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Purpose: To assess the pharmacokinetics and pharmacodynamics of linezolid in a retrospective cohort of hospitalized Chinese older patients. Methods: Patients > 60 years of age, who received intravenous linezolid (600 mg), were included. A population pharmacokinetics (PPK) model was established using nonlinear mixed-effects modeling. The predictive performance of the final model was assessed using goodness-of-fit plots, bootstrap analyses, and visual predictive checks. Monte Carlo simulations were used to evaluate the achievement of a pharmacodynamics target for the area under the serum concentration–time curve/minimum inhibitory concentration (AUC0–24/MIC). Results: A total of 210 samples were collected from 120 patients. A one-compartment PPK model with linear elimination best predicted the linezolid plasma concentrations. Linezolid clearance (CL) was 4.22 L h−1 and volume of distribution (Vd) was 45.80 L; serum uric acid (SUA) was a significant covariate of CL. Conclusion: The results of this study indicated that the standard dose was associated with a risk of overexposure in older patients, particularly those with high SUA values; these patients would benefit from a lower dose (300 mg every 12 h). [ABSTRACT FROM AUTHOR]

This paper presents a method for minimizing the power consumption of a data-center cooling system by optimizing the airflow pattern and the supplied cold air temperature simultaneously. To discover the potential benefits of reorganizing the rack flow rates, a gray-box fast-temperature evaluation model is proposed for the first time, which reflects the thermal relationship among the components of the data center and has low computational complexity. Next, a model-based constrained nonlinear optimization problem is formulated with the aim of minimizing the power consumption of both cooling fans and air conditioners. Meanwhile, the safety thermal guidelines are considered as the main constraints. At last, the optimal settings of rack airflow rates and supplied cold air temperature are obtained by solving the optimization problems. The simulation results show that the proposed method can yield an effective thermal management tool and reduce significant cooling power for air-cooled data centers. [ABSTRACT FROM AUTHOR]

The management and protection of forest resources has become one of the major issues of environmental protection globally. As the largest developing country in the world, China has determined that the construction of an ecological civilization is an important piece of a millennium plan for China's sustainable development. The ecological capital theory, which adheres to the idea of a harmonious coexistence between man and nature, provides an opportunity to open up a new chapter for the construction of ecological civilization. Based on the fact China is a country endowed with unique resources, this paper aims to provide a theoretical reference on how to maximize the value of forest ecological resources and promote the sustainable development of global forest resources. To gain clear insights, this paper uses the theory of ecological capital to discuss how to demarcate the concept of the capitalization of forest ecological resources. The internal motivation of the capitalization of forest ecological resources was analysed from two perspectives: how to keep the balance between ecological protection and resource development, and how people have changed the way of using forest resources. This paper has expounded how forest ecological resources are transformed to forest ecological assets and then forest ecological capital, indicating the realization path of the capitalization of forest ecological resources, that is, a direct utilisation of forest resources and indirect new ways of forestry management. It aims to provide theoretical references for maximizing the value of forest ecological resources and achieving the sustainable development of global forest resources. [ABSTRACT FROM AUTHOR]

Summary: The C2H2‐type zinc finger transcription factor sensitive to proton rhizotoxicity 1 (STOP1) is crucial for aluminum (Al) resistance in Arabidopsis. The F‐box protein Regulation of AtALMT1 Expression 1 (RAE1) was recently reported to regulate the stability of STOP1. There is a unique homolog of RAE1, RAH1 (RAE1 homolog 1), in Arabidopsis, but the biological function of RAH1 is still not known. In this study, we characterize the role of RAH1 and/or RAE1 in the regulation of Al resistance and plant growth. We demonstrate that RAH1 can directly interact with STOP1 and promote its ubiquitination and degradation. RAH1 is preferentially expressed in root caps and various vascular tissues, and its expression is induced by Al and controlled by STOP1. Mutation of RAH1 in rae1 but not the wild‐type (WT) background increases the level of STOP1 protein, leading to increased expression of STOP1‐regulated genes and enhanced Al resistance. Interestingly, the rah1rae1 double mutant shows reduced plant growth compared with the WT and single mutants under normal conditions, and introduction of stop1 mutation into the double mutant background can rescue its reduced plant growth phenotype. Our results thus reveal that RAH1 plays an unequally redundant role with RAE1 in the modulation of STOP1 stability and plant growth, and dynamic regulation of the STOP1 level is critical for the balance of Al resistance and normal plant growth. Significance Statement: The zinc finger transcription factor sensitive to proton rhizotoxicity 1 (STOP1) is crucial for aluminum resistance in Arabidopsis. Whether RAH1, the unique homolog of the F‐box protein RAE1, plays a role in STOP1 degradation and whether STOP1 degradation is beneficial for plant growth are still unknown. We demonstrate that RAH1 plays an unequally redundant role with RAE1 in STOP1 degradation and dynamic regulation of the STOP1 level is critical for the balance of aluminum resistance and normal plant growth. [ABSTRACT FROM AUTHOR]

Aluminum (Al) is a primary constraint for crop production on acid soils, which make up more than 30% of the arable land in the world. Al resistance in Arabidopsis (Arabidopsis thaliana) is achieved by malate secretion mediated by the Al-ACTIVATED MALATE TRANSPORTER1 (AtALMT1) transporter. The C2H2-type transcription factor SENSITIVE TO PROTON RHIZOTOXICITY1 (STOP1) is essential and required for Al resistance, where it acts by inducing the expression of Al-resistance genes, including AtALMT1. In this study, we report that STOP1 protein function is modified by SUMOylation. The SMALL UBIQUITIN-LIKE MODIFIER (SUMO) protease ESD4, but not other SUMO proteases, specifically interacts with and deSUMOylates STOP1. Mutation of ESD4 increases the level of STOP1 SUMOylation and the expression of the STOP1-regulated gene AtALMT1 , which contributes to the increased Al resistance in esd4. The esd4 mutation does not influence STOP1 protein abundance but increases the association of STOP1 with the AtALMT1 promoter, which might explain the elevated expression of AtALMT1 in esd4. We demonstrate that STOP1 is mono-SUMOylated at K40, K212, or K395 sites, and blocking STOP1 SUMOylation reduces STOP1 stability and the expression of STOP1-regulated genes, leading to the reduced Al resistance. Our results thus reveal the involvement of SUMOylation in the regulation of STOP1 and Al resistance in Arabidopsis. [ABSTRACT FROM AUTHOR]

