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Tight-binding approaches, especially the Density Functional Tight-Binding (DFTB) and the extended tight-binding schemes, allow for efficient quantum mechanical simulations of large systems and long-time scales. They are derived from ab initio density functional theory using pragmatic approximations and some empirical terms, ensuring a fine balance between speed and accuracy. Their accuracy can be improved by tuning the empirical parameters using machine learning techniques, especially when information about the local environment of the atoms is incorporated. As the significant quantum mechanical contributions are still provided by the tight-binding models, and only short-ranged corrections are fitted, the learning procedure is typically shorter and more transferable as it were with predicting the quantum mechanical properties directly with machine learning without an underlying physically motivated model. As a further advantage, derived quantum mechanical quantities can be calculated based on the tight-binding model without the need for additional learning. We have developed the open-source framework—Tight-Binding Machine Learning Toolkit—which allows the easy implementation of such combined approaches. The toolkit currently contains layers for the DFTB method and an interface to the GFN1-xTB Hamiltonian, but due to its modular structure and its well-defined interfaces, additional atom-based schemes can be implemented easily. We are discussing the general structure of the framework, some essential implementation details, and several proof-of-concept applications demonstrating the perspectives of the combined methods and the functionality of the toolkit. [ABSTRACT FROM AUTHOR]

We have measured reaction cross sections of neutron-rich 8Li nucleus on proton target at intermediate energies from 40.9 to 105.4 MeV/nucleon using the transmission method. Density distributions of 8Li are deduced by the use of the Glauber model to fit the experimental data. The matter and neutron radii converted from densities are consistent with other previous measurements. This work suggests that the measurement of the reaction cross section on the proton target can be a method to extract the neutron density distribution or neutron radius. [ABSTRACT FROM AUTHOR]

A labyrinth microstructure interconnected by micron and submicron acicular structures was successfully prepared by immersing nickel-aluminum bronze in 9 wt% FeCl3·6H2O solution at room temperature for 40 min. After being modified with 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane (FAS-17), the microstructure surface displays robustly low-adhesion superhydrophobicity, and the water contact angle is above 160 ° on it. In addition, the superhydrophobic surface exhibits excellent corrosion resistance and stability in 3.5wt % NaCl aqueous solution and corrosion solution with different pH values. [ABSTRACT FROM AUTHOR]

COVID-19 has impacted all spheres of life massively. Among the emerging studies on the psychosocial impact of the pandemic, few studies look specifically at how social workers are impacted. To understand this gap, this study surveyed 337 social workers. The findings showed that changes experienced in the workplace were enormous and caused secondary traumatic stress while engendering compassion satisfaction among social workers, but the presence of social support moderated to keep the secondary traumatic stress at bay. Resilience mediated association between social and workplace support and compassion fatigue. Social support seemed to have the largest effect on reducing stress through resilience. Workplace support also helped mitigate burnout. In conclusion, continued social and workplace support will be key to supporting social workers during a pandemic. [ABSTRACT FROM AUTHOR]

To investigate the therapeutic effect of anthracycline chemotherapy in advanced breast cancer and its influence on estradiol and tumor size, 136 breast cancer patients in Shan Xi Bethune Hospital were divided into anthracycline chemotherapy group and non-anthracycline chemotherapy group. The clinical effects of anthracycline chemotherapy group and non-anthracycline chemotherapy group were observed. The levels of estrone, estradiol and follicle stimulating hormone before and after treatment were measured. The tumor size, adverse reactions and 2-y survival rate of anthracycline chemotherapy group and non-anthracycline chemotherapy group were measured after 1-3 courses of treatment. The total effective rate of anthracycline chemotherapy group and non-anthracycline chemotherapy group was 64.7 and 23.5 %, respectively and the total effective rate of non-anthracycline chemotherapy group was significantly lower than that of anthracycline chemotherapy group (p<0.05). There was no significant difference in the comparison of serum estrone, estradiol and follicle stimulating hormone between the anthracycline chemotherapy group and non-anthracycline chemotherapy group (p<0.05). Compared to the anthracycline chemotherapy group, the level of serum estrone and estradiol in non-anthracycline chemotherapy group was significantly higher, compared to the non-anthracycline chemotherapy group, the level of serum follicle stimulating hormone in the anthracycline chemotherapy group was significantly higher (p<0.05). There was no significant difference in tumor size between the anthracycline chemotherapy group and non-anthracycline chemotherapy group (p>0.05). After treatment, the tumor volume of each group gradually decreased with increased time of drug exposure and the degree of tumor reduction in the non-anthracycline chemotherapy group was lower than that of the anthracycline chemotherapy group (p<0.05). Adverse reactions in both the groups were, the number of leucopenia cases in the anthracycline chemotherapy group was 14 while that in the non-anthracycline chemotherapy group was 17. The number of adverse reactions in the non-anthracycline chemotherapy group was more than that in the anthracycline chemotherapy group, but the difference was not significant (p>0.05). After 2 y of followup, the survival rate of anthracycline chemotherapy group was significantly higher than that of nonanthracycline chemotherapy group (p<0.05). The effect of anthracycline on advanced breast cancer was better, the level of serum estradiol decreased, and the volume of tumor decreased. [ABSTRACT FROM AUTHOR]

