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On the basis of Grubbs’ method and linear regression to exclude abnormal values, a novel experimental design and corresponding procedures as well as a theoretical strategy on data processing were investigated in an attempt to improve the evaluation accuracy of the cooling effects of road coatings. Five types of new cooling coatings were developed according to the requirements of current asphalt pavements and the optimal regression variables for cooling effects were selected. The results showed that the coefficients of regression formulas for the cooling effect of the different cooling coatings were around 0·99, suggesting that there was a significant correlation among the fitting variables. In particular, if the temperature of the asphalt pavement was 60°C, the cooling effect of the new coatings reached a value of nearly ten per cent, indicating that the developed data processing method could solve the inaccuracy problem of experimental data caused by different environmental factors.

We introduce and adopt the concept of a phenomenological parameter, microstructure entropy, S*, to understand the yield strength in alloy systems with bimodal grain size distribution obtained from large sets of experimental data. 60 groups of bimodal grain size distribution data was obtained through the application of an ingenious concept involving severe cold deformation to obtain dislocation cell-type of martensite, followed by annealing when martensite reverts to austenite by shear or diffusion mechanism, with the aim to obtain ultrafine grain size. Six factors emerged from statistical data analysis through EBSD studies in terms of grain size and grain numbers from 60 sets of data. Microstructure entropy (S*) was obtained from the bimodal structure data in a self-similar regime. Inverse of the square root of microstructure entropy ( 1 S * ) and yield strength exhibited a linear relationship. The proposed conceptual methodology has wide acceptance for any grain size distribution to obtain microstructure entropy (S*) of a specific grain structure and predict yield strength. A generic equation similar to Hall-Petch relationship, but involving microstructure entropy is proposed to predict and understand yield strength of metallic systems characterized by grain size distribution or microstructural evolution.

Subclinical hypothyroidism (SCH) has been shown to be associated with microbiota. However, the association between SCH and oral microbiota has not yet been elucidated. The results of our previous clinical studies showed that Prevotella intermedia was abundant in the oral microbiota of SCH patients. This study aimed to investigate the relationship between SCH and oral microbiota, verify the pathogenicity of P. intermedia in SCH, and preliminarily explore the possible mechanism. The SCH mouse model with oral application of P. intermedia was established, and the variance in the mouse oral microbiota and changes in thyroid function and metabolism were detected in mice. Student’s t test and analysis of variance were used for statistical analysis. Oral application of P. intermedia changed the composition of the oral microbiota of SCH mice, which enhanced the damage to the thyroid and decreased the expression of functional genes of the thyroid. Moreover, P. intermedia decreased oxygen consumption and aggravated glucose and lipid metabolism disorders in SCH mice. Glucose tolerance and insulin tolerance decreased, and the triglyceride content of the liver and inflammatory infiltration in adipose tissue increased in SCH mice after P. intermedia stimulation. Mechanistically, P. intermedia increased the proportion of CD4+ T cells in cervical lymph nodes and thyroids in SCH mice. Th1 cells were suggested to play an important role in the pathogenesis of SCH involving P. intermedia. In conclusion, P. intermedia aggravated SCH manifestations, including thyroid dysfunction and glucose and lipid metabolism disorders, by causing immune imbalance in mice. This study sheds new light on the pathogenesis of SCH from the perspective of oral microbiota.

The Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) are low costing and noninvasive neuropsychological tests in screening Mild Cognitive Impairment (MCI) due to Alzheimer's disease (AD). There is no consensus on which test performs better in detecting MCI due to AD based on the different imperfect reference standards. Therefore, we conducted a meta-analysis to assess the diagnostic performance of MMSE and MoCA for screening MCI due to AD in the absence of a gold standard.Six electronic databases were searched for relevant studies until April, 2022. A hierarchical Bayesian latent class model was used to estimate the pooled sensitivity and specificity of MoCA and MMSE in the absence of a gold standard.90 eligible studies covering 21273 individuals for MMSE, 26631 individuals for MoCA were included in this meta-analysis. The pooled sensitivity was 0.71(95%CI: 0.67-0.74) for MMSE and 0.85(95%CI: 0.83-0.88) for MoCA, while the pooled specificity was 0.71(95%CI: 0.68-0.74) for MMSE and 0.79(95%CI: 0.76-0.81) for MoCA. MoCA was useful to "rule in" and "rule out" the diagnosis of MCI due to AD with higher positive likelihood ratio (4.07; 95%CI: 3.60-4.62) and lower negative likelihood ratio (0.18; 95%CI: 0.16-0.22). Moreover, the diagnostic odds ratio of MoCA was 22.08(95%CI: 17.24-28.29), which showed significantly favorable diagnostic performance.It suggests that MoCA has greater diagnostic performance than MMSE for differentiating MCI due to AD when the gold standard is absent. However, these results should be taken with caution given the heterogeneity observed.

