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Osteoporosis has been recognized as a significant cause of disability in the elderly leading to heavy socioeconomic burden. Current measurements such as dual-energy X-ray absorptiometry (DEXA) and bone mineral density (BMD) have limitations. In contrast, trabecular bone score (TBS) is an emerging tool for bone quality assessment. The objective of our study was to investigate the relationship between TBS and trace elements (cadmium and lead). We analyzed all subjects from the 2005-2006 and 2007-2008 National Health and Nutrition Examination Survey (NHANES) dataset and included a total of 8,244 participants in our study; 49.4% of the enrolled subjects were male. We used blood cadmium (Cd) and lead (Pb) concentrations to define environmental exposure. The main variables were TBS and BMD. Other significant demographic features were included as covariates and later adjusted using linear regression models to determine the association between TBS and four quartiles based on the blood trace element concentrations with or without sex differences. The fully adjusted regression model revealed a negative relationship between TBS and blood cadmium (B-Cd) significant for both males and females (both p0.05). The β-coefficient for males was -0.009 (95% confidence intervals (CI): (-0.015 to -0.004)) and -0.019 for female (95% CI: (-0.024 to -0.013)). We also found a dose-dependent relationship between TBS and B-Cd for both sexes (both trend's p0.05). Our study concluded that TBS could measure Cd-related bone quality deterioration for both males and females.

Klotho is an anti-aging gene. Studies have revealed its association with insulin resistance. Visceral fat is related to insulin resistance, and the sagittal abdominal diameter (SAD) can serve as a biomarker for visceral fat (VF). This study investigated the association between SAD and serum Klotho concentration (SKC). We enrolled 2301 participants from the 2011–2012 National Health and Nutrition Examination Survey (NHANES) dataset, and 49.2% of the enrolled individuals were male. Qualified participants were separated into four quartiles according to the SAD value. SKC values were obtained by ELISA. Demographic characteristics, body mass index (BMI), systolic blood pressure, and biochemistry parameters with significance were analyzed using multivariate linear regression models. The mean age of the study participants was 57.22 ± 10.53 years. The fully adjusted regression model showed a negative association between SAD and SKC (p < 0.05), with a β-coefficient of −12.02. We also analyzed subgroups of participants according to age and BMI. Participants with an age ≥65 and

The micro-arc oxidation (MAO) process was used to prepare hydroxyapatite-containing flower-like structure coatings on commercially pure titanium substrates with various values of the applied voltage (330, 390, 450 V), applied current (0.4, 0.5, 0.6 A), and duration time (1, 3, 5 min). It was found that the surface morphology of the coatings was determined primarily by the applied voltage. A voltage of 330 V yielded a flower-like/plate-like structure, while voltages of 390 V and 450 V produced a flower-like structure and a porous morphology, respectively. The applied current and duration time mainly affected the coating formation speed and petal size of the flower-like structures, respectively. The coatings prepared using voltages of 330 V and 390 V (0.6 A, 5 min) both contained Ti, TiO2-A (anatase), TiO2-R (rutile), DCPD (CaHPO4·2H2O, calcium hydrogen phosphate), and hydroxyapatite (HA). However, the latter coating contained less DCPD and had a higher HA/DCPD ratio and a Ca/P ratio closer to the ideal value of HA. The coating prepared with a voltage of 450 V consisted mainly of Ti, TiO2-A, TiO2-R, and CaTiO3. For the coatings prepared with a voltage of 390 V, the flower-like structures consisted mainly of HA-containing compounds. DCPD plate-like structures were observed either between the HA-containing flower-like structures (330 V samples) or within the flower-like structures themselves (390 V samples). The coating surfaces with flower-like/plate-like or flower-like structures had a greater roughness, which increased their hydrophilicity and resulted in superior bioactivity (SBF immersion) and biocompatibility (MG-63 cell culture). The optimal biomedical performance was found in the 390 V coating due to its flower-like structure and high HA/DCPD ratio.