A model is developed to account for the viscous flow of glass-forming liquids. We consider that a supercooled glass-forming liquid is composed of a liquid phase and some solidlike clusters which have a higher activation energy for viscous flow than the liquid regions. This approach yields a fitting equation for viscosity with a simple form n = n[sub 0] exp(E/k[sub B]T)exp(ΦT/T[sub g]), where E is the activation energy for viscous flow at low temperatures, and Φ represents the fragility of a glass-forming system. Our results suggest that kinetic viscous flow of glass-forming liquids is closely related to their thermodynamics. [ABSTRACT FROM AUTHOR]

The influence of neutrons on charge changing cross-sections ( σ cc ) in C isotopes on 1 2 C and proton targets has been investigated in the framework of Glauber model. By comparing the theoretical results and experimental data, it is found out that the influence mainly comes from the projectile neutrons, and the σ cc has a slight change with the increase of the neutron number. Besides, the calculations also illustrate that the influence gets bigger with the reduction of the incident energy. [ABSTRACT FROM AUTHOR]

Abstract Most dynamic response analyses of rock slopes only consider the vertical incidence of seismic waves. However, obliquely incident waves dominate in near-field seismic areas. This paper presents a new seismic input method that considers near-field oblique incidence based on mechanisms of artificial viscous boundaries and the influence of incident angle on the dynamic response of rock slopes. Three numerical model slopes with different slope angles of 30°, 45° and 60° are excited with the El Centro earthquake record assuming varying incident angles from 0° to 90°. The results show that the incident angle significantly affects the dynamic response of the slopes. The most damaging incident directions are approximately perpendicular to the slope surface, rather than in the vertical direction. The dynamic response of the slopes will be underestimated if only the vertical incidence is considered. The incident angle affects the reflection wave field in the slope and the areas affected by the reflection waves decrease with increasing slope angle. However, the predominant period of the response spectrum of the rock slopes is not sensitive to the incident angle and location. This study unveils the dynamic mechanism of earthquake-induced rock slides, which is of significance for earthquake hazard prevention. Highlights • Oblique incident waves prevail in near-field seismic areas. • An input method for seismic response analysis including oblique incidence is developed. • The dynamic response of rock slopes will be underestimated if only the vertical incidence is considered. • Back slopes tend to respond more violently than face slopes do. • The most damaging incident direction is approximately perpendicular to the slope surface. [ABSTRACT FROM AUTHOR]

The Glauber model is modified with the Fermi-motion effect in the calculation of elastic differential cross-sections and momentum distributions of a fragment from mother nucleus. Different reaction systems at low energies are calculated with the modified Glauber model. It is found that calculations including the Fermi-motion provide a better prescription relating the model to a proper nuclear density distribution by comparing with the experimental data. On the basis of the studies, the influence of the correction on the extracted nuclear radius is quantified. The results further confirm the importance of the Fermi-motion in the nucleus-nucleus collision reactions at low energies. [ABSTRACT FROM AUTHOR]

Presents a study on the thermal stability of an amorphous alloy after various periods of low-energy ball milling by means of differential scanning calorimeter measurements. Factor affecting the mechanical deformation and irradiation effects on the structure of amorphous solids; Typical diffraction patterns for the amorphous alloy after various milling times; Reason for the enhanced thermal stability.

Reaction cross sections of 8Li on stable targets were measured at intermediate energies. With the existing experimental data of interaction cross sections at 790 MeV/nucleon the nucleón density distribution of 8Li was extracted by the use of the modified Glauber model. Meanwhile, the existing data of 8B have been also reanalyzed. Structures of 8Li and 8B were compared through the density. On the basis of dilute surface densities, the discussion of 7LÍ(H,K) 8Li and 7Be(p,y) 8B capture reactions was performed within the framework of the direct capture reaction mechanism. The calculations agreed quite well with the experimental data as well as other analyses. [ABSTRACT FROM AUTHOR]

The CRUNCEP V7 dataset was used to drive the Community Land Model version 4.5 (CLM4.5) to simulate the spatiotemporal changes in soil temperature in the Qinghai–Xizang Plateau from 1981 to 2016. The simulation results were compared with observations, ERA-Interim, and Global Land Data Assimilation System-Community Land Model (GLDAS-CLM) soil temperature reanalysis data. The results show that (1) the CLM4.5 can accurately reproduce the dynamic changes in the observed soil temperature over time in two soil layers (0–10 cm and 10–50 cm) at most sites, with a significant positive correlation with the observations. (2) The CLM4.5 can depict the spatial distribution of soil temperature in the plateau area, and the distribution characteristics are consistent with those of the reanalysis data. The soil temperature increases from north to south, and the values in the Qaidam Basin are significantly higher than those in the surrounding area. The CLM4.5 results are similar in value to the ERA-Interim product, while the GLDAS-CLM soil temperature values are generally higher. (3) The simulated value shows the trend of 'increasing–decreasing-increasing–decreasing' (+ − + −) from the west to the east in summer and autumn, while in winter and spring, the trend is generally increasing, but a decreasing trend is observed in some isolated locations. The temperature variation trends in the ERA-Interim data in winter and the GLDAS-CLM data in the middle of Sanjiangyuan in spring and the Qinghai Plateau in winter are consistent with those of the simulated data. The above results are all tested with 95% confidence. (4) From 1981 to 2016, the soil temperature on the plateau showed a significant upward trend, especially in spring and autumn. The two layers of the plateau have obvious seasonal changes, with the whole year characterised by a 'single peak shape'. From March to September, the shallow soil temperature is higher than the deep soil temperature, and from October to February, the deep soil temperature is higher than the shallow soil temperature. [ABSTRACT FROM AUTHOR]

