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Thermally induced thunderstorm simulations were conducted with the Weather Research and Forecasting (WRF) Model in an idealized configuration to investigate the associated error growth and predictability. We conducted identical twin experiments with different topography and background winds to assess the impacts of these factors. The results showed that mountain topography restrains error growth at the early stage of convection development. This topographic effect is sensitive to mountain geometry and background winds: it was more noticeable in cases with higher and narrower mountains and difficult to see without background wind. The topographic effect and its sensitivity resulted from the different natures of convection initiation. However, the topographic effect became less apparent when moist convection continued growing and triggered rapid error growth. The predictability of thunderstorms is then limited at the timing after the convective activity reached its maximum. A smaller initial error or starting a simulation at a later time did not break this timing of predictability limit. Mountain topography also limitedly affected the timing of the maximum convective activity and the predictability limit. In contrast, background flows changed the convection evolution and the following predictability. The predictability limit assessed by rainfall suggested other aspects of the topographic effect. The domain-scale rainfall distribution and the intense accumulated rainfall can be adequately captured in the presence of mountains.

Taiwania cryptomerioides Hayata is an endangered relict plant belonging to Taxodiaceae, and it is also an endemic plant to China. The decay-resistant of Taiwania timber can provide highly quality wood for building and furniture. Plenty of regenerative of leaves of T. cryptomerioides also has been used as a resource for the discovery of new dimeric diterpenoids. In a search for structurally diverse dimeric diterpenoids and potent bioactive isolates, ten new heterodimeric diterpenoids, taiwaniadducts K-T (1-4, 6, 8-11, 14), along with five known ones (5, 7, 12, 13, 15), were isolated from the leaves of T. cryptomerioides. These new compounds were defined by comprehensive spectroscopic analyses, putative biosynthetic pathways, and the value of optical. Biologically, anti-multidrug resistance (MDR) activities of compounds were evaluated. Compounds 4 and 10 exerted a 9.18-fold potentiation effect on bortezmib (BTZ) susceptibility at a tested concentration (20 μM) better than the positive control verapamil. The research of the leaves of T. cryptomerioides not only added the new data to the structural diversity and activities of dimeric diterpenoids but also could provide support for the medical and industrial application of the leaves of this endangered relict plant.

Additional file 1: Supplementary figure 1. Raw images of western blot (including blot images as they are, with the membrane edges and all repeats) represent the AGA (0, 10, and 20 mg) extract effects on three different cell lines SW620, SW480, and HT29 to investigate expression of cell cycle proteins. (A) Represent the cdk4, (B) cdk2, (C) p21, and (D) cdk6 protein expression after AGA extract effect on three colon cancer cell lines. All data were represented with their three repeats; and red colour brackets in original blot images indicates edges of membrane in each images that used in manuscript of figure 4ABC. Supplementary figure 2. Raw images of western blot (including blot images as they are, with the membrane edges and all repeats) represent the AGA (0, 10, and 20 mg) extract effects on three different cell lines SW620, SW480, and HT29 to investigate expression of cell cycle proteins. (A) Represent the cdk4, (B) cdk2, (C) p21, and (D) cdk6 protein expression after AGA extract effect on three colon cancer cell lines. All data were represented with their three repeats; and red colour boxes in original blot images indicates that images are used in manuscript of figure 4ABC. Supplementary figure 3. Raw images of western blot (including blot images as they are, with the membrane edges and all repeats) represent the AGA (0, 10, and 20 mg) extract effects on three different cell lines SW620, SW480, and HT29 to investigate expression of apoptosis. (A) Represent the p53, (B) Bax, and (C) Caspase 9 protein expression after AGA extract effect on three colon cancer cell lines. All data were represented with their three repeats; and red colour brackets in original blot images indicates edges of membrane in each images that used in manuscript of figure 6ABC. Supplementary figure 4. Raw images of western blot (including blot images that used in manuscript) represent the AGA (0, 10, and 20 mg) extract effects on three different cell lines SW620, SW480, and HT29 to investigate expression of apoptosis. (A) Represent the p53, (B) Bax (in bax blot SW480 mention as 20, 10, 0, but in manuscript used as 0, 10, 20), and (C) Caspase 9 protein expression after AGA extract effect on three colon cancer cell lines. All data were represented with their three repeats; and red colour boxes in original blot images indicates that images are used in manuscript of figure 6ABC. Supplementary figure 5. Raw images of western blot (including blot images as they are, with the membrane edges and all repeats) represent the AGA (0, 10, and 20 mg) extract effects on three different cell lines SW620, SW480, and HT29 to investigate expression of B-actin (A) Represent the original blot images of B-actin with repeats; red colour brackets in original blot images indicates edges of membrane in each images that used in manuscript of figure 4ABC and figure 6ABC. (B) Original blot images of B-actin with repeats, red colour boxes in original blot images indicates that images are used in manuscript of 4ABC and figure 6ABC.