Objectives: To try another non-invasive method to evaluate the relationship between Magnetic Resonance (MR) elastic value and pathological grade of Hepatocellular Carcinoma (HCC) using Magnetic Resonance Elastography (MRE). Methods: Forty-seven HCC patients underwent MR Imaging (MRI), elastography in the upper abdomen. The elastic value of the lesion area was measured, and that of the normal liver tissue was measured adjacent to the lesion area at the same level. The Mann-Whitney U test was used to compare the difference in elasticity between the lesion area and normal area, and the difference between the low and middle-high differentiation groups. The Receiver Operating Characteristic Curve (ROC) of the lesion area and normal area in the complete case group and different differentiation groups were used to determine the diagnostic cut-off value to distinguish the lesion area from the normal area in each group. Results: (1) There was a significant difference in elasticity between the normal area and HCC area (p

Traditionally, doctors have used stethoscopes for chest auscultation to diagnose respiratory and heart diseases. Auscultation can be used to initially diagnose the status of the patient, but this depends on the doctor's experience and waste time. Recently, electronic auscultation is proposed to diagnose the condition more carefully by sampling and processing sound signals. This paper designs a simple self-made stethoscope to digitize medical sound data. The sounds are then analyzed to give preliminary diagnosis to track health condition. The wave of monitored sounds and analyzed results can be displayed on mobile phones, so that patients can know health status immediately. In addition, an e-health home gateway and cloud-based AI system are also proposed for home-care patients to monitor health condition of chronic patients anytime at home or long-care center.

Steganography poses a serious challenge to forensics because investigators cannot identify even traces of secret messages embedded using a steganographer. Contrarily, the objective of locating steganalysis is to locate the embedded message, which should help extract the secret message. In this paper, a methodology of locating steganalysis using quantitative steganalysis is presented for multiple stego images with embedded messages along the same embedding path. Three typical quantitative steganalysis methods are applied to the methodology to locate the messages embedded using LSB re-placement. Experimental results show that the presented methods can reliably estimate the embedding positions, which verifies the validity of the presented methodology. The presented methodology points out a new use of quantitative steganalysis, and further demonstrates that it is necessary to design more precise quantitative steganalysis methods.

In this paper, we propose a differentially fed ultrawideband (UWB) quasi-self-complementary (QSC) antenna with a 5.5-GHz notch band. By designing the first five modes of the complementary antenna in the passband, the desired UWB response is achieved. To suppress the common-mode (CM) signals, instead of directly connecting to the complementary antenna, the differential feedline is deployed symmetrically across the input slotline so that weak coupling can be established when in CM operation. A 5.5-GHz notch band for preventing undesired WLAN signals is implemented by tapping λ/4 open stubs near the bisection plane. The differentially fed UWB complementary antenna have good differential-mode (DM) performance, high CM rejection, as well as low DM-to-CM conversion. The measured results show that the 10-dB DM passband is from 2.75 to 11.01 GHz, except the notch band; the CM reflection coefficient is greater than −2.62 dB and the DM-to-CM conversion is lower than −24.7 dB in the 2–12 GHz frequency range.

The surface morphology and combustion characteristics of micron-scale rice husks with different particle sizes were studied in detail by the fractal theory and thermogravimetric test. The calculation results by the box-counting dimension and erosion method were consistent with the actual data. The fractal dimensions first increased and then decreased with the rising particle sizes of rice husks. The largest fractal dimension and best combustion performance were found in 150 μm rice husk. The experiment results were verified finally by thermogravimetric tests, which were consistent with the theoretical results based on the fractal theory. The fractal theory of box-counting dimension and erosion provides a feasible method for studying biomass combustion characteristics.

Single crystals of Sr 3 Cr 2 O 8 , Sr 3 Cr 1.9 V 0.1 O 8 and Sr 3 Cr 1.9 Fe 0.1 O 8 were grown using the floating zone technique, and their magnetization behaviors were systematically investigated under pulsed field up to 54 T at various temperatures ranging from 2 K to 20 K. Temperature-induced transition from singlet ground state to triplet state and magnetic-field-induced Bose–Einstein condensation were observed, of which the critical temperature and the critical field are correlative to ion-dopants. The analysis of the ground state and low-field magnetization behaviors indicates that the ion-dopants lead to an enhancement of the intradimer exchange J 0 , which changes the transition temperatures, and increases the critical fields H c1 . The magnetic Fe ion dopant makes the transition from singlet to triplet states more sensitive to the applied magnetic field, in clearly contrast to the situation of the nonmagnetic V 5+ dopant.