The thermal predicting/evaluating model of data centers is pivotal in designing their thermal control systems. The existing modeling methods are based on the computational fluid dynamics (CFD) simulations, which is accurate in modeling for a steady-state flow pattern but considerably time-consuming. Besides, the corresponding parameters of CFD have to be re-identified with the deviation of the flow field, which makes it extremely inefficient in real-time thermal control system design of data centers. This paper proposed a machine learning method to derive the fast-temperature evaluation model with a constructed artificial neural network. It learns the relationship between the flow patterns and model parameters based on the system thermal–physical analysis, which replaces the time-consuming CFD-based parameter identifying process. Then, the temperature evaluation is implemented under different flow patterns with the proposed neural-network enhanced modeling method. In the learning process, multi-type of neural networks, i.e., backpropagation network, radial basis function network and extreme learning machine, are considered and compared. The accuracy of the proposed model is validated by comparing with the pure CFD results as the satisfactory standard. With the efficiency and accuracy, the proposed modeling method is more suitable to design real-time controllers for data centers with changing flow fields. [ABSTRACT FROM AUTHOR]

In the present paper, different electronic structure methods have been used to determine stationary and intersection structures on the ground (S0) and 1ππ* (S2) states of 4-methylpyridine, which is followed by adiabatic and nonadiabatic dynamics simulations to explore the mechanistic photoisomerization of 4-methylpyridine. Photoisomerization starts from the S2(1ππ*) state and overcomes a small barrier, leading to formation of the prefulvene isomer in the S0 state via a S2/S0 conical intersection. The ultrafast S2 → S0 nonradiative decay and low quantum yield for the photoisomerization reaction were well reproduced by the combined electronic structure calculation and dynamics simulation. The prefulvene isomer was assigned as a long-lived intermediate and suggested to isomerize to 4-methylpyridine directly in the previous study, which is not supported by the present calculation. The nonadiabatic dynamics simulation and electronic structure calculation reveal that the prefulvene isomer is a short-lived intermediate and isomerizes to benzvalene form very easily. The benzvalene form was predicted as the stable isomer in the present study and is probably the long-lived intermediate observed experimentally. A consecutive light and thermal isomerization cycle via Dewar isomer was determined and this cycle mechanism is different from that reported in the previous study. It should be pointed out that formation of Dewar isomer from the S2(1ππ*) state is not in competition with the isomerization to the prefulvene form. The Dewar structure observed experimentally may originate from other excited states. [ABSTRACT FROM AUTHOR]

The potential energy surfaces for Cl2CO dissociation into CO+Cl+Cl in the lowest two electronic singlet states (S0 and S1) have been determined by the complete active space self-consistent field, coupled-cluster method with single and double excitations (CCSD), and equation-of-motion CCSD calculations, which are followed by direct ab initio molecular dynamics simulations to explore its photodissociation dynamics at 230 nm. It is found that the C–O stretching mode is initially excited upon irradiation and the excess internal energies are transferred to the C–Cl symmetric stretching mode within 200 fs. On average, the first and the second C–Cl bonds break completely within subsequent 60 and 100 fs, respectively. Electronic structure and dynamics calculations have thus provided a strong evidence that the photoinitiated dissociation of Cl2CO at 230 nm or shorter wavelengths is an ultrafast, adiabatic, and concerted three-body process. Since the two C–Cl bonds begin to break at the same time and the time interval between the two C–Cl bond broken fully is very short (∼40 fs), the photoinitiated dissociation of Cl2CO to CO+2Cl can be considered as the synchronous concerted process. [ABSTRACT FROM AUTHOR]

Double-sampling schemes using one classifier assessing the whole sample and another classifier assessing a subset of the sample have been introduced for reducing classification errors when an infallible or gold standard classifier is unavailable or impractical. Inference procedures have previously been proposed for situations where an infallible classifier is available for validating a subset of the sample that has already been classified by a fallible classifier. Here, we consider the case where both classifiers are fallible, proposing and evaluating several confidence interval procedures for a proportion under two models, distinguished by the assumption regarding ascertainment of two classifiers. Simulation results suggest that the modified Wald-based confidence interval, Score-based confidence interval, two Bayesian credible intervals, and the percentile Bootstrap confidence interval performed reasonably well even for small binomial proportions and small validated sample under the model with the conditional independent assumption, and the confidence interval derived from the Wald test with nuisance parameters appropriately evaluated, likelihood ratio-based confidence interval, Score-based confidence interval, and the percentile Bootstrap confidence interval performed satisfactory in terms of coverage under the model without the conditional independent assumption. Moreover, confidence intervals based on log- and logit-transformations also performed well when the binomial proportion and the ratio of the validated sample are not very small under two models. Two examples were used to illustrate the procedures. [ABSTRACT FROM AUTHOR]

A model predictive control (MPC) method is presented for the optimizing energy consumption of Internet data centers at the same time maintaining the quality of service (QoS). A dynamical model reflecting computational interactions and thermal relationship between each components of the data center is presented. The model is used to formulate a constrained nonlinear optimal control problem to minimize the energy consumption of both information technology system and cooling technology system. The constraints of this optimal control problem can capture key design requirements, including QoS and thermal constraints for device reliability. Solving this optimal control problem in MPC fashion provides optimal server provisioning, job scheduling, and thermal management techniques that meet specific desired service quality requirements. To reduce the computational delay in solving the constrained nonlinear optimization problem, an approximation algorithm is developed to provide a fast evaluation of complex constrains. The performance of the proposed method is studied through simulations. The results show that significant energy saving can be achieved with the guaranteed throughput of data center. [ABSTRACT FROM PUBLISHER]

A considerable proportion of Masson pine forests have been converted into eucalypt plantations in the last 30 years in Guangdong Province, subtropical China, for economic reasons, which may affect the ammonia-oxidizing archaea (AOA) community and the process of ammonia transformation. In order to determine the effects of forest conversion on AOA community, AOA communities in a Masson pine ( Pinus massoniana) plantation and a eucalypt ( Eucalyptus urophylla) plantation, which was converted from the Masson pine, were compared. Results showed that the land use change from the Masson pine to the eucalypt plantation decreased soil nutrient levels. A significant decrease of the potential nitrification rates (PNR) was also observed after the forest conversion ( p < 5 %, n = 6). AOA were the only ammonia oxidizers in both plantations (no ammonia-oxidizing bacteria were detected). The detected AOA are affiliated with the genera Nitrosotalea and Nitrososphaera. A decrease of AOA abundance and an increase of the diversity were evident with the plantation conversion in the surface layer. AOA amoA gene diversity was negatively correlated with organic C and total N, respectively ( p < 0.05, n = 12). AOA amoA gene abundance was negatively correlated with NH and available P, respectively ( p < 0.05, n = 12). However, AOA abundance was positively correlated with PNR, but not significantly ( p < 0.05, n = 6), indicating AOA community change was only a partial reason for the decrease of PNR. [ABSTRACT FROM AUTHOR]