Summary Accurate near-surface velocity structure is the key to improve the precision of statics and seismic imaging. We propose a novel method for complex near-surface velocity modeling based on a modified U-net from pre-stack seismic data. The method makes use of waveform information rather than travel time only. We design a number of complex near-surface velocity models and simulate shot gathers using the finite difference scheme. During the forward stage, the network develops a nonlinear relationship between the multi-shot seismic data and the corresponding velocity models. During the inversion stage, the trained network can be used to predict velocity models from the new shot gathers in a few minutes. Supported by numerical experiments on synthetic models, this method achieve a promising performance in complex near-surface velocity inversion.

Summary The effect of absorption attenuation on seismic wave is shown in amplitude attenuation and phase dispersion, which greatly reduces the resolution of the seismic profile. Attenuation compensation method is commonly used to eliminate these effects. Lots of researches about attenuation compensation have been carried out for many years. However, traditional attenuation compensation methods are usually not stable and have poor noise resistance. With the explosion of deep learning (DL), it is an inevitable trend to apply deep learning method to attenuation compensation. In this abstract, we first analyse the suitable network structure for the attenuation compensation problem, and we improve the structure of U-Net to make it suitable for processing single seismic trace, then we implement the attenuation compensation based on U-Net and Gabor transform, the comparison of the results shows that the compensation based on U-Net has better stability and noise resistance performance while effectively compensating the amplitude energy attenuation and the phase distortion.

Summary Post-stack acoustic impedance inversion has definitive geophysical significance.Traditional acoustic impedance inversion is based on convolutional model and requires low frequency model. When the definition of the initial model is not accurate, the impedance inversion is not credible. In addition, due to the filtering effect of seismic response, impedance inversion is band-limited.In this abstract, a method combining deep learning and transfer learning is used to inverse acoustic impedance. Independent of the initial model, the nonlinear relationship between seismic data and acoustic impedance can be established by CRNN. The network architecture trained by simulated data is finetuned with little logging data. Transfer learning not only overcomes the problem of less label data in field inversion, but also solves the approximation problem of convolutional model. We used two typical models with different geological characteristics to prove the effectiveness of the inversion method. This provides a new method for seismic inversion in field area.

Soil salinity is one of the major abiotic stresses negatively affecting plant growth and development. Global constraints on fresh water supplies and urban population growth have intensified the interest of using alternative water sources such as treated municipal wastewater for irrigating landscapes. In addition, nursery and greenhouse industry are pressured to recycle and reuse nutrient solution and runoff. All these alternative waters contain relatively high levels of salts, which could cause salt damage on sensitive plant species. Although quantitative information on crop salt tolerance exists for many agronomic crops, limited information is available for horticultural crops. Roses (Rosa spp.) are the most economically important and popular ornamental crops used for gardens and public and private landscapes and for cut flowers in the world. Rose has been traditionally categorized as a salt-sensitive species. However, recent research on salt tolerance of various cultivars of garden roses and greenhouse cut roses has shown that variations in salt tolerance exist among rose cultivars and there are moderately salt-tolerant rose cultivars and rootstocks. In this paper, studies on salt tolerance of garden roses and greenhouse cut roses were reviewed with emphasis on whole plant responses to salt stress and mineral nutrition. Molecular responses to salt stress are beyond this review.

