Weak, Quiet Magnetic Fields Seen in the Venus Atmosphere.

The existence of a strong internal magnetic field allows probing of the interior through both long term changes of and short period fluctuations in that magnetic field. Venus, while Earth's twin in many ways, lacks such a strong intrinsic magnetic field, but perhaps short period fluctuations can still be used to probe the electrical conductivity of the interior. Toward the end of the Venus Express mission, an aerobraking campaign took the spacecraft below the ionosphere into the very weakly electrically conducting atmosphere. As the spacecraft descended from 150 to 140 km altitude, the magnetic field became weaker on average and less noisy. Below 140 km, the median field strength became steady but the short period fluctuations continued to weaken. The weakness of the fluctuations indicates they might not be useful for electromagnetic sounding of the atmosphere from a high altitude platform such as a plane or balloon, but possibly could be attempted on a lander

Genetic analysis of common factors underlying cardiovascular disease-related traits

BACKGROUND: Cardiovascular disease-related traits, such as body mass index (BMI), systolic blood pressure (SBP), triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL), and glucose levels (GLUC), have moderate to high correlations with each other. We hypothesized that there might be some common factors underlying the correlations of these traits, and attempted to identify these factors and their genetic structures. Cross-sectional measurements from the 330 extended Framingham Heart Study families were used in this study. Principal component factor analysis was applied to obtain the factors that were then analyzed using variance components linkage analysis. RESULTS: With the above six traits three factors were generated: BMI-SBP-GLUC, HDL-TG, and TC-TG. The heritabilities for these factors were 32%, 45%, and 49%, respectively. Comparing the linkage results of the factors with the results of their component traits, evidence for linkage was observed for the TC-TG factor to a locus on chromosome 2p23 with a two-point LOD score 2.73 (marker GATA8F07) and a multipoint LOD score 1.81 (at 54 cM), while the LOD scores for TC and TG did not exceed 1 at this region. CONCLUSION: Our analysis showed a locus on chromosome 2 might have a pleiotropic effect on the cardiovascular disease-related traits TC and TG

Decentralized Estimation over Orthogonal Multiple-access Fading Channels in Wireless Sensor Networks - Optimal and Suboptimal Estimators

Optimal and suboptimal decentralized estimators in wireless sensor networks (WSNs) over orthogonal multiple-access fading channels are studied in this paper. Considering multiple-bit quantization before digital transmission, we develop maximum likelihood estimators (MLEs) with both known and unknown channel state information (CSI). When training symbols are available, we derive a MLE that is a special case of the MLE with unknown CSI. It implicitly uses the training symbols to estimate the channel coefficients and exploits the estimated CSI in an optimal way. To reduce the computational complexity, we propose suboptimal estimators. These estimators exploit both signal and data level redundant information to improve the estimation performance. The proposed MLEs reduce to traditional fusion based or diversity based estimators when communications or observations are perfect. By introducing a general message function, the proposed estimators can be applied when various analog or digital transmission schemes are used. The simulations show that the estimators using digital communications with multiple-bit quantization outperform the estimator using analog-and-forwarding transmission in fading channels. When considering the total bandwidth and energy constraints, the MLE using multiple-bit quantization is superior to that using binary quantization at medium and high observation signal-to-noise ratio levels

Analysis of transient overvoltage in 220 kV saturated core HTS FCL

Saturated Core High Temperature Superconducting (HTS) Fault Current Limiter (FCL) is one kind of limiters that can work effectively on short-circuit current limitation. In this paper, an equivalent circuit model depending on ac coil of HTS FCL is built for voltage distribution analysis under transient overvoltage. The equivalent circuit components, such as the capacitances and inductances, are calculated by using finite element method. The voltage distribution and oscillation analysis of ac coil may benefit to the insulation design of HTS FCL. © 2011 IEEE