A simple, efficient, and eco-friendly aerobic procedure for synthesis of 2-substituted benzothiazoles catalyzed by facile prepared [N][Pro] in a biomass medium (ethyl lactate) has been developed. The reactions afford the target 2-arylbenzothiazoles in good to excellent yields (>80 %) under air condition and was observed without use of chromatography. In addition, this proline-based ionic liquid catalyst can be easily recycled six times without loss of catalytic activity in gram scale synthesis. [ABSTRACT FROM AUTHOR]

Segmentation, which is usually the first step in object-based image analysis (OBIA), greatly influences the quality of final OBIA results. In many existing multi-scale segmentation algorithms, a common problem is that under-segmentation and over-segmentation always coexist at any scale. To address this issue, we propose a new method that integrates the newly developed constrained spectral variance difference (CSVD) and the edge penalty (EP). First, initial segments are produced by a fast scan. Second, the generated segments are merged via a global mutual best-fitting strategy using the CSVD and EP as merging criteria. Finally, very small objects are merged with their nearest neighbors to eliminate the remaining noise. A series of experiments based on three sets of remote sensing images, each with different spatial resolutions, were conducted to evaluate the effectiveness of the proposed method. Both visual and quantitative assessments were performed, and the results show that large objects were better preserved as integral entities while small objects were also still effectively delineated. The results were also found to be superior to those from eCongnition's multi-scale segmentation. [ABSTRACT FROM AUTHOR]

The development of near-infrared spectroscopy(NIRS) realizes the continuous, real-time, rapid and non-traumatic detection of skeletal muscle oxygen saturation(SmO2). SmO2 can be thought of as a measure of the balance between supply and demand for oxygen in the muscle. The measurement of SmO2 takes place in the capillaries of the muscle. SmO2, electromyography (EMG) and heart rate (HR) have obvious changes when enduring incremental testing. But the relationship of them is still unclear. PURPOSE: To investigate SmO2, electromyography (EMG), HR and the relationship among them. Trying to provide a theoretical and practical reference for sports training. METHODS: The trial group included 12 male students from Beijing Sport University. Participants did incremental exercises on a bicycle ergometer, load began at 50 watts and increased 50 watts every 3 minutes until they exhausted. We detected the SmO2 and EMG of vastus lateralis by MOXY muscle monitor and DELSYS Trigno wireless system. Remote monitoring of HR was done during the whole experiments. RESULTS: During the incremental exercises, SmO2 changed slightly within 100 watts (ΔSmO2: 8±11%, p>0.05). And SmO2 dropped down obviously when the exercise intensity exceeded 150 watts (ΔSmO2: 62±8%, p<0.05). After exercises, SmO2 would appear enhanced recovery (ΔSmO2: 65±13%, p<0.05). When the SmO2 turning point of sharp decrease abruptly appeared, the integrate EMG (iEMG) appeared sharp increase (ΔiEMG: 67±12μVs, p<0.05). The analyses showed that SmO2 was highly correlated with iEMG and HR. CONCLUSIONS: Higher exercise intensity in the muscle lead to lower SmO2. When stopping exercising, the oxygen demand suddenly falls, but the heart rate is still elevated and blood vessels dilated, and a rapid increase in SmO2 is observed. And we observed that SmO2, iEMG and HR have high correlation. Therefore, SmO2 may act as an important role in affecting EMG parameters of muscle performance and the internal environment of the body. [ABSTRACT FROM AUTHOR]

Denaturing gradient gel electrophoresis (DGGE) is a powerful technique to reveal the community structures and composition of microorganisms in complex natural environments and samples. However, positive and reproducible polymerase chain reaction (PCR) products, which are difficult to acquire for some specific samples due to low abundance of the target microorganisms, significantly impair the effective applications of DGGE. Thus, nested PCR is often introduced to generate positive PCR products from the complex samples, but one problem is also introduced: The total number of thermocycling in nested PCR is usually unacceptably high, which results in skewed community structures by generation of random or mismatched PCR products on the DGGE gel, and this was demonstrated in this study. Furthermore, nested PCR could not resolve the uneven representative issue with PCR products of complex samples with unequal richness of microbial population. In order to solve the two problems in nested PCR, the general protocol was modified and improved in this study. Firstly, a general PCR procedure was used to amplify the target genes with the PCR primers without any guanine cytosine (GC) clamp, and then, the resultant PCR products were purified and diluted to 0.01 μg ml. Subsequently, the diluted PCR products were utilized as templates to amplify again with the same PCR primers with the GC clamp for 17 cycles, and the products were finally subjected to DGGE analysis. We demonstrated that this is a much more reliable approach to obtain a high quality DGGE profile with high reproducibility. Thus, we recommend the adoption of this improved protocol in analyzing microorganisms of low abundance in complex samples when applying the DGGE fingerprinting technique to avoid biased results. [ABSTRACT FROM AUTHOR]

This paper investigates the robust delay-dependent stability problem for neutral system with mixed delays and nonlinear perturbations. A delay decomposition approach is used in this paper in which the information of the delayed plant states can be taken into full consideration. Then, based on a special Lyapunov functional approach, the novel delay-dependent stability criteria are obtained in terms of linear matrix inequalities (LMIs). A numerical example illustrates the effectiveness of the derived method and the improvement over some existing methods. [ABSTRACT FROM AUTHOR]

Abstract: In the present paper, glass forming ability (GFA) of Zr57Cu20Al10Ni8Ti5− x Ag x (x = 0, 1, 2, 3, 4, 5) bulk metallic glasses (BMGs) are studied using conventional copper mold suction casting method. The critical diameter of amorphous rod is improved from 8mm of Zr57Cu20Al10Ni8Ti5 to 20mm of Zr57Cu20Al10Ni8Ag5 by fully substituting Ti with Ag. The great improvement of GFA is attributed to the enlarged negative mixing enthalpy, large atomic packing fraction, and low critical cooling rate, which are −32.026kJ/mol, 0.761, and 2.5K/s, respectively. The mechanical property is also improved by substituting Ti with Ag. The yield strength, ultimate strength and plastic strain are enhanced from (1469MPa, 1490MPa and 0.1%) for Zr57Cu20Al10Ni8Ti5 BMG to (1612MPa, 1746MPa and 2.1%) for Zr57Cu20Al10Ni8Ag5 BMG, respectively. [Copyright &y& Elsevier]