In this study, an interactive two-stage fuzzy stochastic programming (ITFSP) method is developed for supporting crop planning and water resource allocation under uncertainty. ITFSP can effectively address uncertainties expressed as probability distributions and fuzzy-boundary intervals. It can also be utilized for in-depth analyzing different policy scenarios that are integrated with various economic implications since penalties are executed with recourse actions. ITFSP enables decision makers to identify a tradeoff between higher objective values and feasibility of constraints. The ITFSP method is applied to a real case of Hetao irrigation district, one of the largest irrigation districts for food production in China. Different scenarios for crop planning targets which reflect the attitudes of local authority to the available water resources are examined. Results discover that different scenarios lead to changed irrigation patterns, water shortages, penalties, as well as system benefits. Results also reveal that decision makers would be more positive to water allocation to crops of wheat and oil than maize; oil crop always possesses the priority of water allocation and would be partly satisfied even under the low flow. Solutions are useful for determining optimized cropland use and water allocation patterns in such an agricultural system in the arid region, which could hedge appropriately against future available water levels in more profitable and sustainable ways.

Summary Objective To explore the effect of vitamin D on turnover of articular cartilage with ovariectomy (OVX) induced OA, and to investigate transforming growth factor-β1 (TGF-β1) as a possible underlying mechanism mediated by 1α,25(OH) 2 D 3. Design Sixty-six rats were randomly allocated into seven groups: sham plus control diet (SHAM+CTL), OVX+CTL diet, sham plus vitamin D-deficient (VDD) diet, OVX+VDD diet, and three groups of ovariectomized rats treated with different doses of 1α,25(OH) 2 D 3 . The cartilage erosion and the levels of serum 17β-estradiol, 1α,25(OH) 2 D 3 and C-telopeptide of type II collagen (CTX-II) were measured. TGF-β1, type II Collagen (CII), matrix metalloproteinases (MMP)-9,-13 in articular cartilage were assessed by immunohistochemistry. TGF-β1 and CTX-II expression were measured in articular cartilage chondrocytes treated with/without tumor necrosis factor (TNF-α), 1α,25(OH) 2 D 3 , and TGF-β receptor inhibitor (SB505124) in vitro . Results Cartilage erosion due to OVX was significantly reduced in a dose-dependent manner by 1α,25(OH) 2 D 3 supplementation, and exacerbated by VDD. The expressions of TGF-β1 and CII in articular cartilage were suppressed by OVX and VDD, and rescued by 1α,25(OH) 2 D 3 supplementation. The expression of MMP-9,-13 in articular cartilage increased with OVX and VDD, and decreased with 1α,25(OH) 2 D 3 supplementation. In vitro experiments showed that 1α,25(OH) 2 D 3 increased the TGF-β1 expression of TNF-α stimulated chondrocytes in a dose-dependent manner. 1α,25(OH) 2 D 3 significantly counteracted the increased CTX-II release due to TNF-α stimulation, and this effect was significantly suppressed by SB505124. Conclusion VDD aggravated cartilage erosion, and 1α,25(OH) 2 D 3 supplementation showed protective effects in OVX-induced OA partly through the TGF-β1 pathway.

Making use of the steam heat storage in thermal generators enables them to operate in a "fast mode" to ramp up or down faster than regular, so as to better catch up with the fluctuations of wind power to improve system wind utilization. In such fast mode, generators have output dependent ramp rates and, distinguished from regular units, output and ramp rate dependent coal consumption costs. These fast generators cannot be properly described by using existing economic dispatch models, where generators usually have output dependent cost functions and constant ramp rate limits. This paper presents a new formulation and solution methodology of dynamic economic dispatch for wind-thermal power systems, to take into account ramping capabilities and costs of generators in their fast mode. In our model, the objective is to minimize a two-variable quadratic generator cost function depending on both output levels and ramp rates, and generator ramp rate limits are output dependent piece-wise linear functions. The model is solved by using existing quadratic programming methods, and is demonstrated by using numerical examples on the IEEE 30-bus system containing two 600MW thermal units with practical data. Results show that by using our model, unit ramping capabilities are better utilized in system dispatch to substantially save curtailed wind energy, and total generator costs are reduced.

