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The availability of phosphorus (P) fertilizer applied to soil can diminish rapidly because of the complex soil P immobilization processes. However, the quantitative distribution of fertilizer P in the soil P fractions is not fully understood. Here, two experiments were conducted in a greenhouse using 32P‐labelled KH2PO4 to (i) quantify the distribution of P fertilizer in soil fractions, microorganisms and maize shoots grown in contrasting soils; (ii) characterize the effect of planting maize on soil P fractions and (iii) determine the amount of plant P derived from fertilizer vs. soil. Depending on the soil type, 74.1%–84.1% of the labelled P was retained in the soil, 11.4%–14.5% was found in maize shoots and 0.7%–4.5% was present in microorganisms. Distribution of applied P in the soil P fractions was dependent on soil type, with most P present as NaOH‐Pi and residual‐P in the Red soil, and as HCl‐P in the Fluvo‐aquic soil. Root‐mediated processes were involved in mobilisation of residual‐P in all three soils, with significant depletion of NaOH‐Pi in the Red soil, NaOH‐Pi and HCl‐P in the Black soil, and HCl‐P in the Fluvo‐aquic soil. The plant P derived from fertilizer and soil increased with increasing P addition rates in all three soils. In the soils with low‐P availability, fertilizer contributed more P to plants than soil, whereas in the initially high‐P soil, the opposite occurred. In conclusion, the partitioning of fertilizer P to various soil P fractions is dependent on the soil type, and the contribution of P derived from fertilizer to maize P uptake was related inversely to the soil legacy P. [ABSTRACT FROM AUTHOR]

Torreya grandis is a unique tree species in China. Although full use has been made of the timber, the processing and utilization of the bark has not been effective. In order to explore a new way to utilize the bark of Torreya grandis , a powder of T. grandis bark was prepared and analyzed qualitatively and quantitatively. Differential scanning calorimetry (TG) and pyrolysis gas chromatography-mass spectrometry (PY-GC/MS) revealed many bioactive components in the bark of T. grandis, such as acetic acid, 2-methoxy-4-vinyl phenol, D-mannose, and furfural. These substances have potential broad applications in the chemical industry, biomedicine, and food additives. The chemical constituents of the bark of T. grandis suggest a theoretical basis for the future development and utilization of the bark of T. grandis. [ABSTRACT FROM AUTHOR]

The growing preponderance of light emitting diodes (LEDs) for lighting has motivated research into their dual use for visible light communication (VLC) and navigation. VLC extracts a bit sequence from a series of photodetector scans. Among this data is an LED ID that ensures the reliable data association in navigation and data communication. Recovering the LED data and ID requires the accurate prediction of each LED’s projected position on the photodetector array to extract efficiently and reliably the LED ON–OFF status in each photodetector scan. Estimating the LED projected position is challenging because: 1) clutter and noise corrupt the measurements; 2) the LED status will be OFF in some scans; and 3) the predicted projection location sequence depends on the estimated rover state trajectory, which is uncertain and time varying. This paper presents a method to determine the $q$ -most probable data and the LED position sequences simultaneously for a time window of data, using Bayesian multiple hypothesis tracking techniques by maximizing the posterior probabilities. This paper focuses on the VLC data and the LED position sequence extraction, which includes rover state estimation. Implementation of the multiple hypothesis tracking algorithm is illustrated by postprocessed experimental results. [ABSTRACT FROM PUBLISHER]

Atractylenolides compounds (atractylenolide-I, atractylenolide- II and atractylenolide- III) extracted from Atractylenolides macrocephala were analysed for their differential presence in the rhizome of both the infected and healthy plants and its fungitoxicity on prophylactic treatment with polysaccharides of Chrysanthemum indicum against Sclerotium rolfsii. It was evident that the plant under stress by pathogen has instigated the significant synthesis and accumulation of atractylenolide- II and atractylenolide- III in the rhizome of plants as a result of elicitation with polysaccharides of C. indicum. Our results also showed that the absence of atractylenolide- II in the rhizome made the plant susceptible to S. rolfsii. Furthermore, on in vitro antifungal studies, exogenous application of atractylenolide- II with the concentration of 200 μg/ml showed a significant inhibitory effect on mycelial growth by achieving a 77.23% antifungal activity rate, and a minimal inhibitory effect at a concentration of 12.5 μg/ml with atractylenolide- II. To our knowledge, this novel study on phytoalexins in A. macrocephala suggested that A. macrocephala plants produce elevated levels of atractylenolide- II and atractylenolide- III in a pattern typical of phytoalexins, in response to an eliciting treatment after infection. [ABSTRACT FROM AUTHOR]

Inertial navigation systems for underwater vehicles are often aided by acoustic time-of-flight positioning schemes. One widely implemented long baseline (LBL) approach uses a ping-response protocol resulting in asynchronous measurements that depend on the state of the vehicle at two time instants. Such aiding measurements that depend on the state at multiple time instants do not fit the model format of the standard extended Kalman filter (EKF) framework. This paper proposes a near-real-time (NRT) Bayesian smoothing framework for the LBL-aided inertial navigation system application. Within this NRT framework, the time interval between LBL cycles is divided into two intervals defined by the ping-response cycles of LBL. The time instant when all the LBL responses are received will be referred to as the NRT point. Between the LBL ping and the NRT point, a traditional real-time EKF is implemented using the inertial measurement unit and all aiding measurements. After the NRT point, when all the LBL responses have been received, an optimal Bayesian trajectory estimator executes. This maximum a posteriori (MAP) estimation includes all the measurement information already collected up to the NRT point of the current LBL cycle. The MAP output is a smoothed trajectory estimate for the period of time between the LBL ping and the NRT point. At the conclusion of this smoothing process, the current EKF estimate is corrected to the optimal MAP solution and propagated to the current time, and then the EKF estimation process continues to the NRT point of the next LBL cycle. At all times, the approach maintains a real-time state estimate suitable for use by the control system. This paper presents the theoretical solution, discusses the implementation, and presents implementation results to illustrate the accuracy and reliability of this NRT approach. [ABSTRACT FROM PUBLISHER]

In the title compound, C19H23N3OS, the two fused rings of the thieno[2,3- d]pyrimidin-4(3 H)-one system are almost coplanar. The packing of the mol­ecules in the crystal structure is determined by van der Waals forces. No inter­molecular hydrogen-bonding inter­actions or π–π stacking inter­actions are present in the crystal structure. [ABSTRACT FROM AUTHOR]

Polysaccharides isolated from Chrysanthemum indicum were studied for their pathogen-derived resistance against Sclerotium rolfsii sacc in Atractylodis maceocephalae koidz . The total sugar content and monosaccharide analysis were determined by phenol–sulfuric acid method and gas chromatography, and infrared spectroscopy performed for simple structure information. The activities of CAT and POD as protective enzymes in A. maceocephalae leaves were evaluated. The purified polysaccharides exhibited strong CAT and POD activities in inoculated with S. rolfsii in A. macrocephala leaves, attained the maximum value 568.3 Ug −1 min −1 and 604.4 Ug −1 min −1 respectively. Whereas, when compared with the control plants, 20 mg/ml purified polysaccharides exhibited the strongest CAT and POD activities. Notably, the treatments of A. macepcephalae seedlings with C. indicum polysaccharides (CIP) decreased disease index development caused by S. rolfsii . The disease index after 10 days was significantly reduced when the seedlings treated with 20 mg/ml CIP, 4.41 compared to the control plants 32.00. Given together, these results indicated that purified polysaccharides derived from C. indicum may be useful as a natural inducer. [ABSTRACT FROM AUTHOR]