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Streptococcus thermophilus is one of the most valuable homo-fermentative lactic acid bacteria, which, for a long time, has been widely used as a starter for the production of fermented dairy products. The key production characteristics of S. thermophilus, for example the production of extracellular polysaccharide, proteolytic enzymes and flavor substances as well as acidifying capacity etc., have an important effect on the quality of dairy products. The acidification capacity of the strains determines the manufacturing time and quality of dairy products. It depends on the sugar utilization ability of strains. The production of extracellular polysaccharide is beneficial for improving the texture of dairy products. Flavor substances increase the acceptability of dairy products. The proteolytic activity of the strain influences not only the absorption of the nitrogen source, but also the formation of flavor substances. Different strains have obvious differences in production characteristics via long-time evolution and adaptation to environment. Gaining new strains with novel and desirable characteristics is an important long-term goal for researchers and the fermenting industry. The understanding of the potential molecular mechanisms behind important characteristics of different strains will promote the screening and breeding of excellent strains. In this paper, key technological and functional properties of different S. thermophilus strains are discussed, including sugar metabolism, proteolytic system and amino acid metabolism, and polysaccharide and flavor substance biosynthesis. At the same time, diversity of genomes and plasmids of S. thermophilus are presented. Advances in research on key production characteristics and molecular levels of S. thermophilus will increase understanding of molecular mechanisms of different strains with different important characteristics, and improve the industrialization control level for fermented foods. [ABSTRACT FROM AUTHOR]

α-Synuclein (α-syn) is an intrinsically disordered protein abundantly distributed in presynaptic terminals. Aggregation of α-syn into Lewy bodies (LB) is a molecular hallmark of Parkinson's disease (PD). α-Syn features an extreme conformational diversity, which adapts to different conditions and fulfills versatile functions. However, the molecular mechanism of α-syn transformation and the relation between different structural species and their functional and pathogenic roles in neuronal activities and PD remain unknown. In this mini-review, we summarize the recent discoveries of α-syn structures in the membrane-bound state, in cytosol, and in the amyloid state under physiological and pathological conditions. From the current knowledge on different structural species of α-syn, we intend to find a clue about its function and toxicity in normal neurons and under disease conditions, which could shed light on the PD pathogenesis. [ABSTRACT FROM AUTHOR]

Motivation: During the evolution, functional sites on the surface of the protein as well as the hydrophobic core maintaining the structural integrity are well-conserved. However, available protein structure alignment methods align protein structures based solely on the 3D geometric similarity, limiting their ability to detect functionally relevant correspondences between the residues of the proteins, especially for distantly related homologous proteins. Results: In this article, we propose a new protein pairwise structure alignment algorithm (UniAlign) that incorporates additional evolutionary information captured in the form of sequence similarity, sequence profiles and residue conservation. We define a per-residue score (UniScore) as a weighted sum of these and other features and develop an iterative optimization procedure to search for an alignment with the best overall UniScore. Our extensive experiments on CDD, HOMSTRAD and BAliBASE benchmark datasets show that UniAlign outperforms commonly used structure alignment methods. We further demonstrate UniAlign's ability to develop family-specific models to drastically improve the quality of the alignments. Availability and implementation: UniAlign is available as a web service at: http://sacan.biomed.drexel.edu/unialign [ABSTRACT FROM AUTHOR]

We present a new device, the diffractive optics calibrator, for measuring duty cycle and etching depth for computer-generated holograms (CGHs). The system scans the CGH with a collimated laser beam and collects the far-field diffraction pattern with a CCD array. The relative intensities of the various orders of diffraction are used to fit the phase shift from etching and the duty cycle of the binary pattern. The system is capable of measuring variations that cause 1-nm peak- to-valley (PV) phase errors in the wavefront created by the CGH. The measurements will be used primarily for quality control CGHs, but the data can also be used to provide a lookup table for corrections that allow calibration of the lithography errors. Such calibrations may be necessary for us to achieve our goal of measuring freeform aspheric surfaces with 1-nm RMS accuracy. [ABSTRACT FROM AUTHOR]