Unveiling the physical nature of the oxygen-deficient conductive filaments (CFs) that are responsible for the resistive switching of the HfO

Intermodulation linearity is an important consideration for RF technologies. Third order intermodulation linearity is typically considered, as third order output is close to the fundamentals. Second order intermodulation outputs are far away from the fundamentals, and thus can be filtered [1]. However, the same second order nonlinearity also produces dc offset, which presents a significant problem for direct-conversion receivers [2]. While differential circuits can decrease second order nonlinearity, cancellation is not complete, and is worsened by transistor mismatch. We present here characterization of the second order intermodulation linearity on 200 GHz peak fT SiGe HBTs. The second order input intercept point, IIP2, is characterized on IC-VCE plane for different breakdown voltages. The measurement system is set up and calibrated according to [3]. Fig. 1 (a) and (b) show the measured IIP2 and fT versus IC for VCE = 1.0, 1.3, 1.6, and 1.9 V on a standard breakdown voltage (SBV) HBT. For comparison, the third order input intercept point (IIP3) is shown in Fig. 1 (c). IIP2 increases with IC before fT roll-off, and then decreases. A higher VCE effectively delays IIP2, fT and IIP3 roll-off overall. The impact is more obvious for IIP2 and IIP3 than for fT. Observe that the IIP3 peak is reached at a much smaller IC, well before peak fT is reached. IIP2 peaks either reside inside the flat fT region or closely lag behind fT roll-off. At high IC, higher VCE shifts IIP2 to higher level, implying that a higher VCE can be used to effectively improve IIP2 at higher currents. In Fig. 2 (a) and (b) , the current dependence of IIP2 and fT are compared for three HBTs of different breakdown voltage. IIP2 first increases with IC, peaks, and then decreases sharply before rising again. The IIP2 peak occurs approximately at the same current as the fT peak for all breakdown voltages. Before 1 mA, IIP2 is the same for all, indicating that the collector-base junction difference does not affect IIP2 so long as high injection does not occur. A higher VCE could be used with higher breakdown devices to extend the current range of high fT and IIP2, which is also confirmed by measurement. References [1] P. Wambacq, W. Sansen, Distortion Analysis of Analog Integrated Circuits, Kluwer, 1998 [2] B. Razavi, RF Microelectronics, Prentice-Hall, 2012 [3] G. Niu, et al., BCTM, pp. 1-4, 2006.

We evaluate the relative importance of different RF noise sources in SiGe HBTs through analytical expressions of noise correlation matrices for various representations. The relevant importances of terminal resistance thermal noise and correlated intrinsic terminal current noise are shown to vary with representation, and within the same representation, vary from element to element in the noise correlation matrix. An important analytical result is that the largest impact of base resistance on HBT noise figure is not the thermal noise it produces, but instead is its impact as an impedance element in affecting the propagation of intrinsic transistor terminal noise currents towards the extrinsic terminals. As a result, the importance of noise correlation in affecting transistor noise parameters is highly dependent on the base resistance, and for practical SiGe HBT technologies, correlated intrinsic terminal noise dominates over thermal noise in determining minimum noise figure.

We used next-generation sequencing technology to characterize 19 genomic simple sequence repeat (SSR) markers and 11 expressed sequence tag (EST) SSR markers from Leuciscus leuciscus baicalensis, a small freshwater fish that is widely distributed in Xinjiang, China. Primers were used to test for polymorphisms in three L. leuciscus baicalensis populations in Xinjiang. There were 4-27 (average 11.3) alleles (NA), the expected heterozygosity (HE) was 0.36-0.94 (average 0.75 ± 0.14), the observed heterozygosity (HO) was 0.37-1.00 (average 0.68 ± 0.18), and the polymorphism information content (PIC) was 0.31-0.93 (average 0.71). The averages of HE and PIC for the EST-SSR markers were slightly lower than for the genomic SSR markers. Genetic analysis of the three populations showed similar results for PIC, HE, and NA. Amplifications were performed in nine other species; the top three transferability values were for Rutilus lacustris (80%), Leuciscus idus (76.7%), and Phoxinus ujmonensis (63.3%), with the following average values: PIC (0.56, 4.46, and 0.52); NA (0.40, 3.00, and 0.32); and HO (0.44, 2.74, and 0.22), respectively. L. leuciscus baicalensis is one of the most important commercial fish in Xinjiang, but in recent years, fishery resources have decreased sharply owing to water conservation projects, unreasonable utilization, and invasion by alien species. These novel SSR markers are appropriate for studies involving fingerprinting, gene flow, genetic diversity, population structure, and molecular-assisted breeding, and could contribute to the conservation of L. leuciscus baicalensis.

Background/Aims : Defunctioning stoma is a common surgical procedure, it is now generally acknowledged that defunctioning stoma significantly reduce the rates of complications in colorectal surgery...

