TL-Conv-SGRU design amalgamates the essence of FL, TL, convolutional neural networks, and stacked gated recurrent units. This ensemble aids in deciphering spatial–temporal intricacies intrinsic to PV power generation. Through empirical analyses, we evince that our FL-TL-Conv-SGRU model transcends conventional forecasting paradigms, emphasizing its adeptness in delivering meticulous forecasts over a range of PV installations. Our results accentuate the bifurcated importance of the federated TL framework: a capability for collaborative training with an unwavering commitment to data privacy, and a proficiency in exploiting decentralized data. This strategy is particularly salient given the shifting regulatory milieu centered on data safeguarding and confidentiality. As we transition towards a world more reliant on renewable energy, our proposed stratagem promises to be a cornerstone for efficient, sustainable energy management, heralding a future replete with green energy. [ABSTRACT FROM AUTHOR]

This work studied the synthesis route and gadolinium (Gd) doping concentration on magnesium tetraborate (MBO) luminescence response. The material was synthesized by solid-state reaction techniques with two different procedures (Routes A and B) for three different Gd concentrations (0.2, 0.3, and 0.7 %wt). Route A consisted of the synthesis of the MBO matrix and subsequently add Gd 2 O 3 as an activator. Route B the material was obtained after mixing and co-milling the precursors and the activator together prior to synthesis. Rietveld refinement of experimental X-ray diffraction data indicates that the MgB 4 O 7 :Gd compounds exhibit single phases consistent with orthorhombic symmetry (space group Pbca (61)). These compounds also evidenced contributions Gd dopant concentrations in MgB 4 O 7 matching the cubic symmetry of the material. The electron microscopic scan surface morphological study exhibited the formation of polycrystalline material with diverse grain shapes for the two production routes. Compositional characterization by electron X-ray energy spectroscopy suggested that there were no other elements besides the expected elements in the material. The optical response by diffuse reflectance spectroscopy estimated the energy gap from the fundamental absorption of the undoped host. Optically stimulated luminescence response suggested that MgB 4 O 7 :Gd 0.7%wt (route B) sensitivity is 2.1 times higher than that presented in MgB 4 O 7 :Gd 0.3 % (route A). Thermoluminescence experiments showed that the optimum Gd dopant concentrations for the most intense dosimetric peak of phosphorus MgB 4 O 7 fabricated using routes A and B were 0.3 % (main peak: 209 °C) and 0.7 % (main peak: 276 °C), respectively. The thermoluminescence sensitivity of MgB 4 O 7 :Gd 0.3%wt (route A) is 3.5 times higher than the sensitivity of MgB 4 O 7 :Gd 0.7%wt (route B). • Phosphorus MgB 4 O 7 :Gd was synthesized by two synthesis routes of the solid state reaction method. • Structural characterizations of phosphor were studied using XRD and SEM techniques. • Optimized dopant concentration for maximum TL sensitivity. • OSL signals from MgB 4 O 7 :Gd were evaluated, showed stability along the time. • Kinetic parameters such as E , b and s were obtained. [ABSTRACT FROM AUTHOR]

This paper is focused on the channel modeling techniques for implementation of narrowband power line communication (NB-PLC) over medium voltage (MV) network for the purpose of advanced metering infrastructure (AMI). Three different types of models, based on deterministic method, statistical method, and network parameters based method are investigated in detail. Transmission line (TL) theory model is used to express the MV network as a two-port network to examine characteristics of sending and receiving NB-PLC signals. Multipath signal propagation model is used to incorporate the effect of multipath signals to determine the NB-PLC transfer function. A Simulink model is proposed which considers the values of MV network to examine the characteristics of NB-PLC signals. Frequency selectivity is also introduced in the impedances to compare variations and characteristics with constant impedances based MV network. A state-of-the-art mechanism for the modeling of capacitive coupling device, and impedances of low voltage (LV) and MV networks is developed. Moreover, a comparative analysis of TL theory and multipath signal propagation models with the proposed Simulink model is presented to validate the performance and accuracy of proposed model. This research work will pave the way to improve the efficiency of next-generation NB-PLC technologies.