In this study we report detailed magnetic property of the 4f-3d pseudo-quaternary Tb0.2Pr0.8(Fe0.4Co0.6)1.88C0.05 compound by detailed magnetization measurements. Very sharp magnetization jumps across the antiferromagnetic–ferromagnetic transition are observed below 3.0 K, and the number of jump-like transitions increases with decreasing temperature. The time-dependent magnetic relaxation, field sweep rate and cooling field dependence of magnetization jumps resemble the martensitic scenario. The number and occurrence of magnetization jumps are mainly determined by the competitions between the thermal fluctuation energy, elastic energy and Zeeman energy, and the field-induced antiferromagnetic to ferromagnetic phase transition at low temperatures is of first-order in nature.

This paper introduces a supercell model to explain the field-induced multiple transitions and the anomalous dilution effect in the nonmagnetic-substituting intermetallic compounds Dy 50− x Al x Ag 50 , in which the shift of the field-induced transitions in the Al-doped samples results from the change of the magnetic structure. At the doping level of x =1.8 (the ratio of Al/Dy approximates 1/26), an anomalous magnetic dilution effect was observed, in which the dilution effect becomes weak and the magnetic behavior is fairly similar to that of pure DyAg. We assumed that the anomalous dilution effect mainly results from the formation of uniform distribution of supercell in the doped Dy 48.2 Al 1.8 Ag 50 .

This study used three kinds of wax and three kinds of oil, with fixed mixture ratio including UV-blocking materials of ethylhexyl methoxycinnamate, oxybenzone, and avobenzone, and applied hot high-pressure homogenization process to prepare nanolipid sunscreen formulations. The measured particle size of the sunscreen formulations was 100~300 nm around PDI of 0.2 having a moderate polydisperse system. The distribution of zeta potential was −50 mV to −35 mV, showing a stable system. The UV light-absorbing range of 9 groups of sunscreen formulations was 275 nm~380 nm ranging within UVA and UVB. The rheological analysis found that the viscosity change is shear, thinning exhibiting colloid behavior. Taguchi analysis found that the optimum combinations are the carnauba wax and the blackcurrant oil combination for crystallinity and the beeswax and CPG oil for UV absorption. In addition, UV-blocking ability shows that the SPF was 51.5 and PFA was three stars for SU9 formulation. Finally, the effect of temperature on the properties of sunscreen formulations was also explored.

The enhanced 2D layered structure single crystalline TlCo2Se2 has been successfully fabricated, which exhibits field-induced 3D spin-flop phase transitions. In the case of the magnetic field parallel to the c-axis (B//c), the applied magnetic field induces the evolution of the noncollinear helical magnetic coupling into a ferromagnetic (FM) state with all the magnetization of the Co ion parallel to the c-axis. A striking variation of the field-induced strain within the ab-plane is noticed in the magnetic field region of 20-30 T. In the case of the magnetic field perpendicular to the c-axis (B ⊥ c), the inter-layer helical antiferromagnetic (AFM) coupling may transform to an initial canted AFM coupling, and then part of it transforms to an intermediate metamagnetic phase with the alignment of two-up-one-down Co magnetic moments and finally to an ultimate FM coupling in higher magnetic fields. The robust noncollinear AFM magnetic coupling is completely destroyed above 30 T. In combination with the measurements of magnetization, magnetoresistance and field-induced strain, a complete magnetic phase diagram of the TlCo2Se2 single crystal has been depicted, demonstrating complex magnetic structures even though the crystal geometry itself gives no indication of the magnetic frustration.

Although fosfomycin is a treatment option for infections caused by extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae, fosfomycin resistance has been documented. To our knowledge, fosfomycin resistance mechanisms in Klebsiella pneumoniae have not been systematically investigated. A total of 108 ESBL-producing K. pneumoniae isolates collected from Kaohsiung Medical University Hospital, Taiwan, from August 2012 to May 2013 were analysed in this study. Pulsed-field gel electrophoresis (PFGE) revealed 64 pulsotypes and six non-typeable isolates, indicating high genetic diversity. Moreover, pulsotypes V (n = 6), VII (n = 11) and LI (n = 4) belonging to ST11 were major types. Among 30 (27.8%) fosfomycin-non-susceptible isolates, 21 (70%) had a MurA amino acid substitution, and seven new variations increased the fosfomycin minimum inhibitory concentration (MIC) by 8- to 16-fold compared with wild-type MurA in Escherichia coli DH5α.strain. Functionless transporters (GlpT and UhpT) with various mutations were found in 29 isolates (97%). No known fosfomycin-modifying enzymes were detected in this study. The major resistance mechanisms to fosfomycin in K. pneumoniae were amino acid variations in the drug target and transporters.