We realized a LD-side-pumped passively Q-switched Nd:YAG laser at 1123 nm by using a single walled carbon nanotube saturable absorber (SWCNT-SA). The SWCNT film was prepared by a vertical evaporation method on quartz substrate. At the pump power of 98 W, a maximum output power of 680 mW for a stable Q-switching operation was obtained. The repetition rate varied from 15.1 kHz to 37.2 kHz with the increase of pump power. The highest single pulse energy of 12.29 μJ occurs at the repetition frequency of 24.4 kHz. The corresponding pulse width was measured to be 2.2 μs.

In this study, an interactive fuzzy-boundary interval programming (IFBIP) method is developed to plan water resources management under uncertain conditions. IFBIP is capable of addressing dual uncertainties expressed as fuzzy-boundary intervals, as well as analyzing the reliability of satisfying (or the risk of violating) various constraints. The IFBIP method is then applied to the water resources management of the Hetao Basin (located in Inner Mongolia, China), one of the largest irrigation areas and the main food-producing region in the Yellow River Basin, where water scarcity is a major constraint for socioeconomic development. Results of water-allocation pattern and system benefit have been obtained under different feasibility degrees. Results reveal that agricultural irrigation is still the largest water consumer, compared with the other users such as industry, municipality, and livestock; meanwhile, irrigation water in each subarea is mainly from the Yellow River over the planning horizon. M...

We report on a LD-end-pumped passively Q-switched Nd:YAG ceramic laser by using a novel single wall carbon nanotube saturable absorber (SWCNT-SA). The SWCNT wafer was fabricated by electric Arc discharge method on quartz substrate with absorption wavelength of 1064 nm. We firstly investigated the continuous wave (CW) laser performance and scattering properties of Nd:YAG ceramic sample. For the case of passively Q-switched operation, a maximum output power of 376 mW was obtained at an incident pump power of 8.68 W at 808 nm, corresponding to an optical–optical conversion efficiency of 4.3%. The repetition rate as the increase of pump power varied from 14 to 95 kHz. The minimum pulse duration of 1.2 μs and maximum pulse energy of 4.5 μJ was generated at a repetition rate of 31.8 kHz.

Although wetlands are well known as one of the most important ecosystems in the world, there are still few global wetland mapping efforts at present. To evaluate the wetland-related types of data accurately for both the Global Land Cover 2000 (GLC2000) data set and MODIS land cover data set (MOD12Q1), we used the China wetland map of 2000, which was interpreted manually based on Landsat TM images, to examine the precision of these global land cover data sets from two aspects (class area accuracy, and spatial agreement) across China. The results show that the area consistency coefficients of wetland-related types between the two global data sets and the reference data are 77.27% and 56.85%, respectively. However, the overall accuracy of relevant wetland types from GLC2000 is only 19.81% based on results of confusion matrix of spatial consistency, and similarly, MOD12Q1 is merely 18.91%. Furthermore, the accuracy of the peatlands is much lower than that of the water bodies according to the results of per-pixel comparison. The categories where errors occurred frequently mainly include grasslands, croplands, bare lands and part of woodland (deciduous coniferous forest, deciduous broadleaf forest and open shrubland). The possible reasons for the low precision of wetland-related land cover types include (1)the different aims of various products and therefore the inconsistent wetland definitions in their systems; (2) the coarse spatial resolution of satellite images used in global data; (3) Discrepancies in dates when images were acquired between the global data set and the reference data. Overall, the unsatisfactory results highlight that more attention should be paid to the application of these two global data products, especially in wetland-relevant types across China.

A powerful and stable LD end pumped Nd:YVO4 passively mode-locking oscillator by SESAM was demonstrated. At the pumping power of 30 W, 7 W output was obtained with repetition rate of 79.5 MHz and pulse duration of 15 ps. The beam quality factors M 2 were measured to be 1.30 and 1.33, respectively.

An all-fiber high-energy nonlinear chirped-pulse amplification system with two-stage double-cladding fiber amplifiers is presented in this paper. It generates pulses with the energy up to 10 μJ at 20 kHz repetition rate and total accumulated nonlinear phase shift as large as 12.8π. The pulses can be compressed to 137 fs with the compensation of mismatched third-order dispersion by self-phase modulation in the fiber amplifiers.