The significance of input, namely meaning-bearing linguistic instances of the target language (TL) (VanPatten, 1996), in accounting for how learners create second language (L2) grammars has long been established (Gass, 1997). Krashen (1985), in his Input Hypothesis, even argues that the sheer provision of abundant comprehensible input would be “necessary and sufficient” for second language acquisition (SLA). In light of such characteristics as “lack of success” and “the importance of instruction” in Bley-Vroman’s (1989) Fundamental Difference Hypothesis vis-à-vis adult L2 learners, however, it appears that manipulating aspects of learning conditions may facilitate L2 grammar acquisition. Some researchers (e.g., Sanz and Morgan-Short, 2005) suggest that external manipulation ofinput through textual (Jourdenais, Ota, Stauffer, Boyson, & Doughty, 1995) or prosodic (Leeman, 2003) enhancement, or even input flood (Trahey & White, 1993) might induce internal processing, considering that the target forms are made more salient and are thus more likely to be detected by the learner. Others (e.g., Chaudron, 1983; Corder, 1967; Faerch & Kasper, 1980; Krashen, 1982; Sharwood Smith, 1986; VanPatten, 1996, 2002a, 2004a, 2007), while acknowledging the difficulty of controlling and measuring L2 processing, still see value in theorizing about the learner’s internal language acquisition mechanism to make sense of the manner input processing (IP) works, i.e., what kind of L2 input gets converted to intake and the rationale behind it.

Highlights • Multiple anode configurations allows for the spatial separation of luminescence and UV-fluorescence. • Modulation of the high-voltage during measurements is able to separate the UV-fluorescence from luminescence. • UV-fluorescence may provide a more sensitive measurement of exo-electrons from quartz and feldspars. Abstract The measurement of OSL/TL relies on the initial trapping and subsequent release and recombination of charge in a suitable crystal structure. These measurements allow us to estimate the dose which the crystal has been subjected to and its age. During such processes, however, electrons can be emitted from the sample surface; the ability to measure such exo-electrons can provide information regarding the trapping process, as well as an alternative method of measuring trapped charge. Ideally, TL/OSL can be measured alongside exo-electrons. We will present a new design for an exo-electron detector compatible with the classic Risø reader stimulation head featuring multiple anode configurations and the option for high-voltage modulation to reduce the UV component during TL/OSL measurements. [ABSTRACT FROM AUTHOR]

Abstract The present work describes the role of antisite defects centers in determining the phosphor characteristics of MgAl 2 O 4 , arising due to inversion nature of the spinel compound. The diverse decay characteristics impart this material both as long persistent bluish phosphor as well as short persistent red phosphors material depending upon the annealing temperature. TL study confirmed the fact that there are several defect centers which acts as electron and hole trap centers inside the band gap. FTIR and DRS study confirmed the presence of antisite defects centers viz. Al Mg + or Mg Al −, which act as an electron and hole trap centers and thereby delaying the electron-hole recombination process. Lower inversion nature of this spinel compound at higher annealing temperature results in decay in those defects concentration, as reflected in lifetime values. Graphical abstract MgAl 2 O 4 can be used both as long persistent blue emitting and as well as short persistent red emitting phosphor material depending on the annealing temperature during synthesis. Antisite defect centers such as [Al3+ Zn ] + and [Zn2+ Al ]- act as electron and hole trap centers as confirmed by TL, FTIR and DRS study are responsible for the lifetime behavior. Image 1 Highlights • The paper describes defect induced emission in MgAl 2 O 4 phosphor and role of antisite defects centers in determining the phosphor characteristics. • Upon thermal annealing the lifetime values for some color components reduced from several milliseconds to microseconds, which renders the material both as long persistent or short persistent phosphor. • TL study showed that there are several defect related trap centers present inside the band gap. • The inversion nature of the spinel compound leads to various antisite defects centers such as Al Mg + or Mg Al −, which act as a electron and hole trap centers and are mainly responsible for the diverse behaviors. [ABSTRACT FROM AUTHOR]

Abstract In this study, TL and OSL dating were applied respectively to bricks and mortars taken from a few key structures of the UNESCO World Heritage Site of Modena (northern Italy). The samples came from the Cathedral and the Ghirlandina Tower, built between the end of the XII century and the first half of the XIV century AD. TL dating of bricks showed that we were dealing with the well-known phenomenon of re-use of ancient Roman bricks. However, it was also possible to discover and date quite precisely a previously unknown renovation phase in the Cathedral apse area (XVI century). Regarding the OSL mortar dating, both Multi-Grain and Single Grain techniques were applied on quartz grains, possibly well bleached during mortar preparation. OSL gave good results for one sample from the Cathedral and three from the Ghirlandina Tower. The other gave ages much older than expected, indicating the possible uncompleted bleaching of the quartz grains as the main problem of this dating application. Finally, the application of the Bayesian statistical approach, reducing the error associated with the data, supported a new building chronology, in particular for the Ghirlandina Tower. Highlights • TL bricks and OSL mortars dating. • Evidence of reuse of Roman bricks. • Uncompleted bleaching of the OSL signal of mortar. [ABSTRACT FROM AUTHOR]