We have precisely measured reaction cross sections (R) for 8Li using 9Be, 12C, 27Al, and proton targets at intermediate energies by the transmission method. From the energy dependence of the R including the high energy data, the density distribution of 8Li was deduced through a modified Glauber model. It is shown that 8Li has a shorter tail structure in the density as compared with that of 8B and the matter radius of 8Li is similar to those of the other nonhalo Li isotopes. The result is consistent with the previous experiments that there is a tendency for 8Li to be a skin nucleus. [ABSTRACT FROM AUTHOR]

A series of experiments have been carried out to investigate the direct melting reduction process of high phosphorus iron in a nitrogen atmosphere with non-isothermal heating. The weight loss factor of the iron ore can be considered as a function of the temperature in the reduction progress. The kinetic parameters of the model can be determined by the data in a single test with a non-isothermal heating rate. With the temperature increasing, the reduction process can be divided into decrystal water phase of limonite, the pre-reduced phase of hematite, and finally reduced phase. The final reduction can be divided into three sections. On this basis, functions of the reaction mechanism and apparent activation energy in each stage are expected to be investigated. Then, the compensation effect of the whole reaction process is presented. Finally, the relationship of apparent activation energy and pre-exponential factor are also analysed. [ABSTRACT FROM AUTHOR]

Equal channel angular pressing (ECAP) was performed on the extruded commercial pure magnesium at 250 °C for 4 passes. Heat treatments were carried out to modify the microstructures. The cyclic plastic deformation behavior of pure Mg with different grain sizes in microstrain region was studied by tensile loading and unloading experiments. The microplastic deformation process of pure Mg can be divided into two stages. In the first stage, pronounced plastic deformation associated with dislocation motion on basal plane is initiated at several MPa. The materials are softened and characterized by low friction stresses and hardening exponents. The microplastic deformation enters into region II above the strain of about 8 × 10. Annihilation and tangle of dislocations lead to the increase of hardening exponents and friction stresses. Pure Mg shows a very pronounced anelastic behavior during cyclic microplastic deformation, which results in a rapid increase of modulus defect, effectively decreasing the elastic modulus by up to 60 %. Grain size has a marked effect on microplastic deformation behavior of pure Mg. With increasing the grain size, the specimen shows a more pronounced microstrain and anelastic behavior. [ABSTRACT FROM AUTHOR]

Using the first-principles method based on the density functional theory, we have calculated electronic structure of zinc blende AlN doped with 6.25% of V. The V dopants are found spin polarized and the calculated band structures suggest a 100% polarization of the conduction carriers. The ferromagnetic ground state in V-doped AlN can be explained in terms of double-exchange mechanism, and a Curie temperature above room temperature can be expected. These results suggest that the V-doped AlN may present a promising dilute magnetic semiconductor and find applications in the field of spintronics. [ABSTRACT FROM AUTHOR]

Tantalum-doped indium tin oxide (Ta-doped ITO) transparent conductive films are deposited on glass substrates by electron-beam evaporation. The effects of different Ta concentrations and annealing temperatures on the structural, morphologic, electrical, and optical properties of Ta-doped ITO films are investigated by X-ray diffraction (XRD), atomic force microscope (AFM), Hall measurement, and optical transmission spectroscopy. The obtained films are polycrystalline with a cubic bixbyite structure of indium oxide and preferentially oriented in the (222) crystallographic direction. The minimum resistivity of 1.54×10-4 Ω ·cm is obtained from the ITO film containing 0.2 wt% tantalum annealed at 500°C and the average optical transmittance is over 95% from 425 nm to 460 nm. [ABSTRACT FROM AUTHOR]

Alloys exhibiting high damping capacity in ambient-temperature range (250–400K) are rare. Here it is reported that a martensitic alloy Ti–45Pd–5Cr shows twin-boundary-related high damping capacity over this temperature range. In the hydrogen-doped martensitic state, a relaxation-type high damping peak (Q −1 ≈0.09) exists, extending over 305–370K. In the hydrogen-free martensitic state, there is a fascinating high-damping plateau (Q −1 ≈0.05) over 250–450K. This work provides new insight into how to develop high damping alloys for the desired temperature range. [Copyright &y& Elsevier]

Equal channel angular pressing (ECAP) was performed on the extruded pure magnesium at 250°C for 4 passes. After ECAP processing, the grain size was significantly refined. And the damping capacity was increased at low strain amplitudes, but decreased at high strain amplitudes. Three peaks were observed during the measurement of damping capacity at elevated temperatures. The mechanisms for damping capacity of pure Mg at ambient and elevated temperatures were discussed. [ABSTRACT FROM AUTHOR]

First, the optical burst switching (OBS) network with limited wavelength conversion capability (LWCC) is decomposed into multiple wavelength continuous segments according to the position of wavelength converters. Based on the decomposed network model, two reservation signalling mechanisms for OBS-LWCC networks, namely wavelength-amend-on-demand (WAoD) and contention-based limited signalling protocol (CLSP), are proposed to reduce the blocking probability in the OBS-LWCC networks. In WAoD, the congested node sends a feedback message to the closest upstream switch with wavelength conversion capability. The notified switch will change the burst wavelength to the one assigned by the congested node to avoid collision in advance. Extensive simulation results indicate that by applying the wavelength reconfiguration method to the core nodes without wavelength conversion capability, the proposed WAoD scheme can improve the blocking performance in the OBS-LWCC networks significantly. Furthermore, CLSP, which combines the burst time-slot reconfiguration with the wavelength reconfiguration of WAoD, always has the lowest burst loss probability when compared with both the conventional and the proposed reservation mechanisms. [ABSTRACT FROM AUTHOR]

