402 research outputs found
The Design of Compass/BeiDou Navigation Satellite Terminal for Migrant Bird Research
A terminal of Compass Navigation Satellite System (CNSS), which can not only support BeiDou-1 and BeiDou-2 but also support Global Positioning System (GPS), is designed to research the activities of the migrant birds, with our novel design of a multiband antenna. By a high-density integration, this terminal is designed with a compact size and light weight. When the terminal is assembled to a whooper swan, its flying trace is recorded by the CNSS, which is in agreement with that of GPS. The flying route map based on the CNSS is useful to check the situation and habit of the migrant bird, which is important for animal protection and bird flu outbreak prediction
Estimating Effects of Long-Term Treatments
Estimating the effects of long-term treatments in A/B testing presents a
significant challenge. Such treatments -- including updates to product
functions, user interface designs, and recommendation algorithms -- are
intended to remain in the system for a long period after their launches. On the
other hand, given the constraints of conducting long-term experiments,
practitioners often rely on short-term experimental results to make product
launch decisions. It remains an open question how to accurately estimate the
effects of long-term treatments using short-term experimental data. To address
this question, we introduce a longitudinal surrogate framework. We show that,
under standard assumptions, the effects of long-term treatments can be
decomposed into a series of functions, which depend on the user attributes, the
short-term intermediate metrics, and the treatment assignments. We describe the
identification assumptions, the estimation strategies, and the inference
technique under this framework. Empirically, we show that our approach
outperforms existing solutions by leveraging two real-world experiments, each
involving millions of users on WeChat, one of the world's largest social
networking platforms
Up-regulation on cytochromes P450 in rat mediated by total alkaloid extract from Corydalis yanhusuo
BACKGROUND: Yanhusuo (Corydalis yanhusuo W.T. Wang; YHS), is a well-known traditional Chinese herbal medicine, has been used in China for treating pain including chest pain, epigastric pain, and dysmenorrhea. Its alkaloid ingredients including tetrahydropalmatine are reported to inhibit cytochromes P450 (CYPs) activity in vitro. The present study is aimed to assess the potential of total alkaloid extract (TAE) from YHS to effect the activity and mRNA levels of five cytochromes P450 (CYPs) in rat. METHODS: Rats were administered TAE from YHS (0, 6, 30, and 150Â mg/kg, daily) for 14Â days, alanine aminotransferase (ALT) levels in serum were assayed, and hematoxylin and eosin-stained sections of the liver were prepared for light microscopy. The effects of TAE on five CYPs activity and mRNA levels were quantitated by cocktail probe drugs using a rapid chromatography/tandem mass spectrometry (LC-MS/MS) method and reverse transcription-polymerase chain reaction (RT-PCR), respectively. RESULTS: In general, serum ALT levels showed no significant changes, and the histopathology appeared largely normal compared with that in the control rats. At 30 and 150Â mg/kg TAE dosages, an increase in liver CYP2E1 and CYP3A1 enzyme activity were observed. Moreover, the mRNA levels of CYP2E1 and CYP3A1 in the rat liver, lung, and intestine were significantly up-regulated with TAE from 6 and 30Â mg/kg, respectively. Furthermore, treatment with TAE (150Â mg/kg) enhanced the activities and the mRNA levels of CYP1A2 and CYP2C11 in rats. However, the activity or mRNA level of CYP2D1 remained unchanged. CONCLUSIONS: These results suggest that TAE-induced CYPs activity in the rat liver results from the elevated mRNA levels of CYPs. Co-administration of prescriptions containing YHS should consider a potential herb (drug)âdrug interaction mediated by the induction of CYP2E1 and CYP3A1 enzymes
PHOTOMETRIC OBSERVATION OF 3024 HAINAN, 3920 AUBIGNAN, AND 5951 ALICEMONET