We present a picosecond laser system with high energy by technologies of cavity dumping and amplifying. Firstly, pulses with 10 ps and ∼520 nJ were obtained by cavity-dumped mode-locked laser at 10 kHz repetition rate. Secondly those pulses were seeded into a side-pumped regenerative amplifier (RA). Then pulses output from the regenerative amplifier were amplified by two four-pass post amplifiers. From the laser system pulses with an average power of 30 W corresponding to 3 mJ pulse energy were achieved with the pulse-width of 25.4 ps at repetition rate of 10 kHz.

In this paper, we describe a compact all-fiber-path picosecond pulse based on Ytterbium doped fiber oscillator. A home-made novel SESAM mounted on fiber is reported, by which stable mode locking is obtained. The SESAM possesses the low saturation flux 20 μJ/cm2 (versus prior low saturation flux 32 μJ/cm2), which effectively reduces the pump power threshold of mode locking. The fiber laser generates 15 ps pulse trains without a dispersive delay line or anomalous dispersion in the cavity. Mode locking pulse with 30 MHz basic repetition-rate was produced, with 10–30 mW scale average output power at 1064 nm. Through 60 h of uninterrupted laser operating, mode locking is steady as ever.

This work presents a study of the epitaxial growth of Ge on Si (111) using a Gd2O3 crystalline template. A smooth two-dimensional Ge layers is obtained from the coalescence of initially three-dimensional Ge islands grown in the Volmer–Weber mode. Ge takes its bulk lattice parameter at the very early stages of its growth. A detailed x-ray pole figure analysis reveals that the epitaxial relationship between the layers and the Si substrate is [1–10]Ge(111)∥[−110]Gd2O3(111)∥[1–10]Si(111) and that microtwins are formed in the Ge layer.

SiGe HBTs, like other semiconductor devices, are in general nonlinear circuit elements. The exponential IC-VBE nonlinearity common to all bipolar transistors represents the strongest possible nonlinearity for all devices in which currents are produced by drift and diffusion of electrons and holes. Nonlinearity is desired for frequency translation and oscillation, but undesired for signal reception, amplification and transmission. In this talk we will review the fundamentals of various physical nonlinearities in SiGe HBTs, their complex interactions, experimental biasing current and voltage dependence of 2nd and 3rd order intercept points, IP2 and IP3, as well as recent developments in compact modeling of linearity using Mextram, an industry standard transistor model we are developing, for both common-base and common-emitter configurations. From a circuit point of view, the consequence of nonlinear IC-VBE is to make effective transconductance gm,eff a function of small signal base-emitter junction voltage vbe , as opposed to a constant in a linear circuit. The nonlinear contributions in general increase with vbe, which in general decreases with increasing biasing current before high injection, making gm,eff closer to a constant. The linearity of a SiGe HBT amplifier can therefore generally be improved by increasing biasing current. At radio frequencies, however, at relatively higher current, the 3rd order current produced by the nonlinear base-collector junction capacitance becomes important, and can interact with the 3rd order currents produced by the nonlinear IC, leading to a peak of IP3. Likewise, at higher VCB, as found in the common-base stage of a cascode amplifier, avalanche multiplication current Iavl produces an important 3rd order current that interacts with 3rd order currents from IC (without avalanche) and CBC, which can lead to a peak of IP3 in VCB dependence. Such peaks of IP3 are important for transistor biasing and sizing in circuit design, but also pose more stringent requirements on compact modeling than DC I-V and linear s-parameters. While both CBC and Iavl are straightforward to characterize and model at low currents, difficulties in both characterization and modeling increase at higher currents of interest. Latest Mextram 505.00 provides several options for modeling VCB and IC dependence of CCB, which give similar y-parameters but different IP3, particularly for common-emitter configuration, as illustrated in Figure 1. New CCB model options for junction voltage and capacitance smoothing, swvjunc=1, swvchc=0, lead to much better modeling of peak OIP3 than swvjunc=2, swvchc=1, which reduces to 504.12. Recommendations of best options and parameters for accurate modeling of IP3 will be made. While CCB model also affects IC nonlinearity through Early effect, we will show that its impact on IP3 is primarily through capacitive current. We will also show that the IC dependence of CCB is import to include for IP3. Common-base transistors often operate at higher VCB and hence with significant amount of Iavl. Mextram 505.00 has a new Iavl model that allows better current dependence and temperature dependence. Figure 2 shows this new avalanche model (swavl=1) has improved current dependence modeling of OIP3 over 504.12 (swavl=2 reduces model to 504.12) for a common-base SiGe HBT. Figure 1