The prosurvival Bcl-2-family member Bfl-1/A1 is a transcriptional target of nuclear factor-κB (NF-κB) that is overexpressed in many human tumors and is a means by which NF-κB inhibits apoptosis, but its mode of action is controversial. To better understand how Bfl-1 functions, we investigated its interaction with proapoptotic multidomain proteins Bax and Bak, and the BH3-only proteins Bid and tBid. We demonstrate that in living cells Bfl-1 selectively interacts with Bak and tBid, but not with Bax or Bid. Bfl-1/Bak interaction is functional as Bfl-1 suppressed staurosporine (STS)-induced apoptosis in wild-type and Bax-deficient cells, but not in Bak−/− cells. We also show that Bfl-1 blocks tumor necrosis factor-α (TNFα)-induced activation of Bax indirectly, via association with tBid. C-terminal deletion decreased Bfl-1's interaction with Bak and tBid and reduced its ability to suppress Bak- and tBid-mediated cell death. These data indicate that Bfl-1 utilizes different mechanisms to suppress apoptosis depending on the stimulus. Bfl-1 associates with tBid to prevent activation of proapoptotic Bax and Bak, and it also interacts directly with Bak to antagonize Bak-mediated cell death, similar to Mcl-1. Thus, part of the protective function of NF-κB is to induce Mcl-1-like activity by upregulating Bfl-1.Oncogene (2008) 27, 1421–1428; doi:10.1038/sj.onc.1210771; published online 3 September 2007 [ABSTRACT FROM AUTHOR]

Abstract: Aim: To explore the presence of symptom clusters in patients with brain metastases. Materials and methods: Patients with brain metastases referred to an outpatient palliative radiotherapy clinic were asked to rate their symptom distress using the Edmonton Symptom Assessment Scale (ESAS). Baseline demographic data were obtained. To determine interrelationships between symptoms, a principal component analysis with ‘varimax rotation’ was carried out on the nine ESAS items. Follow-up was carried out by telephone 1, 2, 4, 8 and 12 weeks after radiation. Results: Between January 1999 and January 2002, 170 patients with brain metastases provided complete baseline data on the ESAS. The most common primary cancer sites were lung, breast and gastrointestinal. Fatigue was the highest scored symptom, followed by a poor sense of well-being, anxiety, drowsiness and poor appetite. The four most prevalent symptoms were fatigue (91.7%), a poor sense of well-being (88.1%), drowsiness (82.2%) and anxiety (82.1%). Three symptom clusters were found at baseline. Cluster 1 included fatigue, drowsiness, shortness of breath and pain. Cluster 2 included anxiety and depression. Cluster 3 included poor appetite, nausea and a poor sense of well-being. Fatigue, nausea, drowsiness and poor appetite showed an overall increase in symptom severity over time; whereas fatigue, drowsiness and poor appetite were experienced to some extent by a greater proportion of patients at week 12 compared with baseline. Symptom clusters emerged in all weeks of follow-up, but consisted of different symptoms in each week. Conclusion: Symptom clusters seemed to exist in patients with brain metastases before and after whole brain radiotherapy. However, different symptoms clustered at various time points. The effectiveness of whole brain radiotherapy in providing palliative relief to patients with brain metastases needs to be explored with regards to symptom clusters. [Copyright &y& Elsevier]

Abstract: Normally, martensitic transformation occurs in two stages (B2-R-B19′) in aged Ni-rich TiNi alloys. But a three-stage martensitic transformation was also reported. The origin of this abnormal transformation behavior has remained controversial, and in particular it is difficult to understand why in some cases the three-stage transformation occurs while in other cases normal two-stage transformation appears. Very recently by considering the kinetics features of Ti3Ni4 precipitation in polycrystalline Ni-rich TiNi, we propose a general mechanism, which is able to explain not only abnormal three-stage transformation but also normal two-stage transformation. In the present study, we made further experimental effort to critically verify the proposed mechanism by studying the transformation behavior of low Ni-rich polycrystals and intermediate Ni-rich polycrystals. We have found that low Ni-rich polycrystals exhibit three-stage transformation and the number of transformation peaks is independent of aging time; intermediate Ni-rich samples exhibit three-stage transformation after short time aging and two-stage transformation after longer time aging; but all the high Ni-rich samples show two-stage transformation, being independent of aging time. These results are consistent with our mechanism that different transformation behaviors are a result of competition between preferential grain boundary precipitation of Ti3Ni4 particles and a tendency for homogeneous precipitation when supersaturation of Ni is large. [Copyright &y& Elsevier]