Abstract The archaeological site of Taibeh located south of Wadi Musa, Jordan, incorporates at least two, maybe even five, successive layers associated with the Late Ahmarian, also known as Masraqan, technocomplex. The Masraqan is elsewhere connected with the beginning of the intensive use of plant food and with permanent settlements. Taibeh could be the first site to present as much as 5 successive layers of this cultural unit. The Masraqan is relatively well constrained in time, usually dated between 18 and 25 ka BP. A series of heated flints was collected at Taibeh to be dated using TL. Two informations are required for the estimation of a TL age: the equivalent dose (D e) which is the dose accumulated in the flint since it had been heated, and the dose rate (D ˙) to which the flint is exposed during the burial time. The D e estimation was done applying two different protocols, and both produced consistent results. The D ˙ estimation was realised using a modified version of DRAC (Durcan et al., 2015) which allows to use different radio-element concentrations for the flints and the surrounding sediment. [ABSTRACT FROM AUTHOR]

The paper discusses data concerning the secondary manufacture technology of a set of opaque coloured early Islamic mosaic glass tesserae from the qasr of Khirbet al-Mafjar (Jericho, Palestine). Archaeological contextualisation of the site had allowed attributing these finds to the Umayyad occupational phase of the building, and an in-depth study of the composition of the glassy matrix had provided evidence of a double supply of glass from Egypt and the Syro-Palestinian coast occurring in the production of the base glass intended to be used for the manufacture of mosaic tesserae. Here, a multi-methodological approach has been carried out to characterise colourants and opacifiers: visible reflectance spectroscopy (VIS-RS), optical microscopy (OM), scanning electron microscopy coupled with energy dispersion analysis (SEM-EDS), micro-Raman spectroscopy (micro-Raman) and X-ray diffraction (XRD) were performed on the opaque tesserae. Moreover, either optically stimulated luminescence (OSL) or thermoluminescence (TL) protocols for luminescence dating were applied on selected samples, with the aim of relating luminescence properties with the geochemical features of the glass tesserae, in the perspective of deepening the studies towards the absolute dating, an unquestionable help to the stimulating challenge of investigating ancient glass manufacture. Tin-based, phosphorus-based and copper-based opacifiers were identified, and the achieved results suggest the use of the same opacifiers and colouring agents regardless of the different base glass. Furthermore, data obtained by TL and OSL protocols revealed useful and stimulating potentialities these techniques could have in dating opaque glasses. [ABSTRACT FROM AUTHOR]

Abstract Electron paramagnetic resonance (EPR) studies have been carried out to identify the defect centers responsible for the thermoluminescence (TL) peaks in the mineral tourmaline. The mineral exhibits three TL peaks approximately at 170, 250 and 310 °C. The EPR spectrum of the green tourmaline sample pre-heated to 500 °C presented a large signal around g = 4.3 due to Fe3+ ion. Room temperature EPR spectrum of irradiated green tourmaline shows the formation of two defect centers in the region of g = 2.0. One of the centers (center II) with a g factor equal to 1.96 is identified as an F+-center and is related to the observed high temperature 250 and 310 °C TL peaks. Center I exhibiting a doublet is due to hydrogen atoms (H0), stable in the crystal lattice at room temperature and this center correlates with the TL peak at 170 °C of the green tourmaline. An optical absorption measurement also was carried out. Bands at around 430, 730 and 1100 nm have been observed. [ABSTRACT FROM AUTHOR]

Abstract Durango apatite is a material that exhibits very strong athermal fading (AF) of luminescence signal. In this study, the EPR signals of natural Durango apatite in various different grain dimensions (ball milled for various durations up to 48 h and microscale grain size) were studied. The obtained EPR signal at room temperature yielded three different components with g values 2.0534 (hole center), 2.0398 (hole center) and 1.9920 (electron center). These components were observed for the reference grain size fraction of 100–180 μm; however, prolonged ball milling erases the two hole centers. The behaviour of all obtained components was investigated by step annealing processes (a) between room temperature and 400 °C in steps of 25 °C for 5 min and (b) between 400 °C and 1100 °C, in steps of 100 °C for 1 h. The EPR component with g value 1.9918 was almost totally removed until 1100 °C, while those with g values 2.0534, 2.0398 were erased after annealing at 500 °C and 400 °C respectively. The fading of EPR components was investigated for each ball milling (BM) and microscale grain size independently, at different storage times between 0 and 1000 min. Based on the results of fading and step annealing studies, the EPR component with g value 2.0398 could be directly correlated to the main dosimetric TL trap, while the component with g value 1.9920 appears to be responsible for TA – OSL signal for microscale grain size apatite, corresponding thus to a very deep trap. The behaviour of remnant EPR signal versus storage time could be successfully described by equations based on quantum mechanical tunnelling mechanism. Highlights • EPR signal of Durango apatite (grain size fraction of 100–180 μm) yields three different components at RT. • After ball milling, only one EPR component is monitored; the other two disappear. • EPR component with g = 1.9920 could be correlated to VDTs, as the origins of TA – OSL signal, based on thermal cleaning and athermal fading results. • EPR component with g = 2.0398 could be correlated to the main dosimetric TL trap. [ABSTRACT FROM AUTHOR]