[Objectives] The study aimed to discuss the influence of light and temperature factors on biomass accumulation of winter wheat at each growth stage and changes in biomass of each organ. [Method] Based on the observation data from Xifeng Agrometeorological Experiment Station of Gansu Province, including phenophase and yield factors of winter wheat in 1981 -2008, biomass at three-leaves, overwintering, jointing, heading, milky maturity, and maturity stages in 1995 -2008, and meteorological data in 1995 -2008, the variation patterns of the biomass accumulation and the influence of TEP (thermal effectiveness photosynthetically active radiation) on the biomass of winter wheat at every growth stage were analyzed. [Result] The biomass accumulation of winter wheat in the whole growth period presented "5" curve, with the maximum value from heading to milky maturity stage. Since 1981, TEP from heading to milky maturity stage increased with a rate of 3. 314 MJ/( m2 · a), and the changing curves of TEP at other stages were like parable curves. TEP from turning green to jointing stage and from milky maturity to maturity stage had a higher value in the 1990s and a lower value in the 1980s and early 21st century, while that from jointing to heading stage had a lower value in the 1990s but a higher value in the 1980s and early 21st century. There was a significant correlation between TEP at each growth stage and the actual yield. LAI (leaf area index) at each development stage also had a significant correlation with the utilization rate of TEP at corresponding stage. When LAI at jointing and heading stages increased by 1, the utilization rate of TEP correspondingly increased by 0. 049 and 0.259 g/MJ respectively. [Conclusion] The research could provide theoretical references for the scientific planting and management of winter wheat in future. [ABSTRACT FROM AUTHOR]

A triple-stage signal processing technique is developed for harmonic and interharmonic estimations in power systems. Firstly, the fundamental period is evaluated accurately by the multi-rate narrow bandpass finite impulse response (FIR) filter and the zero-crossing method. The actual sampling sequence can then be reconstructed to a quasi-synchronous sampling one. Consequently, a comb FIR filter can be applied to separate harmonics and interharmonics. Secondly, interharmonics are evaluated by the windowed and interpolated fast Fourier transform method, of which, harmonic interference is eliminated from interharmonics by the comb FIR filter. Thirdly, harmonic parameters are determined directly from the discrete Fourier transform results after quasi-synchronization. Simulation results show that the present method has a high accuracy of measurement for harmonic and interharmonic estimations under the circumstances of noise interference. Finally, experimental results on a self-developed power quality analyzer have demonstrated the validity of both the algorithm and the simulation. [ABSTRACT FROM AUTHOR]

The transcutaneous energy transmission system (TETS) composed of a Class-E amplifier may operate at a state away from the optimum power transmission due to the load variation. By introducing the feedback-loop technique, the TETS can keep the optimum state with constant output voltage by adjusting the important design parameters, that is, the duty ratio and frequency of the driving signal and the supply voltage. The relations between these adjusted parameters and the load are investigated. The effectiveness of the feedback technique is validated through a design example with a variable load parameter. The experimental results show that the Class- E amplifier in the feedback loop can keep operating at the optimum state under the condition of up to 50 percent variation of the load value. [ABSTRACT FROM AUTHOR]

A novel switching-based filter is proposed to suppress the impulse noise and preserve the fine details in the color image. The filtering method is divided into two stages, the noise detection and the noise cancellation. In the first stage of noise detection, pixels with similar color components in many neighboring positions are counted to see whether the current pixel is corrupted by impulse noise. In the second stage of noise cancellation, the previous outputs and the detected noise-free pixels are chosen as the samples of the vector median filter operation to improve the performance on suppressing impulse noise. Several experimental results have demonstrated that the proposed filter outperforms many filters in terms of both noise suppression and detail preservation. [ABSTRACT FROM AUTHOR]