Identical twin experiments with and without topography are conducted with the Weather Research and Forecasting (WRF) model in an idealized framework to investigate the impact of topography on the initial error growth associated with moist convection. A topography is set as a single Gaussian shape mountain with a peak height of about 1000 m. Both experiments show clear diurnal cycles, while moist convection develops earlier and organizes to a larger size in the experiment with topography. To evaluate the initial error growth, a metric referred to as moist difference total energy (MDTE) is proposed to represent the differences between the two simulations in twin experiments. The horizontal spatial distribution, temporal evolution, and horizontal wavenumber space of the MDTE suggest that the error growth is greatly dominated by the different features of convection development between the two experiments. The analysis based on individual cloud areas shows that the convective clouds developing over the mountain have smaller MDTE at the early stage of development.

Sampling error stems from the use of ensemble-based data assimilation (EDA) with a limited ensemble size and can result in spurious background error covariances, leading to false analysis corrections. The WRF-LETKF radar assimilation system (WLRAS) is performed separately with 256 and 40 members to investigate the characteristics of convective-scale sampling errors in the EDA and its impact on precipitation prediction based on a heavy rainfall event on 16 June 2008. The results suggest that the sampling errors for this event are sensitive to the relationships between the simulated observations and model variables, the intensity of reflectivity, and how the prevailing wind projects to the radial wind in the areas that the radar cannot resolve U or V wind. The sampling errors lead to an underprediction of heavy rainfall when the horizontal localization radius is inadequately large, but this can be mitigated when a more accurate moisture condition is provided. In addition, being able to use a larger vertical localization plays an important role in providing necessary adjustments for representing the vertical thermodynamical structure of convection, which further improves precipitation prediction. A strategy mitigating the impact of sampling errors associated with the limitation of radial wind measurement by inflating the observation error over sensitive areas can bring benefits to precipitation prediction.

This paper proposes a high-speed gate driver integrated circuit (IC) for gallium nitride (GaN) synchronous buck converter which includes an adaptive bang-bang deadtime modulator to eliminate the power loss caused by reverse conduction and prevent high side and low side shoot-through. Fabricated in a 0.25-μm Bipolar-CMOS-DMOS process, the proposed GaN driver integrated circuit (IC) enables buck converter to operate at 10MHz switching frequency and adjust minimal dead-time to as low as 0.4ns under heavy load condition.

GaN devices operating at reverse conduction region causing excessive conduction loss. Therefore, the GaN based switching converters are required to minimize the dead-time. This paper proposes a novel highly digitally adaptive dead-time control for GaN driver. A driver integrated circuit (IC) is designed in 0.18μm BCD GEN2 process to verify the concept. The measurement result achieves 0.7ns dead-time at 2A and efficiency can improve 2.1% at 2A full load compared to 10ns fixed dead-time counterpart.

Targeting on high switching frequency gallium nitride (GaN) dc-dc buck converter, this paper presents a 10MHz switching frequency gate driver IC for GaN based synchronous buck converter with 12V maximum input voltage. The proposed bootstrap circuit prevent overcharge issue in GaN application, and the dynamic pull-up resistor gate driver suppress the gate-to-source voltage spike 400mV effectively and the rising time is 2.3ns. A low propagation delay and high common-mode transient immunity level shifter is also proposed for high speed application achieves the turn on propagtion delay is 480.9ps and the turn off propagation delay is 633.4ps by simulation result. This work was fabricated in a 0.25-μm TSMC Bipolar-CMOS-DMOS process.

Targeting on gate ringing suppression in gallium nitride (GaN) dc-dc converter. This paper presents a 10MHz switching frequency gate driver for GaN-based buck converter which including a fixed dead time modulator to prevent high side and low side shoot-through issue, active bootstrap control is necessary for GaN application because of the leakage of body diode to control bootstrap circuit voltage under 5V, gate ringing suppression gate driver is used to provide multi-slew rate driving current furthermore reducing voltage spike appears at power devise and a high voltage level shifter. Ths work fabricated in a 0.25-μm Bipolar-CMOS-DMOS process.