Background: Bloodstream infections due to Candida species cause significant morbidity and mortality, and the epidemiology of Candida infection is changing. Surveillance for candidemia is necessary to detect trends in species distribution and antifungal resistance. Methods: The medical and electronic records of all patients who had candidemia at the authors' hospital from 2009 to 2011 were reviewed for demographic data and clinical information, including the infecting Candida species, resistance to antifungals and survival, and the presence of risk factors associated with candidemia. Results: A total of 133 distinct episodes of candidemia were identified over the study period. The annual incidence of candidemia ranged between 0.71 and 0.85 cases/1000 hospital discharges. The most frequent Candida species were C. tropicalis (28.6%), followed by C. albicans (23.3%) and C. parapsilosis (19.5%). The rates of susceptibility to antifungal agents were as followed: voriconazole (97.8%), itraconazole (69.5%), fluconazole (46.1%), ketoconazole (38.9%). Out of 131 evaluable patients, 34 (26.0%) died within 30 days from the onset of candidemia. C. tropicalis candidemia was associated with the highest mortality rate (44.7%). Regarding the crude mortality in the different units, patients in Hemato-Oncology ward had the highest mortality rate (66.7%), followed by patients in cardiovascular wards and ICU (57.1% and 25.6%, respectively). Predictors of 30-day mortality were identified by uni- and multivariate analyses. Complicated abdominal surgery, presence of central venous catheter (CVC), neutropenia, candidemia due to C. tropicalis and poor treatment with fluconazole were significantly associated with the 30-day mortality. Presence of CVC (odds ratio[OR] = 4.177; 95% confidence interval [CI] = 1.698 to 10.278; P = 0.002) was the only independent predictor for mortality in the multivariate analysis. Conclusion: This report provides baseline data for future epidemiological and susceptibility studies and for the mortality rates associated with candidemia in our hospital. The knowledge of the local epidemiological trends in Candida species isolated in blood cultures is important to guide therapeutic choices. [ABSTRACT FROM AUTHOR]

Background: The yeast Candida is one of the most frequent pathogens isolated from bloodstream infections and is associated with significant morbidity and mortality. Problems with clinical and microbiological diagnosis of invasive candidiasis (IC) have prompted the development of non-culture-based laboratory methods. Previous reports suggest that serological detection of antibodies might be useful for diagnosing systemic candidiasis. Methods: Diagnosis of IC using antibodies against recombinant Candida albicans enolase (Eno) and fructose-bisphosphate aldolase (Fba1) was evaluated. Using recombinant Eno and Fba1 as coating antigens, enzyme-linked immunosorbent assays (ELISAs) were used to analyze sera from patients with candidemia (n = 101), Candida colonization (n = 50), bacteremia (n = 84), invasive aspergillosis (n = 40); and from healthy controls (n = 200). Results: The results demonstrated that ELISA detection of anti-Eno and anti-Fba1 IgG distinguished IC from other pathogenic infections in patients and healthy individuals. The sensitivity, specificity, and positive and negative predictive values were 72.3%, 94.7%, 78.5% and 93% for anti-Eno, and 87.1%, 92.8%, 76.5% and 96.4% for anti-Fba1 antibodies, respectively. Combining these two tests improved sensitivity up to 90.1% and negative predictive value up to 97.1%, with specificity and positive predictive values of 90.6% and 72.2%. The tests were specific to the Candida genus and antibody titers were higher for candidemia patients than for controls. Positive antibody tests were obtained before blood culture results for 42.2% of patients for anti-Eno and 51.1% for anti-Fba1. Conclusion: These data suggest that tests that detect IgG antibodies against Candida enolase and fructose-bisphosphate aldolase, especially when used in combination, could be a powerful tool for diagnosing IC. [ABSTRACT FROM AUTHOR]

Abstract: As well known, internal friction (Q−1 ) is one of useful resorts for investigating the mechanical relaxation behaviors of bulk metallic glasses (BMGs). However, so far it has been controversial on ascertaining the authentic position of crystallization temperature (Tx ) when the peak arises on Q−1 -T heating curve of BMGs. Based on the isochronous measurement results of internal friction and resistivity (ρ) on a series of BMGs, a novel method for determining Tx of BMGs was proposed. By differentiating the curve of Q−1 -T with respect to temperature to obtain dQ−1/dT-T curve, the inflexion temperature at the left side of the Q−1-T peak can easily be determined. It is interesting to find that, for all the investigated BMGs in this paper, this inflexion temperature (the peak position of the dQ−1/dT-T curve) is in correspondence with the Tx obtained from ρ-T curve (ρ is very sensitive to crystallization), with the temperature error of ±1.5K. These results suggest that in studying the internal friction behaviors of BMGs, the crystallization temperature can be determined with the inflexion temperature of the Q−1-T curve, and the position of Tx for BMGs locates at the left side of the Q−1-T peak, rather than at the Q−1-T peak temperature or others as pointed in some references. [Copyright &y& Elsevier]

The current paper focuses on the solidification characteristics of a Cu-Sb eutectic alloy in its different liquid states. Liquid alloy resistivity-temperature patterns suggest an irreversible temperature-induced liquid-liquid structure transition (TI-LLST), and a reversible TI-LLST occurred during the heating-cooling runs. A set of solidification experiments was conducted based on the results. The irreversible TI-LLST caused an enhanced solidification undercooling, increased solidification rate, refined regular eutectic morphologies, and absence of a pre-eutectic Cu2Sb phase. The reversible TI-LLST resulted in different phase compositions and eutectic structures. The mechanisms behind these transitions are also briefly discussed. [ABSTRACT FROM AUTHOR]