A vertical NPN transistor is typically built on a p-type substrate, which gives rise to parasitic PNP transistor action when the NPN base-collector junction, which is also the PNP emitter-base junction, is forward biased. In Mextram and Hicum, the PNP base terminal is attached to the NPN collector node that corresponds to the epi layer / buried layer interface, with VB1C1 as the PNP control emitter-base voltage, as illustrated in Fig. 1. A long physics based derivation to justify this choice was given in [1]. In Vbic, an option is provided to use both VB1C1 and VBC2 as PNP control voltage, with VBC2 as default. Using B or B1 is insignificant typically, while the difference between C1 and C2 is. While such approach generally works well for high speed transistors, for high voltage transistors, we experience great difficulty in fitting the substrate current at high VBE when the electrical base pushes out towards the collector, causing the internal NPN base-collector junction to be forward biased despite a reverse bias on the NPN external base-collector junction. Holes injected from the base diffuse downward towards the buried layer, and are retarded by a high electric field near the epi/buried layer interface, making the actual physics of hole transport much more complex than in a standalone PNP transistor. Fig. 2 (a) shows the best results one can possibly get with the standard Mextram model for a typical VBE sweep at VBC=0, -2 and -5V, VBS=2V. It is important to note that the VB1C1 = VBC + ICRCC –IBRBC in Mextram terms, with RCC and RBC being extrinsic collector and base resistances, respectively. Fig. 2 (b) shows the simulated VB1C1. For VBC=-2 and -5V, VB1C1 is still largely negative, while in measurement substrate current starts to rise quickly around VBE of 0.8V, indicating a rapid turn on of PNP action. This clearly suggests that the theory of [1] does not apply to these transistors, and improved modeling of PNP is needed. An alternative is to use the intrinsic base-collector junction voltage VB2C2, i.e. VB2C2* in Mextram, as the PNP substrate current control voltage, which was suggested in [2]. This leads to a higher Isub as shown in Fig. 3 (a) and (b). However, the onset of Isub, and the high VBE values of IB are all overestimated. IC is underestimated due to overestimation of IBRBC. This, however, does suggest that the PNP action is in fact related to some kind of internal base-collector junction bias which relates to the epi layer state. Here we propose a new model for the effective PNP emitter-base junction voltage, based on Mextram’s epi layer model. To minimize coupling of PNP and NPN modeling, we create a separate VB2C2, denoted as VB2C2** , and calculate it exactly the same way VB2C2* is calculated from epi layer current IC1C2 and VB2C1, but with a set of dedicated epi layer model parameters, i.e. rcv, scrcv, ihc, axi and vdc. In parameter extraction, the regular epi layer model parameter set is used for fitting Gummel, output and fT curves, while this new set of Isub dedicated epi layer model parameters is used for fitting substrate current. Fig. 4 (a) and (b) show modeling results of our new model. IB and Isub are much better fitted, including accurate modeling of the onset of Isub. [1] W. D. Mack and M. Horowitz, “Measurement of series collector resistance in bipolar transistor,” IEEE J. Solid-State Circuits, vol. SC-17, pp. 767-773, Aug. 1982. [2] J. -S. Park, A. Neugroschel, V. de la Torre and P. J. Zdebel, “Measurement of collector and Emitter Resistances in Bipolar Transistors,” IEEE Transactions on Electron Devices, vol. 38, pp. 365-372, Feb. 1991. Figure 1

We report on the fabrication and electrical characterization of bottom gate thin-film transistors (TFTs) based on a sol-gel derived ZnO channel layer. The effect of annealing of ZnO active channel layers on the electrical characteristics of the ZnO TFTs was systematically investigated. Photoluminescence (PL) spectra indicate that the crystal quality of the ZnO improves with increasing annealing temperature. Both the device turn-on voltage (Von) and threshold voltage (VT) shift to a positive voltage with increasing annealing temperature. As the annealing temperature is increased, both the subthreshold slope and the interfacial defect density (Dit) decrease. The field effect mobility (?FET) increases with annealing temperature, peaking at 800 �C and decreases upon further temperature increase. An improvement in transfer and output characteristics was observed with increasing annealing temperature. However, when the annealing temperature reaches 900 �C, the TFTs demonstrate a large degradation in both transfer and output characteristics, which is possibly produced by non-continuous coverage of the film. By using the temperature-dependent field effect measurements, the localized sub-gap density of states (DOSs) for ZnO TFTs with different annealing temperatures were determined. The DOSs for the subthreshold regime decrease with increasing annealing temperature from 600 �C to 800 �C and no substantial change was observed with further temperature increase to 900 �C. - 2017 Author(s). The project was funded by AU-IGP. Park would like to thank Walter Professorship for partial support of this project. Scopus