Three minor planets were measured photometrically between 2012 September 4 and 21 using the SARA (Southeastern Association for Research in Astronomy) South telescope, located in Cerro Tololo Inter-American Observatory. The following synodic periods were found: 3024 Hainan, P = 11.785 ± 0.005 h; 3920 Aubignan, P = 4.4762 ± 0.0005 h; and 5951 Alicemonet, P = 3.8871 ± 0.0005 h
Exploring the electrochromic properties of poly(thieno[3,2-b]thiophene)s decorated with electron-deficient side groups
Two novel thieno[ 3,2-b] thiophene (TT)/3,4-ethylenedioxythiophene (EDOT)-based compounds of 2,5( EDOT-TT-EDOT) type bearing electron-withdrawing side groups (4-cyanophenyl or 4-pyridyl) at 3,6-positions of the TT moiety have been synthesized. Their electropolymerization leads to electroactive conjugated polymers, P(CNPh-ETTE) and P(Py-ETTE), which possess electrochromic properties changing the color from purple to pale grey-blue or from sand brown to pale grey-green, respectively. Cyclic voltammetry and spectroelectrochemical experiments reveal that functionalization with electron-withdrawing side groups decreases the HOMO and LUMO energy levels and contracts the band gap of materials. Both new polymers demonstrated extremely short response times of 0.9-1.1 s for bleaching and 0.34-0.35 s for coloring. P(CNPh-ETTE) and P(Py-ETTE) polymers showed reasonably good contrast (16-23%) and coloration efficiency (120-190 cm(2) C-1) in the visible region (at the maxima of their pi-pi* transitions, 540/570 nm), and high contrast and coloration efficiency in the near-infrared region (50-62% and 324-440 cm(2) C-1 at 1500 nm, respectively). While the stability of the pyridine-functionalized polymer, P(Py-ETTE), was shown to be low (with unstable charge-discharge characteristics, presumably due to the protonation of the pyridine ring during the redox process), P(CNPh-ETTE) demonstrated superior electrochromic performance retaining 91-96% of its electroactivity after 2000 cycles between -0.5 and +1.0 V. DFT calculations on these and related EDOT-TT-EDOT polymers reported by us early have been presented and analyzed to understand the structure-property relationships in this class of electrochromic polymers.Shenzhen Key Laboratory of Organic Optoelectromagnetic FunctionalMaterials of Shenzhen Science and Technology Plan [ZDSYS20140509094114164]; Shenzhen Peacock Program [KQTD2014062714543296]; Shenzhen Science and Technology Research Grant [JCYJ20140509093817690, JCYJ20160331095335232]; Nanshan Innovation Agency Grant [KC2015ZDYF0016A]; Guangdong Key Research Project [2014B090914003, 2015B090914002]; Guangdong Talents Project; National Basic Research Program of China (973 Program) [2015CB856505]; Natural Science Foundation of Guangdong Province [2014A030313800]; Guangdong Academician Workstation [2013B090400016]SCI(E)ARTICLE4769-784
PHOTOMETRIC OBSERVATIONS OF 782 MONTEFIORE, 3842 HARLANSMITH, 5542 MOFFATT, 6720 GIFU, AND (19979) 1989 VJ
Five solar system minor planets were measured photometrically between 2012 October and December using the SARA (Southeastern Association for Research in Astronomy) telescopes located in Kitt Peak National Observatory in USA and Cerro Tololo Inter-American Observatory in Chile. The following synodic periods were found: 782 Montefiore P = 4.0728 ± 0.0006 h; 3842 Harlansmith, P = 2.7938 ± 0.0005 h; 5542 Moffatt P = 5.187 ± 0.001 h; 6720 Gifu, P = 4.231 ± 0.001 h; and (19979) 1989 VJ, P = 7.568 ± 0.005 h
Integrated microfluidic systems with sample preparation and nucleic acid amplification
Rapid, efficient and accurate nucleic acid molecule detection is important in the screening of diseases and pathogens, yet remains a limiting factor at point of care (POC) treatment. Microfluidic systems are characterized by fast, integrated, miniaturized features which provide an effective platform for qualitative and quantitative detection of nucleic acid molecules. The nucleic acid detection process mainly includes sample preparation and target molecule amplification. Given the advancements in theoretical research and technological innovations to date, nucleic acid extraction and amplification integrated with microfluidic systems has advanced rapidly. The primary goal of this review is to outline current approaches used for nucleic acid detection in the context of microfluidic systems. The secondary goal is to identify new approaches that will help shape future trends at the intersection of nucleic acid detection and microfluidics, particularly with regard to increasing disease and pathogen detection for improved diagnosis and treatment