Local acidosis has been found in various pain-generating conditions such as inflammation and tissue injury. Cannabinoids exert a powerful inhibitory control over pain initiation via peripheral cognate receptors. However, the peripheral molecular targets responsible for the antinociceptive effects of cannabinoids are still poorly understood. Here, we have found that WIN55,212-2, a cannabinoid receptor agonist, inhibits the activity of native acid-sensing ion channels (ASICs) in rat dorsal root ganglion (DRG) neurons. WIN55,212-2 dose-dependently inhibited proton-gated currents mediated by ASICs. WIN55,212-2 shifted the proton concentration-response curve downwards, with an decrease of 48.6±3.7% in the maximum current response but with no significant change in the EC50 value. The inhibition of proton-gated current induced by WIN55,212-2 was almost completely blocked by the selective CB1 receptor antagonist AM 281, but not by the CB2 receptor antagonist AM630. Pretreatment of forskolin, an AC activator, and the addition of cAMP also reversed the inhibition of WIN55,212-2. Moreover, WIN55,212-2 altered acid-evoked excitability of rat DRG neurons and decreased the number of action potentials induced by acid stimuli. Finally, WIN55,212-2 attenuated nociceptive responses to injection of acetic acid in rats. These results suggest that WIN55,212-2 inhibits the activity of ASICs via CB1 receptor and cAMP dependent pathway in rat primary sensory neurons. Thus, cannabinoids can exert their analgesic action by interaction with ASICs in the primary afferent neurons, which was novel analgesic mechanism of cannabinoids. [ABSTRACT FROM AUTHOR]

Abstract: Background: Invasive aspergillosis (IA) is an important cause of mortality in critically ill patients, but the diagnosis is difficult as clinical and radiological signs are neither sensitive nor specific. Serum galactomannan (GM) is a useful marker for IA, but exhibits low sensitivity in non-neutropenic patients. In our previous work, strong antibody reactivity to thioredoxin reductase of Aspergillus fumigatus was found in non-neutropenic IA patients. Methods and results: Using recombinant thioredoxin reductase GliT (TR), an antigenic protein secreted by A. fumigatus, as the coating antigen, an enzyme-linked immunosorbent assay (ELISA) for detecting anti-TR antibodies was developed. The antibody response to TR in IA animal models and 42 non-neutropenic patients with culture- and/or histology-documented IA was investigated. The results showed that anti-TR antibody was detectable in rabbit serum 7–9days after exposure to the fungus. The sensitivity and specificity of the anti-TR antibody assay in patients were 80.9% and 96%, respectively, while the sensitivity of GM in this group of patients was only 52.3%. The specificity of the assay was confirmed by testing the sera from patients infected with other pathogenic fungal species and bacteria. [Copyright &y& Elsevier]

To study Pb–Te melt structural evolution, its electrical resistivity was experimentally investigated using the DC four-probe method during heating and cooling processes. An abnormal resistivity change was detected in some compositions of the Pb–Te melt, but not in Pb, Te, Pb–Te eutectic and Pb–Te 90 wt% melts. Since resistivity is a structure-sensitive physical quantity and resistivity resort was verified valid for investigating liquid structural changes in past studies, the abnormal resistivity variation can reflect some melt structure characters. So it can be inferred that in some compositions of Pb–Te melts, a temperature-induced liquid structure transition occurred and some compositions did not exhibit the phenomenon. Besides these, some analyses from the perspective of the nearly free electron model are also given in this article. [ABSTRACT FROM PUBLISHER]

This paper is one of a series of country case studies reviewing nations' regulatory body for the healthcare industry. It reports Israel's modern regulatory environment and the social background that has shaped its unique agency structure and functionalities. With the Ministry of Health acting as a combination regulatory body, international trade negotiator, and industry supporter, Israel has established a complex partnership relation between government and industry without compromising the regulatory functions of the agency. The result is a focus on protecting Israeli citizen's health and safety; expanding exports; and assuring the quality of pharmaceutical imports. [ABSTRACT FROM AUTHOR]

To study the melt structural evolution, at different temperatures, electrical resistivity evolution patterns with the time of Sn-Sb10 melt were experimentally investigated during isothermal processes. There was no change in resistivity during the isothermal process at 850°C for 360 min, while at higher temperatures, i.e. 875°C, 885°C, and 900°C, there was a dropping turn in the resistivity-time curves at different ranges. The higher the isothermal temperature, the earlier the dropping turn and the shorter the time range. As the resistivity resort was verified to be sensitive and valid for investigating liquid structure changes in past studies, the resistivity turn suggests the occurrence of a temperature-induced liquid structure transition. Based on the results, the kinetic mechanism of the liquid transition was also studied and the activation energies of the transition were calculated too. [ABSTRACT FROM AUTHOR]

Bilateral dichotomous data are very common in modern medical comparative studies (e.g. comparison of two treatments in ophthalmologic, orthopaedic and otolaryngologic studies) in which information involving paired organs (e.g. eyes, ears and hips) is available from each subject. In this article, we study various confidence interval estimators for proportion difference based on Wald-type statistics, Fieller theorem, likelihood ratio statistic, score statistics and bootstrap resampling method under the dependence or/and independence models for bilateral binary data. Performance is evaluated with respect to the coverage probability and expected width via simulation studies. Our empirical results show that (1) ignoring the dependence feature of bilateral data could lead to severely incorrect coverage probabilities; and (2) Wald-type, score-type and bootstrap confidence intervals based on the dependence model perform satisfactorily for small to large sample sizes in the sense that their empirical coverage probabilities are close to the pre-specified nominal confidence level and are hence recommended. A real data from an otolaryngologic study is used to illustrate the proposed methods. [ABSTRACT FROM AUTHOR]

Background: As the expression of human sperm protein 17 (Sp17) in normal tissue is limited and the function is obscure, its aberrant expression in malignant tumors makes it to be a candidated molecular marker for tumor imaging diagnosis and targeting therapy of the diseases.The aim of this research is to evaluate the targeting effects of anti-sperm protein 17 monoclonal antibody (anti-Sp17) on cancer in vivo and investigate its usefulness as a reagent for molecular imaging diagnosis. Methods: Immunohistochemistry was used to identify the expression of Sp17 in a hepatocellular carcinoma cell line and tumor xenograft specimens. A near infrared fluorescence dye, ICG-Der-02, was covalently linked to anti- Sp17 for in vivo imaging. The immuno-activity of the anti-Sp17-ICG-Der-02 complex was tested in vitro by ELISA; it was then injected into tumor-bearing nude mice through the caudal vein to evaluate its tumor targeting effect by near infrared imaging system. Results: Overexpression of Sp17 on the surface of the hepatocellular carcinoma cell line SMMC-7721 was demonstrated. Anti-Sp17-ICG-Der-02 with immuno-activity was successfully synthesized. The immuno-activity and photo stability of anti-Sp17- ICG-Der-02 showed good targeting capability for Sp17 expressing tumor models (SMMC-7721) in vivo, and its accumulation in the tumor lasted for at least 7 days. Conclusions: Anti-Sp17 antibody targeted and accumulated in Sp17 positive tumors in vivo, which demonstrated its capability of serving as a diagnostic reagent. [ABSTRACT FROM AUTHOR]