The Search for Higher TcT_c in Houston

It is a great pleasure to be invited to join the chorus on this auspicious occasion to celebrate Professor K. Alex Mueller's 90th birthday by Professors Annette Bussman-Holder, Hugo Keller, and Antonio Bianconi. As a student in high temperature superconductivity, I am forever grateful to Professor Alex Mueller and Dr. Georg Bednorz "for their important breakthrough in the discovery of superconductivity in the ceramic materials" in 1986 as described in the citation of their 1987 Nobel Prize in Physics. It is this breakthrough discovery that has ushered in the explosion of research activities in high temperature superconductivity (HTS) and has provided immense excitement in HTS science and technology in the ensuing decades till now. Alex has not been resting on his laurels and has continued to search for the origin of the unusual high temperature superconductivity in cuprates.Comment: Dedicated to Alex Mueller, whose "important breakthrough in the discovery of superconductivity in ceramic materials" in 1986 has changed the world of superconductivit

Taxonomic studies of parasitic nyctotherans from chinese Anura amphibians IV. Spirocytopharynxa gen. nov and Macrocytopharynxa gen. nov.

Lian-Xiang U, Jian-Guo Wang and Wu-Han Xiao (2002) Taxonomic studies of parasitic nyctotherans from Chinese Anura amphibians IV. Spirocytopharynxa gen. nov. and Macrocytopharynxa gen. nov. Zoological Studies 41(1): 77-84. This paper describes 2 new genera and 5 new species of nyctotherans from Anura amphibians distributed in southern China. Based on the composition of the upper and bottom flaps, the number and position of sutural lines, the length of the oral groove, and the morphology and position of the end of the cytopharynx, the adoral zone of the membranelle (AZM), and the macronucleus, two new genera were established. The 3 new species, Spirocytopharynxa sinensis, S. guangxiensis, and S. quadranus, belong to the new genus Spirocytopharynxa, Another 2 species, Macrocytopharynxa (Nyctotheroidae Nie, 1932) pyriformis n. comb. and M. lingchuanensis n. sp., belong to the new genus Macrocytopharynxa. The characteristics for diagnosis of the 2 new genera and 5 new species are described in this paper

Study on Microcystis aeruginosa growth in incubator experiments by combination of Logistic and Monod functions

A combination of Logistic and Monod functions was proposed in this paper to study Microcystis aeruginosa growth in incubator experiments. This enables the Microcystis aeruginosa growth dynamics to be better described in incubator experiments and its parameters to be calculated more accurately. This method was justified by the data from the experiment and applied to study the effect of prometryn on Microcystis aeruginosa growth. In the experiment, a different concentrations of prometryn (0, 50, 100 and 200 μg·L−1) were added to the culture medium; the algal cell density, concentrations of orthophosphate (PO43−-P) and ammonia nitrogen (NH4+-N) were measured. The results show that Microcystis aeruginosa growth with time can be well described using the Logistic function. The maximum algae densities of Microcystis aeruginosa corresponding to the four prometryn concentrations are 11.7 × 106, 8.1 × 106, 5.6 × 106and 3.0 × 106cells·mL−1, respectively. The derived formula for the specific growth rate, growth rate and inhibition rate using Logistic function agreed reasonably well with the measured data. It was found that variations of consumed nutrients concentrations (PO43−-P and NH4+-N) can also be well described by the Logistic function. A function that describes the relationship between algal densities and consumed nutrient (PO43−-P and NH4+-N) concentrations is also derived from the Logistic function. Combination of Monod and Logistic functions can better describe relationship between specific growth rates and nutrients concentrations compared to the use of Monod function alone. In general, the half saturation coefficient, Kcfor PO43−-P (4.74 × 10−4, 1.99 × 10−3, 5.54 × 10−3and 3.87 × 10−2mg·L−1) and Kcfor NH4+-N (1.80 × 10−3, 5.84 × 10−3, 5.23 × 10−3and 1.06 × 10−2mg·L−1) in Monod function increase with increasing prometryn concentrations, which indicates that the affinity of algae growth to PO43−-P and NH4+-N decrease with increasing prometryn concentrations. In addition, relationships between nutrients concentrations and time can be derived by combining of Monod and Logistic functions, which agree well with the measured data. It is concluded that the combined application of Monod and Logistic functions provides a promising and more robust method of studying algal growth in incubator experiments

Characterization of High-Fat, Diet-Induced, Non-alcoholic Steatohepatitis with Fibrosis in Rats