Measurements of the isothermal magnetization on La0.27Nd0.4Ca0.33MnO3 have been performed in a field up to 7 T at various temperatures. A distinct field-induced metamagnetic transition is observed within a temperature region of 2–180 K, resulting from the coexistence of charge ordered (CO), antiferromagnetic (AFM) and ferromagnetic (FM) phases. A temperature and magnetic field dependent irreversible CO–FM transition appears in the lower temperature region. Accompanying the transition an obvious lattice strain was observed, indicating that the transition is related to the change of lattice strain due to strong spin–lattice coupling in La0.27Nd0.4Ca0.33MnO3. These properties make the doped manganites a good candidate for a magnetostriction sensor material.

We present a conditional simulation algorithm to parameterize three-dimensional heterogeneities and construct heterogeneous petrophysical reservoir models. The models match the data at borehole locations, simulate heterogeneities at the same resolution as borehole logging data elsewhere in the model space, and simultaneously honor the correlations among multiple rock properties. The model provides a heterogeneous environment in which a variety of geophysical experiments can be simulated. This includes the estimation of petrophysical properties and the study of geophysical response to the heterogeneities. As an example, we model the elastic properties of a gas hydrate accumulation located at Mallik, Northwest Territories, Canada. The modeled properties include compressional and shear-wave velocities that primarily depend on the saturation of hydrate in the pore space of the subsurface lithologies. We introduce the conditional heterogeneous petrophysical models into a finite difference modeling program to study seismic scattering and attenuation due to multi-scale heterogeneity. Similarities between resonance scattering analysis of synthetic and field Vertical Seismic Profile data reveal heterogeneity with a horizontal-scale of approximately 50 m in the shallow part of the gas hydrate interval. A cross-borehole numerical experiment demonstrates that apparent seismic energy loss can occur in a pure elastic medium without any intrinsic attenuation of hydrate-bearing sediments. This apparent attenuation is largely attributed to attenuative leaky mode propagation of seismic waves through large-scale gas hydrate occurrence as well as scattering from patchy distribution of gas hydrate.

High-quality single-crystal Sr6Co5O15–δ (δ = 1.33) was successfully synthesized with a flux method. Detailed crystalline structure was determined by single-crystal X-ray diffraction at 298 K, which revealed a quasi-one-dimensional Co–O chain-like structure of this oxygen-deficient material. The magnetizations were measured in a pulsed high magnetic field up to 32 T and with a Physical Property Measurement System (PPMS). A large anisotropy and a distinct spin-flip transition were observed in the magnetization behavior. Theoretical calculation based on Botana's results suggests that interchain interaction (non-one-dimensional magnetic coupling) plays an important role in the magnetic properties of Sr6Co5O15–δ.

SUMMARY We present a joint transmission and reflection traveltime tomography algorithm based on the Fast Sweeping Method and the adjoint-state technique. In contrast to classical ray based tomography, this algorithm utilizes a grid-based Eikonal equation solver to circumvent the non-linearity of conventional ray shooting and bending approaches in complex media. The adjoint-state technique is used to obtain the gradient of the objective function without the explicit estimation of the Frechet derivative matrix, which is usually computationally prohibitive for large-scale problems. When combined with Huygens’ Principle, the tomographic inversion can simultaneously use direct and reflected arrivals to optimize a final velocity model, further mitigate the ambiguity of the inverse problem and reveal deeper structures not visible to transmission tomography alone. In this paper, we describe the theoretical basis of our algorithm, evaluate its performance on synthetic models, and then apply it to a 20 km long 2-D seismic survey acquired in the Mackenzie Delta, Northwest Territories of Canada. The subsurface at that location is characterized by a thick permafrost (600 m) comprising high- and low-velocity areas associated with thermokarst lakes. Our results show the potential of the joint tomography in characterizing multi-scale heterogeneous velocity structures within the permafrost.