Abstract A historical radium (226Ra) needle was found in a building in Prague. The needle was concealed in a wall under a window frame. Ambient dose equivalent rate measured in close proximity to the frame reached up to 2 mSv/h. The place was located between a corridor and a staircase where people normally did not stay; hence, any significant radiation exposure was not suspected. Because of a remarkable history of the building, our speculation was that the needle could have been concealed there during World War II. To verify this assumption, one adjacent brick nearest to the place of the find was removed. The brick was used for retrospective dosimetry based on optically stimulated luminescence (OSL) of quartz extracted from a chosen brick block. Dose rate values inside the brick block were determined by a laboratory reconstruction. The original exposure conditions were simulated using the needle and a brick wall containing thermoluminescence detectors (TLDs). We also performed a computational simulation with the Monte Carlo technique. The simulation provided us a more detailed dose rate distribution inside the brick block. Finally, we compared OSL quartz, TLD, and Monte Carlo results. A good agreement among the results supports the speculation that the radium needle was concealed during World War II. Highlights • A historical radium (226Ra) needle was found in a wall. • A brick was used for dose reconstruction based on optically stimulated luminescence (OSL) of quartz. • Dose rate values inside the brick block were determined by a laboratory reconstruction with thermoluminescence detectors (TLDs). • Dose distribution was calculated using the Monte Carlo technique. • OSL, TLD, and Monte Carlo results were in a good agreement. [ABSTRACT FROM AUTHOR]

This study was aimed to analyze the thallium pollution and assess the potential ecological risks in the vicinity of coal mines in Henan province, China. We studied 90 surface farmland soil samples from 9 representative coal mines. The Tl concentrations were determined and the potential ecological risks were evaluated. Investigations revealed the farmland soils were modestly contaminated and the trace elements in coal mining areas transferred to the surface soils. Soil Tl contents and potential ecological risks in coal mining areas were significantly increased compared with the original soils which came from the villagers' mud houses built 40 years ago. The soil Tl concentrations ranged from 0.25 to 0.77(mean = 0.46) mg∙kg−1, which were higher than the original level (0.42 mg∙kg−1). The potential ecological risk index of Tl ranged from 24.00 to 73.2 (mean 44.08), representing a moderate pollution level as a whole of the soils in Henan. In general, high Tl concentrations and high potential ecological risk were found around SHQ and DTG. The soil Tl concentrations exceed the original level and pose noticeable ecological risks. [ABSTRACT FROM AUTHOR]

The Riverine Plain in south‐eastern Australia contains numerous palaeochannels that are much larger than the present rivers and provide evidence about past hydrological conditions. Previous research suggested optima in fluvial activity both before and after the peak of the Last Glacial Maximum (LGM; 21 ± 3 ka), and, in some cases, throughout the LGM. In this study, we revisit palaeochannel remnants of the Gum Creek and Yanco palaeochannel systems along the Murrumbidgee River, which drains the high‐elevation catchments of the Australian Alps in south‐eastern Australia. We date fluvial and aeolian sediments using single‐grain optically stimulated luminescence (OSL) and apply thermoluminescence (TL) dating to a subset of samples. We compare the OSL ages to new and previously published TL ages and investigate reasons for age discrepancies between these methods, possible effects of partial bleaching and other factors that may affect luminescence ages. We propose a new OSL‐based chronology for the Gum Creek and Yanco palaeochannel systems and assign periods of enhanced fluvial activity for the Tombullen and Yanco phases to 41–29 and 29–18 ka, respectively. Importantly, we infer that conditions of increased sediment and water discharge persisted for the Murrumbidgee River at the time of the LGM. [ABSTRACT FROM AUTHOR]

Abstract: In this article, the new of the transmission‐line (TL) using π‐type parameter is suggested and it applied to the design of a hybrid branch‐line coupler (HBC). The new HBC is small size than conventional HBC and the designed HBC is used by entire distributed elements. Then, the sizes of the new and conventional HBCs are 9.86 × 11.1 mm2 and 28.2 × 28.6 mm2, respectively. The advantage of the proposed HBC structure has very simple structure and low cost. The proposed HBC using π‐type TL can be applied to mobile communication system. [ABSTRACT FROM AUTHOR]

Abstract: In this article, the new compact size of the transmission line (TL) using a π‐model transformation method is suggested and applied to the design of a Wilkinson power divider (WPD). The proposed WPD is smaller than the conventional WPD, and the designed WPD is used for distributed elements. The new and conventional WPDs are 9.86 × 11.1 mm2 and 28.2 × 28.6 mm2, respectively. The advantages of the proposed WPD are its very simple structure and low cost. The proposed WPD with a compact TL using a π‐model transformation method can be applied to mobile communication systems. [ABSTRACT FROM AUTHOR]