An ideal animal model is necessary for a clear understanding of the etiology, pathogenesis, and mechanisms of human non-alcoholic steatohepatitis (NASH) and for facilitating the design of effective therapy for this condition. We aimed to establish a rat model of NASH with fibrosis by using a high-fat diet (HFD). Male Sprague–Dawley (SD) rats were fed a HFD consisting of 88 g normal diet, 10 g lard oil, and 2 g cholesterol. Control rats were fed normal diet. Rats were killed at 4, 8, 12, 16, 24, 36, and 48 weeks after HFD exposure. Body weight, liver weight, and epididymal fat weight were measured. Serum levels of fasting glucose, triglyceride, cholesterol, alanine aminotransferase (ALT), free fatty acids (FFA), insulin, and tumor necrosis factor-alpha (TNF-α) were determined. Hepatic histology was examined by H&E stain. Hepatic fibrosis was assessed by VG stain and immunohistochemical staining for transforming growth factor beta 1 (TGF-β1), and alpha-smooth-muscle actin (α-SMA). The liver weight and liver index increased from week 4, when hepatic steatosis was also observed. By week 8, the body weight and epididymal fat weight started increasing, which was associated with increased serum levels of FFA, cholesterol, and TNF-α, as well as development of simple fatty liver. The serum ALT level increased from week 12. Steatohepatitis occurred from weeks 12 through 48. Apparent hepatic perisinosodial fibrosis did not occur until week 24, and progressed from week 36 to 48 with insulin resistance. Therefore, this novel model may be potentially useful in NASH study

Prevention of Ichthyophthirius multifiliis infestation in goldfish (Carassius auratus) by potassium ferrate(VI) treatment

Ichthyophthirius multifiliis is an important freshwater teleost pathogen that often leads to significant economic losses to the aquaculture industry. The purpose of this study was to assess the acute toxicity of potassium ferrate(VI) to I. multifiliis theront and the concentration needed to prevent I. multifiliis infestation in goldfish, Carassius auratus. Five hundred theronts were exposed to concentrations of potassium ferrate(VI) in each well of a 96-well microtiter plate and observed for 4 h to determine the acute toxicity. Results showed that the exposure of I. multifiliis theronts to potassium ferrate(VI) at concentrations of 4.80 mg/L or more resulted in 100% mortality by 4 h; the LC50 value was estimated to be 1.71 mg/L Aqueous static renewal 96-h bioassays were carried out to determine the acute toxicity of potassium ferrate(VI) to goldfish. The LC50 value for potassium ferrate(VI) in goldfish was 42.51 mg/L. Goldfish were exposed to 4000 theronts/fish in aerated tap water (a dose previously shown to result in consistent infestation) and treated with a single dose of potassium ferrate(VI) after 30 min contact with theronts. Infection level and prevalence were recorded everyday after exposure. The results revealed that potassium ferrate(VI) at the 4.80 mg/L or more concentrations can significantly reduce not only the number of trophonts on the fin of goldfish on day 3 (P < 0.05), but also the prevalence of ichthyophthiriasis (P<0.05). Potassium ferrate(VI) at a concentration of 4.80 mg/L was considered to be the lowest effective dose to prevent infestation of I. multifillis in goldfish. (C) 2009 Published by Elsevier B.V

Quantum teleportation using active feed-forward between two Canary Islands

Quantum teleportation [1] is a quintessential prerequisite of many quantum information processing protocols [2-4]. By using quantum teleportation, one can circumvent the no-cloning theorem [5] and faithfully transfer unknown quantum states to a party whose location is even unknown over arbitrary distances. Ever since the first experimental demonstrations of quantum teleportation of independent qubits [6] and of squeezed states [7], researchers have progressively extended the communication distance in teleportation, usually without active feed-forward of the classical Bell-state measurement result which is an essential ingredient in future applications such as communication between quantum computers. Here we report the first long-distance quantum teleportation experiment with active feed-forward in real time. The experiment employed two optical links, quantum and classical, over 143 km free space between the two Canary Islands of La Palma and Tenerife. To achieve this, the experiment had to employ novel techniques such as a frequency-uncorrelated polarization-entangled photon pair source, ultra-low-noise single-photon detectors, and entanglement-assisted clock synchronization. The average teleported state fidelity was well beyond the classical limit of 2/3. Furthermore, we confirmed the quality of the quantum teleportation procedure (without feed-forward) by complete quantum process tomography. Our experiment confirms the maturity and applicability of the involved technologies in real-world scenarios, and is a milestone towards future satellite-based quantum teleportation