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Advances have been achieved in hyperspectral unmixing using the existing manifold Non‐negative Matrix Factorisation methods, although most of these methods only exploit the preliminary structural information, that is, the nearest neighbour graph. Consequently, the performance of these methods would be degraded when considering only the geometrical structure due to the diverse distribution of the hyperspectral data, that is, the close pixels could belong to different categories or the distant points could be sampled from the same classes. In this context, the present study worked from the perspective of both global and local data relationships to develop and propose a novel approach—the Global centralised and Structured discriminative Non‐negative Matrix Factorisation (GSNMF)—to achieve a further effective representation of hyperspectral unmixing. GSNMF involved maintaining the global centralised clustering and the local structured discriminative regularisation, based on which it could perfectly mine the structure information and drive a discriminative representation of the data. Experiments comparing the application of GSNMF and the state‐of‐the‐art methods to synthetic data demonstrated the superiority of GSNMF. In addition, the consistency of the fractional abundances obtained using GSNMF with the real distributions of spectral data was evaluated on two real‐world datasets. [ABSTRACT FROM AUTHOR]

This communication presents the design, fabrication, and full experimental verification of a frequency-controlled beam-steering antenna array with large scanning angle and low sidelobe. A brick configuration, which allows full 2-D beam-steering expansion, is implemented for the overall design and specifically optimized for further integration of corresponding transmitter/receiver (T/R) modules. A novel stripline-fed quasi-Yagi antenna constructed in a three-layer geometry is proposed as the radiation element. Moreover, a novel low insertion loss coplanar waveguide (CPW)-to-stripline transition, sheltered by ground in both sides, is proposed for the feeding and resistance loading. In this proposed antenna design, by applying a broadside coupling and optimizing the radiation element, a strong coupling is achieved at the center working frequency and can also maintain almost unchanged within the whole operational frequency range, leading to constant low sidelobe levels (SLLs). Three substrate layers are utilized to ensure accurate alignment between the slow-wave stripline and radiation elements, which is essential for the prevention of sidelobe deterioration due to possible fabrication tolerance. A 20 element prototype is demonstrated and manufactured. In the measurement, this antenna is able to scan from −42° to 36° within its 2 GHz operational bandwidth. Meanwhile, a flat gain around 15 dBi and a SLL smaller than −18.5 dB are obtained. The above performance indicates that this antenna is a good candidate for scaling to 2-D beam-scanning large array applications. [ABSTRACT FROM AUTHOR]

This paper presents a model predictive control (MPC) strategy for electric spring (ES) to address the power quality problems, especially voltage regulation and harmonic suppression, which are more acute for a growing proportion of renewable energy generation to the grid. A Kalman filter is used to estimate the random variation of the supply voltage and extract the fundamental and harmonic components of the supply voltage, respectively. In this way, the supply voltage, which is treated as an external disturbance for the plant, can be established in the state-space model form. Such processing brings great convenience to the application of MPC and also lays a foundation for MPC to achieve an ideal control effect. Based on an integrated state-space model of the supply voltage and the ES, an MPC controller is designed for power quality improvement. Simulation studies are carried out and the simulation results are presented to verify the effectiveness and accuracy of the control strategy. [ABSTRACT FROM AUTHOR]

Background: The American Heart Association released 7 modifiable factors, Life’s Simple 7, that are expected to improve cardiovascular health (CVH), but their contributions to ischemic heart disease (IHD) in the general Australians are not well clarified. Methods: We performed a cross-sectional study based on 7499 adults (≥18 years) who have tested for total cholesterol and fasting plasma glucose as part of 2011–12 Australian Health Survey. Poisson regression analyses were used to estimate the incidence rate ratios and population attributable fractions of those factors to IHD prevalence. Participants were classified into three CVH groups based on the number of ideal metrics: inadequate (0–2), average (3–4), and optimal (5–7). Logistic regression analyses were performed to elucidate the relationship between overall CVH and IHD prevalence. Results: 357 participants were self-reported having IHD condition, with a weighted prevalence of 3.3%. Physical inactivity, elevated body mass index (BMI) and total cholesterol (TC) were independently associated with IHD. Compared to the inadequate category, participants in the optimal and average categories have a 78% [adjusted odds ratio (OR), 0.22; 95% confidence interval (CI), 0.03–1.96] and a 45% (adjusted OR, 0.55; 95% CI, 0.39–0.77) lower IHD risk. One more optimal metric was associated with an 18% lower IHD risk (adjusted OR, 0.82; 95% CI, 0.71–0.93). Conclusions: Our findings indicate that physical inactivity, raised BMI and elevated TC were independent modifiable risk factors of IHD in the general Australian population. The improvement of overall CVH may also reduce IHD risk among the general Australian adults. [ABSTRACT FROM AUTHOR]