By means of DC four-probe technique, the temperature dependence of the electrical resistivity (ρ-T) of liquid Bi-10wt%Te alloy has been measured. Two abnormal changes on the ρ-T curve within the temperature ranges of 497-550°C and 639-708°C suggested that two irreversible liquid-liquid structural changes (LLSC) occurred. To explore the effects of the LLSC on the solidification behaviour of the alloy, solidification experiments were carried out. The results show that after experiencing LLSC, there will be enlarged undercooling, much finer microstructures and larger quality of Bi2Te phase. Moreover, the morphology of solidified Bi2Te is changed from dendrite to equiaxed. [ABSTRACT FROM AUTHOR]

In a context of intensified globalisation, knowledge diaspora as "trans-national human capital" have become increasingly valuable to society. With an awareness of a need for more empirical studies especially in Australia, this article concentrates on a group of academics who were working at a major university in Australia and came originally from the Chinese mainland. The study explores their life, work and international research collaborations, using a case study approach with semi-structured interviews as the data collection method. The study found that while globalisation shapes the work and the contributions to Australia, by academics from China, they exert their initiatives to respond to and further reshape globalisation. Equipped with their Chinese cultural and educational backgrounds, academic experience in the West, and active membership in the international knowledge system, the Chinese knowledge diaspora are a modern kind of cosmopolitan literati. They are aware of the impact of globalisation and contribute actively to higher education internationalisation in both Australia and China, have maintained their cultural identity and made good use of their Chinese educational background. Their international collaborations, however, are more likely to be with the scholars from Western countries due to some difficulties they have experienced in China and Australia, and to the current setup of the global knowledge system. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, Bi-60wt.%Te and Bi-80wt.%Te alloys are selected for experiments to explore the effects of temperature-induced discontinuous liquid–liquid structure transitions TI-LLST on the solidification behaviors and solidified microstructures. Anomalous changes of electrical resistivity of the liquid Bi-60wt.%Te and Bi-80wt.%Te alloys with temperature suggested that TI-LLST occurred within 798–828 and 745–779°C. The solidification results show that solidification behaviors and solidified microstructures of Bi–Te alloys will be apparently distinct when the melt is prepared above the critical temperature. It is found that the nucleation undercooling is larger when the melt experienced the TI-LLST, which leads to finer solidification microstructures. [Copyright &y& Elsevier]

Background: Sperm protein 17 (Sp17) is a highly conserved mammalian protein in the testis and spermatozoa and has been characterized as a tumor-associated antigen in a variety of human malignancies. Many studies have examined the role of Sp17 in tumorigenesis and the migration of malignant cells. It has been proposed as a useful target for tumor-vaccine strategies and a novel marker to define tumor subsets and predict drug response. This study aimed to investigate the expression of Sp17 in endometrial and cervical cancer specimens, its possible correlation with the pathological characteristics, and its value in the diagnosis and immunotherapy of the related cancers. Methods: The monoclonal antibodies against human Sp17 were produced as reagents for the analysis and immunohistochemistry was used to study two major kinds of paraffin-embedded gynecological cancer specimens, including 50 cases of endometrial cancer (44 adenous and 6 adenosquamous) and 31 cases of cervical cancer (15 adenous and 16 squamous). Normal peripheral endometrial and cervical tissues were used as controls. Results: Sp17 was found in 66% (33/50) of the patients with endometrial cancer and 61% (19/31) of those with cervical cancer. Its expression was found in a heterogeneous pattern in the cancer tissues. The expression was not correlated with the histological subtype and grade of malignancy, but the staining patterns were different in endometrial and cervical cancers. The hyperplastic glands were positive for Sp17 in the normal peripheral endometrial and cervical tissues in 10% (8/81) of the patients. Conclusions: Sp17 is highly expressed in human endometrial and cervical cancers in a heterogeneous pattern. Although the expression frequency of Sp17 is not correlated with the histological subtype, the staining pattern may help to define endometrial and cervical cancers. Sp17 targeted immunotherapy of tumors needs more accurate validation. [ABSTRACT FROM AUTHOR]

We find the greatest value α and least value β such that the double inequality αA(a, b) + (1 − α)H(a, b) < P(a, b) < βA(a, b) (1−β)H(a, b) holds for all a, b > 0with a/ b. Here A(a, b),H(a, b), and P(a, b) denote the arithmetic, harmonic, and Seiffert’s means of two positive numbers a and b, respectively. [ABSTRACT FROM AUTHOR]

This paper studies delay-dependent asymptotical stability problems for the neural system with time-varying delay. By dividing the whole interval into multiple segments such that each segment has a different Lyapunov matrix, some improved delay-dependent stability conditions are derived by employing an integral equality technique. A numerical example is given to demonstrate the effectiveness and less conservativeness of the proposed methods. [ABSTRACT FROM AUTHOR]

This article studies a class of Cohen-Grossberg neural networks (CGNNs) with variable and distributed delays. Some novel conditions guaranteeing the existence, uniqueness and the estimated location of the equilibrium points are obtained. Using these results, the global asymptotic stability of the CGNNs can be derived without demanding the boundedness and the globally Lipschitz condition of the activation functions. Two numerical examples are demonstrated to verify the theoretical results. [ABSTRACT FROM AUTHOR]

Based on the aromatic dicarboxylic acid and N-donor ligands with different conformations, four Zn(II) metal–organic frameworks, namely [Zn(mfda)(L1)] (1), [Zn2(mfda)2(L2)]·DMF·H2O (2), [Zn2(mfda)2(L3)(H2O)]·DMF (3) and [Zn2(mfda)2(L4)] (4) have been synthesized (mfda = 9,9- dimethylfluorene-2,7-dicarboxylate anion, L1= 1,10-phenanthroline, L2= 4,4′-bipyridine, L3= 2,5-bis(4-pyridyl)-1,3,4-ocadiazole and L4= 1,4-bis(imidazol-1-ylmethyl)benzene). Single-crystal X-ray diffraction has revealed that all compounds exhibit entangled structures. Compound 1is composed of 1D zigzag chains that are entangled through the π–π stacking interactions to generate a three-fold interpenetrating diamond-like networks. 2exhibits a two-fold interpenetrating (α-Po) net, which leaves 1D channels with high free volume. In 3, parallel mutual polythreadings of 2D layers are connected by hydrogen bonds into a self-penetrating framework with (44·610·7)(4·5·6)(46·52·616·73·9) topology. For 4, the interpenetrating 2D layers are connected into a self-interpenetrating net with (49·66) topology. The potential of N-donor ligands to produce interesting metal–organic frameworks is investigated. Luminescent studies show that 1–4exhibit strong blue fluorescent emissions. [ABSTRACT FROM AUTHOR]