Abstract: An abnormal three-stage martensitic transformation behavior (one-stage R and two-stage B19′) has been found in Ni-rich Ti–Ni alloys when aged at intermediate temperatures (350–500°C). This strange behavior was successfully explained by considering the kinetics of Ti3Ni4 precipitation in polycrystalline samples. However, it was found that R-phase transformation occurs in two stages, when aging is done at low temperatures (250–300°C). In order to find the origin of this abnormal phenomenon, we made a comparative study with Ni–49.4at.% Ti single crystals and polycrystals, which were aged at 250°C for different time. Differential scanning calorimetry showed that all single crystals undergo normal one-stage R-phase transformation, while polycrystals exhibit the abnormal two-stage R-phase transformation after short time aging. These different transformation behaviors can be understood by considering the kinetics of precipitation in supersaturated solid solution. The abnormal two-stage R-phase transformation is attributed to a large-scale heterogeneity of Ni-content between grain boundary region and grain interior, resulted from the preferential precipitation in grain boundary regions. Therefore, it is suggested that there is a unified scenario for seemingly different transformation behaviors of both low-temperature-aged and intermediate-temperature-aged Ti–Ni alloys. [Copyright &y& Elsevier]

Abstract: It is usually believed that there is an order–disorder transition at 1090°C in binary Ti–Ni alloys, as Honma et al. reported previously. The presence or absence of such transition is very important, because the result may greatly affect the martensitic transformation behavior, and the associated shape memory characteristics. In the present paper, we question whether such transition really exists or not. One of the difficulties in such experiments, including the work of Honma et al., lies in the fact that Ti can be easily oxidized at such high temperatures, which complicates the alloy behavior greatly and may lead to erroneous interpretation of experimental data. After doing carefully designed experiments on this point, we did not find any differential thermal analysis peak up to the melting temperature, or any drastic change in electrical resistance in a wide temperature region including 1090°C, which is the characteristic of order–disorder transition. These observations lead to the conclusion that such order–disorder transition does not exist in Ti–Ni binary shape memory alloys. [Copyright &y& Elsevier]

Abstract: The internal friction (IF) of Ti50Ni50−x Cu x polycrystals, which were normally solution-treated, was systematically studied using dynamic mechanical analysis. As a result, the broad peak appearing in B19 martensite was confirmed to be a relaxation peak with an activation energy of 0.67 and 0.76eV for x =20 and 16, respectively. Then the broad peak was shown to disappear in a single-crystal experiment, if twin boundaries in martensite are largely eliminated. This is direct evidence to show twin boundaries are indispensable for the broad peak. The effect of hydrogen on IF was also examined using a vacuum system with a mass spectrometer, and the broad peak at 250K was observed to disappear, while a new small relaxation peak was found at 178K, when hydrogen was eliminated. These experiments clearly show that there are two essential ingredients to observe the high broad peak: twin boundaries and hydrogen. Based on these results a possible origin for the broad peak is discussed. [Copyright &y& Elsevier]

A numerical analysis is presented about the performance of non-collinear acousto-optic interaction in LiNbO3 guiding structures. To get the optimal design for a higher diffraction, the SAW power required for 100% diffraction (P100) dependences on the length of acousto-optic (AO) interactions, guided optical mode, waveguide depth and driving frequency are investigated. Some valuable results are obtained for design of guided-wave acousto-optic devices. [ABSTRACT FROM AUTHOR]

A computer model of overlap integral is presented in abnormal guided acoustooptic interaction using mode conversion. Overlap integral of LiNbO3 is analyzed for TE↔TM polarized light in abnormal acoustooptic interaction with different penetration depths. Some valuable results are obtained for design of acoustooptic devices. [ABSTRACT FROM AUTHOR]

Laboratory tests were conducted to simultaneously measure soil water content and salinity using a four-electrode Wenner array sensor. The sensor was modified to enhance the capacitive effect. Soil bulk density and the depth to which the electrodes penetrate into the soil were strictly controlled during the experiments. Sinusoidal current signals with a constant amplitude and frequencies ranging from 1 Hz to 15 MHz were sent to the outer electrodes of the Wenner array, whereas voltage outputs were measured from the inner electrodes. Frequency-response data were analyzed using the partial least-squares method to establish calibration models for simultaneously predicting water content and salinity from the frequency-response patterns. The R² values for predicting water content and salinity at the 30-mm penetration depth reached 0.89 and 0.91, respectively, whereas the root-mean-square errors for the volumetric water content and salinity measurements were 0.019 m³ m-3 and 0.173 cmol kg-1, respectively. Test results showed that, in general, the calibration models predicted the water content more accurately than salinity. The depth to which the sensor penetrates into the soil has a strong effect on the measurement accuracy. This study has demonstrated that the modified Wenner array sensor and the frequency-response method have a potential for simultaneously measuring soil capacitive and conductive properties. However, numerous difficulties, including contact resistance, depth control, and the effect of soil type, will need to be addressed to improve the measurement accuracy. [ABSTRACT FROM AUTHOR]

The correlation between the temperature dependence of the kinetic and thermodynamic properties of a series of metallic glass-forming liquids is investigated using the concept of fragility. The results indicate a correlation between the kinetic fragility and thermodynamic fragility in these liquids. The correlation depends critically on the approach used to evaluate the thermodynamic fragility. Two distinct correlation lines are found for the metal-metalloid and for the all-metallic-constituents glass-forming liquids. For the same thermodynamic fragility the metal-metalloid liquids exhibit a distinctively larger kinetic fragility than the pure-metallic liquids. From the evaluation of the Gibbs free-energy difference between the undercooled liquid and the crystalline phase mixture, a correlation between the kinetic fragility and the driving force for nucleation is found, showing that for glass formation in metallic alloys the thermodynamic and kinetic contributions act together. [ABSTRACT FROM AUTHOR]