Nasal administration of interleukin-33 induces airways angiogenesis and expression of multiple angiogenic factors in a murine asthma surrogate
The Tâhelper cell type 2âpromoting cytokine interleukinâ33 (ILâ33) has been implicated in asthma pathogenesis. Angiogenesis is a feature of airways remodelling in asthma. We hypothesized that ILâ33 induces airways angiogenesis and expression of angiogenic factors in an established murine surrogate of asthma. In the present study, BALB/c mice were subjected to serial intranasal challenge with ILâ33 alone for up to 70 days. In parallel, ovalbumin (OVA) âsensitized mice were subjected to serial intranasal challenge with OVA or normal saline to serve as positive and negative controls, respectively. Immunohistochemical analysis of expression of von Willebrand factor and erythroblast transformationâspecificârelated gene, both blood vessel markers, and angiogenic factors angiogenin, insulinâlike growth factorâ1, endothelinâ1, epidermal growth factor and amphiregulin was performed in lung sections ex vivo. An established inâhouse assay was used to test whether ILâ33 was able to induce microvessel formation by human vascular endothelial cells. Results showed that serial intranasal challenge of mice with ILâ33 or OVA resulted in proliferation of peribronchial von Willebrand factorâpositive blood vessels to a degree closely related to the total expression of the angiogenic factors amphiregulin, angiogenin, endothelinâ1, epidermal growth factor and insulinâlike growth factorâ1. ILâ33 also induced microvessel formation by human endothelial cells in a concentrationâdependent fashion in vitro. Our data are consistent with the hypothesis that ILâ33 has the capacity to induce angiogenesis at least partly by increasing local expression of multiple angiogenic factors in an allergenâindependent murine asthma surrogate, and consequently that ILâ33 or its receptor is a potential novel molecular target for asthma therapy
Molecular engineering tuning optoelectronic properties of thieno[3,2-b]thiophenes-based electrochromic polymers
Thieno[3,2-b]thiophene (TT) monomers end-capped with 3,4-ethylenedioxythiophene (EDOT) moieties are electropolymerized to form pi-conjugated polymers with distinct electrochromic (EC) properties. Steric and electronic factors (electron donor and acceptor substituents) in the side groups of the TT core, as well as the structure of the polymer backbone strongly affect the electrochemical and optical properties of the polymers and their electrochromic characteristics. The studied polymers show low oxidation potentials, tunable from-0.78 to +0.30 V (vs. Fc/Fc(+)) and the band gaps from 1.46 to 1.92 eV and demonstrate wide variety of color palettes in polymer films in different states, finely tunable by structural variations in the polymer backbone and the side chains. EC materials of different colors in their doped/dedoped states have been developed (violet, deep blue, light blue, green, brown, purple-red, pinkish-red, orange-red, light gray, cyan and colorless transparent). High optical contrast (up to 79%), short response time (0.57-0.80 s), good cycling stability (up to 91% at 2000 cycles) and high coloration efficiency (up to 234.6 cm(2) C-1) have been demonstrated and the influence of different factors on the above parameters of EC polymers have been discussed.Shenzhen Key Laboratory of Organic Optoelectromagnetic Functional Materials of Shenzhen Science and Technology Plan [ZDSYS20140509094114164]; Shenzhen Peacock Program [KQTD2014062714543296]; Shenzhen Science and Technology Research Grant [JCYJ20140509093817690]; Nanshan Innovation Agency Grant [KC2015ZDYF0016A]; Guangdong Key Research Project [2014B090914003, 2015B090914002]; Guangdong Talents Project; National Basic Research Program of China [2015CB856505]; National Natural Science Foundation of China [51373075]; Guangdong Academician Workstation [2013B090400016]; Natural Science Foundation of Guangdong Province [2014A030313800]; Santander Universities Research Mobility AwardSCI(E)äžćœç§ćŠćŒææ°æźćș(CSCD)ARTICLE163-766
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