We propose an application of joint tomographic inversion using both transmitted and reflected arrivals to map velocity structures in thick permafrost areas of the Mackenzie Delta, Northwest Territories of Canada. Our tomography algorithm combines a grid-based solver of the eikonal equation, Huygens' principle, and the adjoint method. The grid-based solver assigns a traveltime to each grid point and avoids the shadow-zone problem in classical ray tracing and is well-adapted for parallelization. The adjoint method used in the inversion provides the gradient of a given objective function without explicitly estimating the Fréchet derivative matrix. When combined with Huygens' principle, the tomographic inversion can simultaneously use first and later arrivals to optimize a final velocity model. We first demonstrate the performance of the joint tomography algorithm on a two-dimensional synthetic model with velocity variations typical of permafrost. The method is then applied to a 2D seismic survey covering over 20 km with offsets up to 4 km, acquired in the Mackenzie Delta. The subsurface at that location is characterized by a thick permafrost (600 m) comprising high-velocity and low-velocity areas associated with thermokarst lakes. Our results show the potential of the joint tomography in characterizing multiscale heterogeneous velocity structures within the permafrost.

Two yttrium(III) coordination compounds, [Y(a3-ptz)2(H2O)5]Cl · 4H2O (1) and [Y(atza)2(H2O)2(CH3OH)]Cl (2) [a3-ptz = 5-[N-acetato(3-pyridyl)]tetrazole; atza = 5-aminotetrazole-1-acetato], have been synthesized. Single-crystal X-ray diffraction analysis reveals that 1 has a distorted monocapped square-antiprism coordination geometry around YIII. Complex 2 is a distorted pentagonal bipyramid with coordination from four atza ligands, two waters, and one methanol; the coordination of atza in 2 leads to its 1-D polymeric chain structure. 1 and 2 are self-assembled to form 3-D supramolecular structures through hydrogen bonds. The luminescence properties of 1 and Ka3-ptz were investigated at room temperature in the solid state.

Through applied voltage (VAC), the characteristic of dye-doped liquid crystal random lasers (DDLC-RLs) inside capillary fiber (CF) has been readily and efficiently modulated. As VAC rose, the intensity of the emission spike increased dramatically at a fixed excited energy, and the slope efficiency of DDLC-RL increased obviously. By means of the white light scattering spectrum, the increase in the output from DDLC-RL is attributed to the enhancement of recurrent light scattering within the liquid crystals (LCs) to strengthen the light localization. In order to distinguish the characteristic of DDLC-RL with VAC = 0 V and 60 V, the α-stable distribution was adopted to show the Levy distribution of intensity fluctuation with a reduction in value from α = 1.86 to α = 1.59.

An innovative fabrication method to produce a macroporous Si surface by employing an anodic aluminium oxide (AAO) nanopore array layer as an etching template is presented. Combining AAO with a reactive ion etching (RIE) processes, a homogeneous and macroporous silicon surface can be effectively configured by modulating AAO process parameters and alumina film thickness, thus hopefully replacing conventional photolithography and electrochemical etch methods. The hybrid process integration is considered fully CMOS compatible thanks to the low-temperature AAO and CMOS processes. The gas-sensing characteristics of 50 nm TiO(2) nanofilms deposited on the macroporous surface are compared with those of conventional plain (or non-porous) nanofilms to verify reduced response noise and improved sensitivity as a result of their macroporosity. Our experimental results reveal that macroporous geometry of the TiO(2) chemoresistive gas sensor demonstrates 2-fold higher (∼33%) improved sensitivity than a non-porous sensor at different levels of oxygen exposure. In addition, the macroporous device exhibits excellent discrimination capability and significantly lessened response noise at 500 °C. Experimental results indicate that the hybrid process of such miniature and macroporous devices are compatible as well as applicable to integrated next generation bio-chemical sensors.