El adenocarcinoma de páncreas (CP) es una enfermedad altamente desafiante con una tasa de supervivencia a 5 años de menos del 5%. Aunque la mayoría de los pacientes presentan enfermedad avanzada, los mejores resultados se observan en aquellos sometidos a resección de su tumor primario en centros especializados. Se considera resecable al diagnóstico; en el 15% de los casos y con tratamiento adyuvante (TA) determina una supervivencia mediana de 24 a 28 meses. El objetivo fue conocer la evolución oncológica de los mismos. El estudio es retrospectivo, observacional y multicéntrico. Se evaluaron pacientes incluidos en la plataforma virtual RITA (Registro Institucional de Tumores de Argentina) diseñada por el Instituto Nacional del Cáncer para tumores hepato-hilio-pancreáticos entre el 1/06/13 y el 31/07/16 con diagnóstico de CP tratados con cirugía seguido de algún TA, que asistieron a los centros participantes. De un total de 337 pacientes, 50 fueron sometidos a cirugía seguida de TA. El 48% fueron hombres. La edad media fue de 60 años. El 90% (45) presentó un PS 0/1 y el 98% adenocarcinoma. Se destaca que el 70% (35) presentó estadio II, seguido del 18% (9) con estadio I. El 70% (35) fue tratado con esquema de quimioterapia adyuvante. La mediana de supervivencia fue 27.3 meses. A pesar de las limitaciones en el número de la muestra, la heterogeneidad en los tratamientos y el análisis retrospectivo, los resultados finales de nuestro estudio son similares a los datos de la literatura.

The high-power light-emitting diode (LED) lighting is especially essential in the high-temperature applications, such as the street lighting and automotive lighting. However, there is more than 70% of electrical power converted into heat due to the low electrical-optical conversion efficiency. Because of the characteristics of the semiconductor, the electrical property of LEDs is sensitively varying with operating temperature. These deviations affect the measurement of light and electricity. In this paper, the steady-state thermal measurement techniques developed by the National Institute of Standards and Technology are used to study the deviation of thermal resistance in different electrical and thermal conditions. The consistent trends of simulations and experiments represent that the design of the heat dissipating path and geometry affects the measurement of thermal resistance.

In this research, 425 female college students aged from 18 to 26 were selected as samples, using 3D body scanner to get the body Point-cloud image, and measure the thickness, width and girth size of characteristic body parts(waist, abdomen, hip) ; By studying the circumferences sections of characteristic body parts, body type is classified according to thickness / width ratio; The correlation of circumference with thickness and width is analyzed, the circumference calculating equations for different body size is obtained, then the reasonableness of the method is tested, which providing a reference for the human body circumference automatically generated from 2D images.

In this research, 425 female students were selected as the research objects. Point clouds were obtained by 3D body scanner , then the characteristics of female lower body parts’ (waist, abdomen, buttock) section shapes were identified .And the sizes of the width and thickness were measured by a data acquisition software named Imageware.The front and back circumferences were analysed by software of SPSS16.0.This research is main to provide a new method to divide and calculate body front and back circumferences, laying the foundation for fitting of women clothes.

In this study, three-dimensional body measurement instrument was used to measure 425 female bodies aged from 18 to 26 years old. Imageware software was used to obtain the point cloud images of female body and measure their key parts’ altitudes (waist, abdomen, buttocks, thigh, knee). Then, SPSS16.0 was used to analyze the key parts’ altitudes and height to find the regression equations of them. Finally, the altitude rules of young female lower body were tested to ensure its correctness. In this paper, the result can provide basis of altitude confirmation rules for the study on automatically pattern design system of women skirts.

In this paper, 357 female students in soochow university which are 18 to 26 years old were selected as subjects. Front, back and side photos are taken by using digital camera, and then photo manipulation was done to amplify the contrast between the human body and background. The width and thickness of human characteristic positions were measured by COREDRAW software. Meanwhile, the girth of each position was got by manual measurement, and the width and thickness of human characteristic positions were extracted by MATLAB. Finally the girth, width and thickness were analyzed by SPSS to obtain the girth calculative rules, and the error analysis was done to verify the veracity. The result showed that the regression fitting was feasible and accurate.

The design of a solar power management system (SPMS) for an experimental unmanned aerial vehicle (UAV) is summarized. The system will provide power required for the on-board electronic systems on the UAV. The power management system mainly consists of the maximum power point tracking (MPPT), the battery management, and the power conversion stages. The MPPT stage attempts to obtain the maximum power available from the solar cell panels. The battery management stage monitors and controls the charge and discharge processes of the Li-ion polymer battery modules. The last stage is for power conversion that consists of dc/dc synchronous buck converters to generate +5 V and +12 V powers for the on-board computers and other electronic circuitries.

Alternating copolymers containing bipyridine and phenylene vinylene were synthesized through a Wittig condensation reaction of their corresponding diphosphonium salts and dialdehydes. The molecular weights of the resulting polymers were relatively low because of the low solubility in the reaction solvents. The optical properties of the polymers were substantially affected by the repeating units of phenylene vinylene. The absorption spectra of the copolymers in the solid state exhibited a bathochromic shift compared to those carried out in solution. The effective conjugation length could be extended with the addition of Cu2+, Ni2+, and Zn2+ ions into the polymer solutions in a 1:1 ratio of the bipyridine to the phenylene vinylene units. All of the polymer solutions behaved as a turn-off fluorescent chemosensor upon the addition of a variety of the metal ions. The sensing behavior to various metal ions revealed that the polymers were highly sensitive to the Cu2+, Ni2+, and Zn2+ ions. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42795.