Abstract: In a distributed system, broadcasting is an efficient way to dispense data in certain highly dynamic environments. While there are several well-known on-line broadcast scheduling strategies that minimize wait time, there has been little research that considers on-demand broadcasting with timing constraints. One application which could benefit from a strategy for on-demand broadcast with timing constraints is a real-time database system. Scheduling strategies are needed in real-time databases that identify which data item to broadcast next in order to minimize missed deadlines. The scheduling decisions required in a real-time broadcast system allow the system to be modeled as a Markov Decision Process (MDP). In this paper, we analyze the MDP model and determine that finding an optimal solution is a hard problem in PSPACE. We propose a scheduling approach, called Aggregated Critical Requests (ACR), which is based on the MDP formulation and present two algorithms based on this approach. ACR is designed for timely delivery of data to clients in order to maximize the reward by minimizing the deadlines missed. Results from trace-driven experiments indicate the ACR approach provides a flexible strategy that can outperform existing strategies under a variety of factors. [Copyright &y& Elsevier]

The temperature dependences of structure and some physical properties of eutectic InSn49.1 (wt%) melt were investigated by means of high temperature X-ray diffractometer, internal friction and DC four-probe method. In the heating procedure of the melt, a discontinuous temperature induced liquid-liquid structure change was observed within the temperature range of 620-850°C. The X-ray diffraction results show that both mean nearest neighbour distance and coordination number altered anomalously within 650-800°C; in addition, the size of the ordering domain and ordering degree of the melt all decreased evidently at the end of the structure change. It is presumed that this structure change resulted from the adjustment of the atomic bonds of Sn-Sn and In-In. A theoretical discussion on the correlation between structure and physical properties of InSn49.1 melt was also given. [ABSTRACT FROM AUTHOR]

In recent years, a number of studies with different methods dedicated to structures and properties of liquid alloys revealed the occurrence of temperature-induced liquid–liquid structural transformation (TI-LLST). As yet, however, few investigations have concerned the reversibility of TI-LLST. The present paper reports a reversible TI-LLST in Pb–Sn alloys, which was observed with the electrical resistivity method during succeeding cooling and heating runs after the first heating process. The reversible TI-LLST is not the same as the TI-LLST in the first heating run, because the temperature ranges and the patterns are different from those of the latter. It is interesting that the similar phenomenon is also observed in pure tin, which suggests that the reversible TI-LLST in liquid Pb–Sn alloy is related to that in liquid Sn. [ABSTRACT FROM AUTHOR]

In this article, we investigate the kinetics of temperature-induced liquid-liquid structure changes in In-Sn80 wt% and In-Pb80 wt% alloy melts by measuring the electrical resistivity, and obvious kinetic phenomena are observed during isothermal and heating experiments. We found that the time evolution of the electrical resistivity could be described by the autocatalytic reaction model, which is an indication of nucleation growth type. The mechanism of autocatalysis and the kinetic phenomena have been roughly discussed. Using Kissinger's equation, their apparent activation energy (Ek) at transition beginning point has also been calculated. [ABSTRACT FROM AUTHOR]

The electrical resistivities of liquid Bi, Sb, and some of their alloys Pb-Bi, Pb-Sb have been investigated as a function of temperature, and the effect of heating-rate on the turning points of liquid Bi has also been investigated. Obvious and interesting hump phenomena are observed on resistivity-temperature curves of liquid Bi, Sb, and Pb-Bi, Pb-Sb alloys on heating at the temperature far above their liquidus. Moreover, the transition temperature of liquid Bi increases with heating-rate increasing, which shows that this kind of transition is in accordance with kinetic characteristics. However, comparing the heating curve with the cooling one, we found that the anomalous hump phenomenon is irreversible in liquid Bi, Sb, and Pb-Bi, Pb-Sb alloys. [ABSTRACT FROM AUTHOR]

Abstract: A fast, accurate, sensitive, selective and reliable method using reversed-phase high-performance liquid chromatography–mass spectrometry coupling with an electrospray ionization interface was developed and validated for the determination of finasteride in human plasma. After deprotienation with acetonitrile, centrifugation, evaporation to dryness and dissolving in mobile phase, satisfactory separation was achieved on a Hypersil-Keystone C18 reversed-phase column using a mobile phase consisting of acetonitrile–water (46:54, v/v), 0.1% acetic acid and 0.1% trifluoracetic acid. Carbamazepine (IS) was used as internal standard. This method involved the use of the [M +H]+ ions of finasteride and IS at m/z 373 and 237 with the selective ion monitoring (SIM) mode. The calibration curve was linear in the range of 0.2–120ngml−1. The limit of quantification for finasteride in plasma was 0.2ngml−1 with good accuracy and precision. The intra-assay precision and accuracy were in the range of 2.1–11.2% and −1.3% to 8.5%, respectively. The inter-assay precision and accuracy were in the order of 3.4–12.1% and −1.5% to 11.5%, respectively. The mean sample extract recoveries of the method were higher than 85% and 74% for finasteride and internal standard (IS), respectively. The assay has been successfully used to estimate the pharmacokinetics of finasteride after oral administration of a 5mg tablet of finasteride to 24 healthy volunteers. [Copyright &y& Elsevier]

Through the theoretical study of concentration-dependent thermodynamic and microscopic functions in some reports, chemical short-range orders (CSROs) have been proved to persist in Cu–Sn melts. However, it is not clear insofar in which concentration and temperature ranges do these CSROs exist in melts, and how they change with temperature. This study investigates the liquid structure with temperature of Cu–Sn alloys by electrical resistivity and DSC. The results show that some CSROs inheriting solid structures bring abnormal transition of resistivity at a temperature hundreds of degrees above the liquidus for all the studied Cu–Sn melt. Especially for the melts with 50 to 70% Cu, there also exist ‘associates’ of unlike atoms, which reduce continuously with increasing temperature after melting and result in negative temperature coefficients of resistivities (TCRs). In the figures of DSC-temperature, some endothermic peaks consistent with the temperatures of resistivity transitions verify these abnormal transitions of liquid structure. [ABSTRACT FROM AUTHOR]