The digital revolution currently under way, as evidenced by the rapid development of the Internet and the world-wideweb technologies, is undoubtedly impacting the field of transmission electron microscopy (TEM). Digital imaging systems based on charge-coupled device (CCD) technologies, with pixel array size up to 2 k x 2 k at the present and increasing, are available for TEM applications and offer many attractions. Is it time to phase out film cameras on TEMs and close the darkrooms for good? This paper reviews digital imaging technologies for TEM at different voltages, and contrasts the performance of digital imaging systems with that of TEM film. The performance characteristics of CCD-based digital imaging systems, as well as methods for assessing them, are discussed. Other approaches to digital imaging are also briefly reviewed. [ABSTRACT FROM AUTHOR]

To develop and validate a deep learning (DL) algorithm for the automated detection and classification of carotid artery plaques (CAPs) on computed tomography angiography (CTA) images. This retrospective study enrolled 400 patients (300 in the Center Ⅰ and 100 in Ⅱ). Three radiologists co-labeled CAPs, and their revised calcification status (noncalcified, mixed, and calcified) was regarded as ground truth. Center Ⅰ patients were randomly divided into training and internal validation datasets, while Center Ⅱ patients served as the external validation dataset. Carotid artery regions were segmented using a modified 3D-UNet network, followed by CAPs detection and classification using a ResUNet-based architecture in a two-step DL system. The DL model's detection and classification performance were evaluated on the validation dataset using precision-recall curve, free-response receiver operating characteristic (fROC) curve, Cohen's kappa, and ROC curve analysis. The DL model had achieved 83.4% sensitivity at 3.0 false positives (FPs)/CTA scan in internal validation and 78.9% in external validation. F1-scores were 0.764 and 0.769 at the optimal threshold, and area under fROC curves were 0.756 and 0.738, respectively, indicating good overall accuracy for CAP detection. The DL model also showed good performance for the ternary classification of CAPs, with Cohen's kappa achieved 0.728 and 0.703 in both validation datasets. This study demonstrated the feasibility of using a fully automated DL-based algorithm for the detection and ternary classification of CAPs, which could be helpful for the workloads of radiologists. • The research focuses on automatic classification of CAP. • The DL model can achieve good performance in CAP detection and classification. • The DL model could be applied to deal with reporting workload in the acute setting. [ABSTRACT FROM AUTHOR]

By employing a containerless high-temperature high-vacuum electrostatic levitation technique, the thermophysical properties, including the ratio between the specific heat capacity and the hemispherical total emissivity, the specific volume, and the viscosity, of Cu50Zr50 and (Cu50Zr50)95Al5 bulk-metallic-glass (BMG)-forming liquids have been measured. Compared with Cu50Zr50, the improved glass-forming ability of (Cu50Zr50)95Al5 can be attributed to its dense liquid structure and its high value of viscosity. Additionally, the relationship between the viscosity of various BMG forming liquids at the melting temperature and the elastic properties of the corresponding glasses at room temperature will be compared. [ABSTRACT FROM AUTHOR]

By employing a high-energy x-ray diffraction technique, the authors report that uniaxial tensile plastic deformation induced the grain growth and texture development in a bulk nanocrystalline Ni–Fe alloy. The effects become more pronounced with increasing the plastic strain (closer to the fracture surface). The texture development accompanying the grain rotation indicates that dislocation motion contributed to the observed plasticity in the nanocrystalline Ni–Fe alloy. The quantitative experimental data suggest that the dislocation storage was absent in the uniformly deforming region; whereas the dislocation storage was present in the necking region, where the grain growth was substantial. [ABSTRACT FROM AUTHOR]

The effect of room-temperature aging on the mechanical behaviors of an electrodeposited bulk nanocrystalline (nc) Ni–Fe alloy has been investigated. The tensile elongation to failure, [variant_greek_epsilon]f, of the bulk nc Ni–Fe alloy decreased from approximately 7.2% in the as-deposited state to 5.0%, after aging at room temperature for one year. Moreover, the fatigue-endurance limit decreased from about 260 to 190 MPa. This aging-induced embrittlement may be mainly due to the enhanced atomic diffusivity in the nc materials, leading to the segregation of the impurity atoms at the grain boundaries. [ABSTRACT FROM AUTHOR]

The thermophysical properties, including the specific volume V, the surface tension σ, and the viscosity η, of a Cu46Zr42Al7Y5 bulk metallic glass in the molten state were investigated using a containerless high-temperature high-vacuum electrostatic levitation technique. The viscosity measurements indicate that the Cu46Zr42Al7Y5 alloy exhibits an intermediate fragility with the fragility index m=49. [ABSTRACT FROM AUTHOR]

The microstructural evolution during the uniaxial compression of an as-deposited bulk nanocrystalline (nc) Ni–Fe (average grain size d≈23 nm) at ambient temperature was investigated by the high-energy x-ray diffraction (HEXRD) and the transmission-electron microscopy (TEM). HEXRD measurements indicated that the grain growth occurred in the nc Ni–Fe alloy during the uniaxial compression tests and that the grain growth shows orientation dependence, i.e., the grains preferentially grow perpendicular to the loading direction. This preferred grain growth was further confirmed by the TEM observations, indicating that the grains were elongated after the compressive plastic deformation. [ABSTRACT FROM AUTHOR]