TADP, 2-(1H-1, 2, 4-triazol-1-yl)-1-hydroxyethane-1, 1-diphosphonic acid, was synthesized by three step reactions from the raw material 1H-1, 2, 4-triazole. 99Tcm-TADP was prepared with 5 mg TADP at pH 7.0 by joining 99TcmO4−with SnCl2–2H2O in aqueous solution for 10 min at room temperature. Both labeling yield and radiochemical purity of 99Tcm-TADP were more than 95%. The biodistribution in rats and bone scan in rabbits were also studied. The uptake of organ was expressed as %ID/g. The results showed that the bone uptake is up to 17.17%ID/g which is the maximum of bone uptake at 30 min after injection of 99Tcm-TADP in rats, bone-to-muscle and bone-to-blood uptake ratios were 61.32 and 13.21, respectively. The clear bone image of rabbit was obtained at 120 min after injection of 99Tcm-TADP and clearance in soft tissue was visible. The preparation of 99Tcm-TADP was convenient and 99Tcm-TADP exhibited high uptake in bone, and it would be a potential new bone imaging agent.

Wingless and int homologue (Wnt) family proteins have been shown to have important roles in the decision of cell fate and behavior at multiple stages during the development and tumorigenesis. One of the Drosophila segment polarity genes, porcupine (porc) gene, encodes an evolutionarily conserved endoplasmic reticulum membrane protein involving in the post-translational processing of the Wnt family proteins. Here, we report that human homologue of Drosophila porc gene, PPN/MG61, was abundantly expressed in human cancer cell lines, but not in normal cells. We also found that PPN/MG61 was overexpressed in primary lung cancer tissue samples, compared to their matched normal tissue samples. Furthermore, when we used small interfering RNA to knock down PPN/MG61 mRNA in lung cancer cells expressing the gene, we observed apoptosis induction, along with decreased activity of Wnt pathway in those lung cancer cells. These data suggest that PPN/MG61 may be a novel marker for human lung cancer and that post-translational modification of the Wnt signal molecules by PPN/MG61 may be important for the function of Wnt pathway in lung cancer.

Maize yield is severely affected by soil salinity. In an effort to engineer maize for improved salt tolerance, embryogenic calli of maize were co-bombarded with plasmids containing Oryza sativa Na + /H + antiporter gene (OsNHX1) and bar genes. For the molecular analysis of putative transgenic samples, PCR, Southern and Northern blots were carried out. The maize plants over-expressing OsNHX1 accumulated more biomass when grown in the presence of 200mM NaCl in greenhouse conditions. Higher Na + and K + content was observed in transgenic leaves than in wildtype leaves when treated with 100~200mM NaCl, while the osmotic potential and the proline content in transgenic leaves was lower than in wild-type maize. A field trial revealed that the transgenic maize plants produced higher grain yields than the wild-type plants at the vegetative growth stage. These results demonstrate that the OsNHX1 gene was successfully transferred into Zea mays, and the salt-tolerance of transgenic maize was improved by overexpression of the OsNHX1 gene.

Metamizole sodium was chosen as a representative of unstable analytes for investigation by discussing the effects of oxygen and solvent on its degradation reaction using the capillary electrophoresis technique. A possible degradation mechanism was deduced from the observed behavior and was confirmed by infra-red spectroscopic study. The degradation reaction could be inhibited obviously by methanol instead of water as the solvent of analyte. Under the optimized conditions: separation voltage of 20 kV, and 5 mmol/L disodium hydrogen phosphate and 5 mmol/L borax with 10% methanol (pH 9.12) as the running buffer, the standard curve of metamizole sodium was linear in a range of 3.77—74.07 mg/L. A satisfactory result was achieved when the technique was used to detect metamizole sodium in tablet.