Abstract: The relationship between the total relaxation time at the glass transition and Glass Forming Ability (GFA) of Bulk Metallic Glasses (BMG) has been discussed. Subsequently is applied to estimate the GFA of Zr52.5Al10Ni14.6Cu17.9Ti5 and Zr57Al10Ni12.6Cu15.4Nb5 BMGs. The result indicates that the GFA of the former is greater than that of the latter, which is also demonstrated by the widely accepted criteria of both supercooled liquid region ΔT x and reduced glass transition temperature T rg. That testifies the relaxation time of glass transition () is feasible for depicting GFA of BMGs. As a criterion estimating GFA, could be easily obtained in practice, and then the occurrence of this criterion will promote exploring new bulk glassy composition. In addition, when and ΔT x are calculated, the characteristic temperatures are determined by a electrical resistivity method besides DSC method. The values obtained from electrical resistivity method agree well with those from DSC method, which proves that the electrical resistivity method is applicable for determining the characteristic temperatures of BMGs. [Copyright &y& Elsevier]

Abstract: Atractylodes macrocephala (baizhu) and Atractylodes lancea (cangzhu), which are two famous Atractylodes medicinal plants, have traditionally been used as important ingredient of several Chinese herbal medicines. The volatile constituents are the main active components in them. To avoid the traditional and time-consuming hydrodistillation, the analyses of volatile components in baizhu and cangzhu were carried out by means of headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography–mass spectrometry (GC–MS). The headspace volatiles were collected using a polydimethylsiloxane–divinylbenzene (PDMS–DVB, 65μm) fiber. The extraction conditions including extraction temperature, equilibrium time, extraction time and desorption time were optimized using the total peak areas as index. The best response was obtained when the extraction temperature, equilibrium time, extraction time and desorption time were 70°C, 30, 30 and 4min, respectively. Thirty-six components representing 90.72% of the total peak areas of baizhu were identified. The highest content component of the HS-SPME sample of baizhu was atractylone (40.12%). For cangzhu, 56 components representing 90.38% of the total peak areas of cangzhu were identified and the highest content component of the HS-SPME sample of cangzhu was eudesma-4(14),11-diene (16.49%). This study showed that baizhu and cangzhu have 23 common components. The result suggested the developed method could be used to compare the similarities and differences between the above-mentioned two Chinese herbs. [Copyright &y& Elsevier]

Abstract: The electrical resistivity of liquid Sn–Bi alloys has been investigated as a function of temperature by the DC four-probe technique. Obvious turning point is observed on resistivity–temperature () curve of different Sn–Bi alloy, while the resistivity increases linearly with temperature increasing before the turning point. Moreover, different composition alloy shows different turning temperature on curve. Since resistivity is one of the physical properties sensitive to structure, its discontinuous alteration with temperature reveals the liquid–liquid structure transition in the Sn–Bi melts. Furthermore, comparing the heating curve with the cooling one of the eutectic alloy Sn43Bi57, it is found that the possible structure transition is irreversible. [Copyright &y& Elsevier]

The electrical resistivities of liquid Bi–Sb alloys have been measured by DC four-probe method within Bi-rich composition through a wide temperature range. The distinct anomaly of a hump shape was observed on resistivity–temperature (ρndash; T ) curves for liquid Bi–Sb alloys on heating at the relatively high temperatures. These anomalies have revealed the temperature-induced liquid–liquid phase transition in Bi–Sb melts. The DSC results for BiSb20wt% alloy further prove the existence of liquid–liquid transition. Measuring the ρ– T curves first on heating and then on cooling we have found that on cooling the ρ– T curve remained linear. It means that the postulated liquid–liquid transition may be irreversible. [ABSTRACT FROM AUTHOR]

Abstract: Cordyceps sinensis (Cs) is a well-known traditional Chinese medicine (TCM) and Cordyceps mycelia (Cm), a cultured Cordyceps, is a substitute for Cordyceps sinensis. The most important active components in them are nucleosides. A high selective, sensitive and accurate high performance liquid chromatography method with photodiode array detection (DAD) and mass spectrometric detection has been developed for simultaneous separation, identification and quantification of nucleosides in Cs and Cm using a mobile phase including (A) ammonium acetate (40mM, pH 5.2) and (B) methanol with a gradient system on a 2.0mm×150mm Shimadzu VP-ODS column. The presence of each nucleoside in Cs and Cm was ascertained by comparison of MS data, UV spectra and retention time with standards. LC/ESI-MS in selective ion monitoring (SIM) mode were used for the quantification of nucleosides in Cs and Cm. 2-Chloroadenosine was used as internal standard for this assay. The precisions and accuracies were in the range of 1.5–5.3% and −3.5 to 5.0%, respectively. The limits of detection and quantification for nucleosides were in the order of 0.1–0.6μgml−1 and 0.5–2.0μgml−1, respectively. The recoveries were in the range of 92.0–107.0%. With the developed method, the concentrations of nucleosides in Cs and Cm from different sources were determined. Cs, characterized with far lower concentration of adenosine and cordycepin than Cm, can be very easy to distinguish from Cm. This reliable method would be useful for the study and quality control of Cordyceps sinensis and its substitutes. [Copyright &y& Elsevier]

Different from the conventional liquid theory, experimental evidence suggests that there might be discontinuous liquid-liquid (L-L) structure transitions for some alloys. By the resistivity experiments, it is assumed that a temperature-induced L-L structure transition might occur in liquid lead-bismuth (PbBi) alloy. The electrical resistivity of four compositions for PbBi alloy versus temperature was precisely measured in our experiment. It was found that the resistivity increases linearly with temperature rising in a certain range of temperature above the melting point. During subsequent calefaction, the results obviously showed that a turning point appears in the resistivity-temperature (R-T) curve for every composition at a certain temperature. The turning temperature depends on composition. It can be considered that there is L-L structure transition in some regions of high temperature for PbBi alloy. [ABSTRACT FROM AUTHOR]

Abstract: The patterns of electrical resistivity of lead–tin (Pb–Sn) alloys with different compositions, along with pure liquid lead and tin, have been investigated as a function of temperature, using the DC four-probe technique. Evident turning points are observed on resistivity–temperature curves of the four liquid Pb–Sn alloys, and the resistivities increase linearly with rising temperature before the turning points. Moreover, the turning points are all at the temperature scope far above the liquidus. In case of both liquids pure lead and tin, however, the resistivity–temperature curves are linear within the measured temperature. Since resistivity is one of the physical properties sensitive to structures, it is suggested that there are temperature-induced structure changes in the liquid Pb–Sn alloys. [Copyright &y& Elsevier]