The equilibrium viscosity of the Pd[sub 43]Ni[sub 10]Cu[sub 27]P[sub 20] bulk metallic glass-forming liquid was measured over a wide temperature range from the equilibrium supercooled liquid state to the glass transition region using parallel-plate rheometry and three-point beam bending. Based on the measured viscosity data, the fragility of this liquid was quantitatively determined. The Pd[sub 43]Ni[sub 10]Cu[sub 27]P[sub 20] alloy, despite exhibiting the best glass-forming ability reported thus far, is relatively fragile compared with other bulk glass-forming liquids, such as Vit 1 and Vit 4. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The experiment was conducted to investigate the protective effect of Smilax glabra Roxb. aqueous extract on carbon tetrachloride induced acute liver injury in rats by regulating the nucleotide binding leucine rich repeat receptors family pyrin domain containing 3 inflammasome. In this study, a rat acute liver injury model was established by a single intraperitoneal injection of 50 % carbon tetrachloride oil solution (1 ml/kg body weight). A total of 50 rats were randomly divided into control group, model group and 3 Smilax glabra Roxb. aqueous extract intervention groups (0.75, 1.5 and 3 g/kg body weight/d). Smilax glabra Roxb. aqueous extract or distilled water was orally administered by gavage once daily for seven consecutive days. Then the blood and liver samples were collected. The results showed that in the 3 intervention Smilax glabra Roxb. aqueous extract groups, the levels of serum aspartate aminotransferase and Alanine aminotransferase, the content of malondialdehyde in rat liver tissues significantly reduced and superoxide dismutase, catalase and glutathione increased significantly, the liver lobule structures were repaired and the liver cells were aligned in an orderly manner, the expressions of nucleotide binding leucine rich repeat receptors family pyrin domain containing 3 inflammasome, apoptosis associated speck like protein containing and caspase-1 proteins, Interleukin 1 beta messenger ribonucleic acid was decreased. Smilax glabra Roxb. aqueous extract exerted a protective effect against carbon tetrachloride induced acute liver injury by inhibiting the activation of nucleotide binding leucine rich repeat receptors family pyrin domain containing 3 inflammasome, which suggest a promising avenue for the exploration of Smilax glabra Roxb. aqueous extract in improving acute liver injury. [ABSTRACT FROM AUTHOR]

Background: Minimal erythema dose (MED) has substantial inter‐ and intraindividual variations, reflecting the influence of very diverse factors. However, related studies showed little consistency probably because of their limited sample size. Objective: To identify the factors associated with MED variations in a large‐scale population study. Methods: The MED test was performed by following the international standard procedure on 22 146 subjects. The results were analysed in adjusted multivariable linear and logistic regression models. Results: This large‐scale study revealed that lower MED was consistently associated with lighter skin [β‐coefficient = −0.33, 95% confidence interval (CI) −0.36 to 0.30, P = 6.41 × 10−84]. Females had significantly higher MED than male (β = 0.91, 0.32–1.50, P = 2.93 × 10−3). Stratified analyses showed that MED was not associated with age [female: odds ratio (OR) = 0.99, 0.98–1.01; male: OR = 0.99, 0.97–1.00]. MED was lower in summer than in other seasons (spring: OR = 1.08, 1.06–1.11; autumn: OR = 1.11, 1.08–1.13; winter: OR = 1.20, 1.18–1.22). Furthermore, MED was associated with air temperature (β = −0.36, −0.49 to 0.23, P = 4.81 × 10−8) and air pressure (β = −0.64, −0.82 to 0.46, P = 8.01 × 10−12) in summer only while not in other seasons. Conclusions: This study provides unprecedented evidence that MED is associated with skin colour, sex, season and meteorological factors, but not with age. [ABSTRACT FROM AUTHOR]

Aims: The outer membrane porin protein (OMPP) of Bordetella bronchiseptica is an important adhesion factor and protective immunogen. The aim of this study was to verify the immunogenicity of recombinant OMPP and its protective efficacy against a lethal challenge with B. bronchiseptica in rabbits. Methods and Results: Soluble rOMPP was successfully expressed in Escherichia coli, and the purified recombinant protein was mixed with the ISA 201 VG adjuvant to prepare a subunit vaccine for B. bronchiseptica. Rabbits were immunized with the rOMPP subunit vaccine and then infected with the virulent B. bronchiseptica strain QDBb01. Rabbits immunized with the subunit vaccine were completely protected compared to the control group, and the protective effect was obviously better than that of the inactivated whole‐cell vaccine. Moreover, analysis of the immunization duration showed that the rOMPP subunit vaccine provided immune protection for at least 4 months after the second immunization. Conclusions: The rOMPP subunit vaccine completely protected rabbits from a subsequent B. bronchiseptica challenge. Significance and Impact of the Study: The results will provide key information for the development of a safe and effective recombinant subunit vaccine against B. bronchiseptica in rabbits. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the differences between patients with Parkinson's disease (PD) and Parkinson variant of multiple system atrophy (MSAp) at fractional anisotropy (FA) in the white matter when using the tract-based spatial statistics (TBSS) algorithm to provide objective markers for a differential diagnosis.Materials and Methods: Diffusion-tensor imaging (DTI) data were acquired from 18 PD patients, 20 MSAp patients, and 24 healthy controls using a GE 3 T Signa HDx magnetic resonance imaging (MRI) system. The hypothesis-free whole-brain analysis (TBSS), focusing on global white matter microstructural deterioration, was adopted based on comparison among groups. Furthermore, regions of interest (ROIs) were drawn on the major fibre bundles showing abnormalities in TBSS.Results: In the MSAp group, FA values significantly decreased in the middle cerebellar peduncle (MCP), pontine crossing tract, and corticospinal tract bilaterally. In the PD group, FA values significantly decreased in multiple supratentorial areas including the corpus callosum (CC), fornix, and left hippocampus.Conclusion: DTI may be an effective tool to discover pathological differences between MSAp and PD. To substantially assist the non-invasive differential diagnosis of MSAp and PD, FA measurements should not only be limited to the MCP but also the CC. [ABSTRACT FROM AUTHOR]