In order to find out hydrogen content change law in ESR ingot during electroslag remelting， and on the basis of each process optimize to improve the electric slag ingot hydrogen content qualified rate ， nuclear power steel 316H is taken as the research object to study processing parameters such as melting speed， filling ratio， slag ingredients， amount of slag added， initial hydrogen of electrode and partial pressure of water vapor by using a 15 ton electroslag furnace in this paper.The results show that hydrogen addition is different in each stage of electroslag remelting，the hydrogen content in ESR ingot is proportional to the square root of water pressure in the air. The CaO can promote hydrogen increase and MgO can prevent hydrogen increase in the slag ingredients. Increasing the melting rate， reducing the amount of slag， increasing the filling ratio and improving the cleanliness of the electrode surface are beneficial to prevent hydrogen of electroslag ingot increase. When the initial hydrogen of the electrode is less than 2×10-6， the hydrogen absorption of the remelting process of the electroslag is more serious. When the initial hydrogen of the electrode is in the range of 2×10-6-4×10-6， the hydrogen absorption of the electroslag remelting process becomes weaker. When the initial hydrogen of the electrode is greater than 4×10-6， the electroslag remelting process will appear dehydrogenation.After the process optimization， the average qualified rate of hydrogen reaches 97.5%， which is 2.8% higher than 94.7% before the optimization.

A novel Kevlar/STG (Kevlar fabrics immersed with shear thickening gel) fabrics composite with high anti-impact performance was fabricated. By utilizing a unique multi-sensor force testing system, both low- and high-velocity impact experiments were conducted to investigate the anti-impact performance of Kevlar/STG fabrics. In low-velocity testing, the attenuation of the impact center force for Kevlar/STG was 64.1%, which was much larger than the Kevlar (27.0%). Under high-velocity loading, the impact force of Kevlar/STG attenuated from 805 N to 223 N with the increase of layers from 5-layers to 20-layers, while they reduced from 1125 N to 460 N for Kevlar fabrics. Meanwhile, the failure mode was analyzed and it was found that the high anti-impact performance was originated from the shear thickening effect and enhanced friction. In consideration of the good flexibility and excellent safe guarding property, the Kevlar/STG showed promising perspective in body armor. [ABSTRACT FROM AUTHOR]

As an environmental energy, air-borne sound can be harvested for the long-term local energy supply of wireless sensors and portable devices. A compact acoustic energy harvesting (AEH) system is proposed, which consists of a beam-based PZT transducer and a dual-layer of acoustic metamaterial denoted as the layered acoustic metamaterial (LAM). The pressure amplification effect inside LAM can substantially increase motions of the PZT transducer. Therefore, in order to effectively improve the electromechanical conversion efficiency, the first bending mode of the PZT transducer is designed to generate the resonating vibration at the frequency related to the pressure amplification effect. An impedance-based theoretical model is developed to investigate the conditions for maximizing the pressure amplification effect. Experimental results show that the LAM sample in the proposed AEH system enhances the sound pressure level by 18 dB at 318 Hz. Under the condition of the incident sound pressure level of 100 dB, the maximum open-circuit output voltage of the proposed system reaches 72.6 mV, which is 4.2 times greater than that of the same PZT transducer without LAM. [ABSTRACT FROM AUTHOR]

The article focuses on endovascular middle cerebral arterial occlusion in a chronic cerebral ischemia model. For this study, endovascular intervention was used in order to establish cerebral infarction models in rhesus monkeys. Pronounced paralysis at the acute phase and long-term upper extremity dysfunction at the chronic phase were observed. This study found that there is a high animal survival rate in stroke models of middle cerebral artery upper trunk occlusion.