A class of nanoporous TiO2 gas sensors processed by novel anodic aluminum oxidation (AAO) of Al thin films and microelectromechnical systems (MEMS) techniques are presented. To enhance the sensitivity and reduce the sensing dimensions of a gas sensor, a nanoporous surface of the gas-sensitive material on the sensor is required. These sensors can be implemented on silicon or silicon dioxide substrate featuring a thin membrane of micro-hotplate structure featuring micro-heaters, thermometers and electrodes, and thus operate as chemoresistive devices. Combining the AAO method with dry-etch process, a homogeneous and nanoporous SiO2 surface of the sensor can be effectively configured by modulating various hole diameters and depth, hence replacing conventional photolithography and electrochemical etch. The process integration including AAO, reactive ion etch (RIE) and microfabrication is mainly developed and a feasibility study of PVD TiO2 thin film deposition upon the porous device is also provided. TiO2 thin films deposited on the nanoporous surface are investigated and compared with non-porous TiO2 films. It is encouraging that our fabrication process is able to provide relatively high surface area to enhance sensitivity of the sensor without additional doping steps. Our promising experimental results have revealed these miniature and cost-effective devices are not only compatible, but applicable to smart bio-chemical sensors of next generation.

This research studies the heat transfer characteristic of an unsteady close-contact melting on a flat plate in the cool-thermal discharge systems with external recycle, develops the mathematical model theoretically to simulate the conduction-convection heat-transfer phenomena, and calculates the theoretical prediction of the outlet chilled air temperature by solving the energy balance associated with integral boundary-layer analysis. It is found that the recycle effect can enhance the average Nusselt numbers and heat-transfer efficiency improvement effectively. Three numerical examples of inlet ambient air temperature are illustrated to compute the chilled air temperature, average Nusselt numbers and heat-transfer efficiency with three specified volumetric flow rate and three traversed length of the ambient inlet air as parameters.

The fast sweeping method has been proved very efficient in calculating the first arrivals in isotropic media. In this study, we extend the fast sweeping method to heterogeneous anisotropic medium by adapting the Lax-Friedrichs local scheme. The new fast sweeping method is able to solve the first arrival traveltime field for both qP and qS waves. By comparing the traveltime field to the full-waveform solution, we demonstrate that the iso-surfaces of the time field follow the constant phase of the wave and form a continuous envelope wrapping the wavefront. The iso-surfaces for the shear wave identify two continuous wavefronts one ahead of the other even in the directions where the triplication of qS-wave is developed. The rays for both qP and qS wave can be traced using the slowness vector from the traveltime field and we compared its accuracy with a two-point ray tracing method in a layered model. We show that rays from the traveltime field is nearly identical to the two-point ray tracing results. This new fast sweeping method not only avoids the multipath and shadow zone issues in complex heterogeneous media but also circumvent the multiple shear branch problems due to anisotropy.

Magnetization behavior of (La 0.83 Bi 0.17 ) 0.67 Ca 0.33 MnO 3 has been investigated in the temperature range from 100 to 180 K. A metamagnetic transition was observed in the temperature region, where the magnetization was measured after a zero-field-cooling from room temperature to a selected temperature. Experimental results show that, after a higher magnetization route, the field-increasing branches of the magnetization curves shows an unusual training effect: below a magnetic field H 0 , the applied magnetic field enhances the value of magnetization; however, above H 0 the magnetic field suppresses the value, and the behavior cannot be totally attributed to the enhancement effect of the applied magnetic field on ferromagnetic phase fraction. It is proposed that, in the two-phase coexistence region, the higher magnetic field promotes the phase separation and leads to both the fraction of ferromagnetic domain and the stabilization of antiferromagnetic domain increase.

Passive monitoring of induced microseismic (MS) events provides a unique means for imaging fracture propagation in response to engineering operations. Particularly during hydraulic treatment of hydrocarbon-bearing reservoirs rock MS monitoring provides feedback to field operators on the effect of the treatment and the changes imposed on the fracture network and fluid conductivity within the rock.

Based on Lax-Friedrichs scheme, we developed a new fast sweeping method of calculating the direct traveltime field for both quasi-Pand quasi-S-wave in general anisotropic media. The ray vector and the polarization can be obtained from the slowness vector at any given points in the model and the seismic ray path can be traced following the opposite direction of ray vectors. We illustrate the efficiency and accuracy of this new algorithm using 2-D and 3-D numerical examples.