The primary objective was to evaluate whether a molecular point-of-care test (POCT) for viral and atypical pathogens added to routine real-time PCR could reduce duration of intravenous antibiotics in hospitalized patients with lower respiratory tract infection (LRTI) compared with routine real-time PCR. In this single-centre, open-label, randomized controlled study, we enrolled hospitalized adults diagnosed with LRTI. Patients were randomized to an intervention group (POCT FilmArray Panel for 20 viruses, atypical pathogens and bacteria plus routine real-time PCR) or a control group (routine real-time PCR for ten pathogens). The primary outcome was duration of intravenous antibiotics during hospitalization. The secondary outcomes included length of stay, cost of hospitalization and de-escalation within 72 hours and between 72 hours and 7 days. Intention-to-treat analysis was used. Between October 2017 and July 2018, we enrolled 800 eligible patients (398 in the intervention group and 402 in the control group). Duration of intravenous antibiotics in the intervention group was shorter than in the control (7.0 days (interquartile range (IQR) 5.0–9.0) versus 8.0 days (IQR 6.0–11.0); p <0.001). Length of hospital stay in the intervention group was significantly shorter (8.0 days (IQR 7.0–11.0) versus 9.0 days (IQR 7.0–12.0; p <0.001) and the cost of hospitalization in the intervention group was significantly lower ($1804.7 (IQR 1298.4–2633.8) versus $2042.5 (IQR 1427.4–2926.2); p 0.002) than control group. More patients in the intervention group achieved de-escalation within 72 hours (7.9%, 29/367 versus 3.2%, 12/377; p 0.005) and between 72 hours and 7 days (29.7%, 109/367 versus 22.0%, 83/377; p 0.024). Use of molecular POCT testing for respiratory viruses and atypical pathogens might help to reduce intravenous antibiotic use in hospitalized LRTI patients. clinicaltrials.gov Identifier: NCT03391076. [ABSTRACT FROM AUTHOR]

Micro-channels have been widely used in variety of devices including bipolar plate, micro-chemical reactor, and micro-heat pipe. Electrochemical machining (ECM) is a promising approach to manufacture such structure on metallic surface. This paper proposed a modified jet-ECM for generating micro-channels. A flexible insulated mask with micro-through-holes was covered on the head surface of a metallic nozzle. During machining, the mask on the modified nozzle was contacted with the workpiece, and the jetting electrolyte in the nozzle was divided into different machining regions by the micro-through-holes in the mask; then, the micro-channels could be generated by moving the workpiece with an effective voltage applied between the nozzle and workpiece. Compared with traditional jet-ECM, the machining region in this method could be confined by the micro-through-hole, which was efficient for generating channel in micro-scale. In addition, multiple micro-channels could be generated by using a mask with a single row of micro-through-holes rather than assembling multiple nozzles. The experimental results showed that the pulse duty cycle has a significant influence on the dimension of micro-channel, while the pulse frequency has slight influence in contrast. In addition, the material removal rate (MRR), effective material removal rate (MRRe), and current efficiency (CE) were investigated with different machining parameters. The results indicated that although MRR was increased with the increasing pulse duty cycle, both MRRe and CE were reduced, leading to a deviation between the theory and experiment. The moving speed of workpiece also has a significant influence on CE. Increasing moving speed was useful for enhancing the CE, from 0.48 to 0.66 with the moving speed increasing from 20 to 80 μm/s. Finally, several kinds of micro-channels such as multiple micro-channels, micro-reactor, and cross micro-channels were well manufactured with this method, demonstrating a flexible and efficient process. [ABSTRACT FROM AUTHOR]

The microstructure and mechanical properties of the extruded Mg–2Gd–1.2Y–0.5Zn (at.%) alloy with Mn or Zr addition were investigated. The results show that Zr addition refines the microstructure of the homogenized alloy more efficiently and facilitates the dissolution of the secondary phases in comparison with Mn addition. After extrusion at 400 °C, both Mn and Zr added alloys exhibit bimodal microstructure comprising fine dynamically recrystallized (DRXed) grains with random orientations as well as coarse unDRXed grains with strong 10 1 ¯ 0 //ED fiber texture. Thin long period stacking ordered phases and γ precipitates distribute in the unDRXed grains and nano-sized β phases mainly pin at the DRXed grain boundaries. While the coarse initial grain size of homogenized Mn added alloy leads to its lower DRX ratio and stronger texture intensity after extrusion with respect to Zr added alloy. High strength, moderate ductility and improved yield anisotropy are obtained in both extruded alloys. The Mn added alloy exhibits higher strength with ultimate tensile strength of 437 MPa, 0.2% tensile proof stress of 381 MPa but lower elongation to failure of 4.7% than Zr added alloy, which is mainly due to the lower DRX ratio of Mn added alloy. [ABSTRACT FROM AUTHOR]