A novel filter is proposed in this work to remove noise and preserve fine details from the impulse-corrupted images based on median and partition operation. Each pixel is classified into one of the mutually exclusive partition blocks by a novel observation vector. This observation vector can be directly used to partition the observation space without using predefined thresholds. The weight of each block is obtained using a learning approach based on the least-mean-square algorithm. The noise-filtering process is progressively applied through several iterations to achieve better noise-suppression results. Several experimental results have demonstrated that the proposed filter outperforms many filters in terms of both noise suppression and detail preservation. [ABSTRACT FROM AUTHOR]

Precise manufacturing of optical flats requires precise characterization of the surface. A scanning pentaprism system is ideal for use as an absolute and precise test for an optical flat. Such a system was built and used to test a 2-m diameter flat mirror. This system uses light from an autocollimator that is reflected from two pentaprisms to project reference beams of light onto the flat mirror. The light reflected from the mirror back through the pentaprisms provides information on low order optical aberrations in the flat mirror. We report results of the test on a 2-m flat, characterizing the errors and their sources. There is enormous potential for our system to be used to test larger flats and even curved surfaces, made of either a glass or a liquid. [ABSTRACT FROM AUTHOR]

In the last larval instar, uncommitted progenitor cells in the Drosophila eye primordium start to adopt individual retinal cell fates, arrest their growth and proliferation, and initiate terminal differentiation into photoreceptor neurons and other retinal cell types. To explore the regulation of these processes, we have performed mRNA-Seq studies of the larval eye and antennal primordial at multiple developmental stages. A total of 10,893 fly genes were expressed during these stages and could be adaptively clustered into gene groups, some of whose expression increases or decreases in parallel with the cessation of proliferation and onset of differentiation. Using in situ hybridization of a sample of 98 genes to verify spatial and temporal expression patterns, we estimate that 534 genes or more are transcriptionally upregulated during retinal differentiation, and 1367 or more downregulated as progenitor cells differentiate. Each group of co-expressed genes is enriched for regulatory motifs recognized by co-expressed transcription factors, suggesting that they represent coherent transcriptional regulatory programs. Using available mutant strains, we describe novel roles for the transcription factors SoxNeuro (SoxN), H6-like homeobox (Hmx), CG10253, without children (woc), Structure specific recognition protein (Ssrp), and multisex combs (mxc). [ABSTRACT FROM AUTHOR]

Closed-loop control plays an important role in the treatment of epileptiform spikes by using brain stimulation. In recent years, there have been many analytical methods for determining stimulus protocols and stimulus parameters. However, the analytical method that can start the stimulus protocol when it is needed and stop the stimulus protocol when it is not needed is rather rare. In this work, we design an analytic closed-loop control scheme which can starts control when epileptiform spikes are detected and stops control when no epileptiform spikes are detected. The neural mass model is used to simulate the generation of normal Electroencephalograph signals and epileptiform spikes. The detection of epileptiform spikes is completed via an alarm threshold which is set by using the combination of cross approximate entropy, the Pearson correlation coefficient and the fuzzy theory. If the detection result shows that there are epileptiform spikes in the neural mass model, the fuzzy proportion integration differentiation control works so that the abnormal epileptiform spikes are restored to normal EEG signals, and vice versa. The simulation confirms the effectiveness of the proposed closed-loop control scheme.

Heat shock protein 104 (HSP104) is a conserved AAA+ protein disaggregase, can disassemble the toxic aggregates formed by different amyloid proteins, and is protective in various animal models associated with amyloid-related diseases. Extensive studies have attempted to elucidate how HSP104 disassembles the aggregated form of clients. Here, we found that HSP104 exhibits a potent holdase activity that does not require energy, prevents the soluble form of amyloid clients from aggregating, and differs from HSP104's disaggregase activity. Using cryo- EM, NMR, and additional biophysical approaches, we found that HSP104 utilizes its small subdomain of nucleotide-binding domain 2 (ssNBD2) to capture the soluble amyloid client (K19 of Tau) independent of its ATP hydrolysis activity. Our results indicate that HSP104 utilizes two fundamental distinct mechanisms to chaperone different forms of amyloid client and highlight the important yet previously unappreciated function of ssNBD2 in chaperoning amyloid client and thereby preventing pathological aggregation. [ABSTRACT FROM AUTHOR]