To optimize the artificial rumen microorganism sources and develop a stable artificial rumen system, batch and continuous operation were investigated with corn straw and food waste as substrates. The batch trials evaluated the volatile fatty acid (VFA) yield, biogas production, and lignocellulose degradation efficiency. The continuous test evaluated the performance of the artificial cow and sheep rumen systems using a dynamic membrane bioreactor (DMBR) with a stepwise organic loading rate at mesophilic temperature. The anaerobic digestion (AD) of the lignocellulose biomass after rumen fermentation pretreatment and of the permeate from the artificial rumen system were also evaluated for CH 4 production. The results indicated that the cow rumen microorganisms were more suitable than sheep rumen microorganisms for lignocellulosic biomass pretreatment and maximized the CH 4 yield through the AD process without inhibition. After approximately four months of continuous operation, a stable and continuous artificial rumen system for lignocellulosic biomass degradation was achieved with cow rumen fluid as inoculum. Based on analysis of the core lignocellulose-degrading enzyme levels and gel filtration chromatography, the cow rumen microorganisms could secrete more extracellular multienzyme complexes to hydrolyze lignocellulosic biomass than the sheep rumen microorganisms in vitro. During the batch and continuous operations, a high diversity and similar richness of bacteria and fungi demonstrated that the cow rumen microorganisms can be used as a preferred inoculum for the artificial rumen system. The use of an artificial cow rumen system with a DMBR is a promising way to construct a stable and continuous artificial rumen system to biodegrade lignocellulosic biomass for biogas production. Unlabelled Image • Rumen fermentation enhanced the AD efficiency of corn straw and food waste. • Stable and continuous operation of artificial rumen system in a DMBR was conducted. • Artificial cow rumen system is a promising way to degrade lignocellulosic biomass. • Artificial cow/sheep rumen fermentation compared in batch and continuous operations. [ABSTRACT FROM AUTHOR]

To enhance the degradation of wheat straw (WS) and corn straw (CS) in rumen fermentation, characterization of degradation and ruminal microorganisms of monosubstrate (WS/CS) groups and a cosubstrate strategy with food waste (FW) group was performed. The cellulose, hemicellulose, and lignin degradation efficiency of WS and CS; soluble chemical oxygen demand; volatile fatty acid yields; and activity of ligninolytic, cellulolytic, and hemicellulolytic enzymes for the cosubstrate group were improved compared with those for the corresponding monosubstrate groups. An accurate and a good of fit of the Weibull kinetic model, decreased crystallinity index values, and characteristic absorbance bands in the Fourier transform-infrared spectra further confirmed that cosubstrate addition with FW decreased the resistance of cellulose and hemicellulose to biodegradation. High-throughput sequencing results suggested that the bacterial diversity in CS rumen fermentation and fungal diversity and richness in WS rumen fermentation were promoted with FW as a cosubstrate. The cosubstrate addition with FW significantly affected the composition of the ruminal bacteria and fungi in rumen fermentation. The relative abundances (RAs) of rumen bacteria were increased in the cosubstrate CS/WS and FW fermentation conditions, and the enhancement of CS degradation with FW supplementation was stronger than that of WS rumen fermentation with FW supplementation. The RAs of the ruminal fungal genera Ustilago and Fusarium were promoted in CS and WS fermentation with FW, respectively. Moreover, the fermentation properties and rumen flora in the FW rumen fermentation also provided some evidence to suggest an enhancement of the cosubstrate strategy compared with the monosubstrate strategy. Image 1 • Food waste (FW) increased alkalinity and improved VFAs yield in rumen fermentation. • Wheat/corn straw (WS/CS) rumen degradation was enhanced by cosubstrate with FW. • Lignocellulases and bacterial diversity in CS and FW fermentation were improved. • Fungal diversity and richness in WS fermentation were promoted with FW addition. [ABSTRACT FROM AUTHOR]

The performance and stability of mesophilic codigestion of waste activated sludge (WAS) and food waste (FW) were compared in two parallel, continuously stirred tank reactors using high- and low-magnitude loading increments for the loading regimes. The results indicated that a high methane (CH 4) production of 6.98 L L−1·d−1 was realized without volatile fatty acid accumulation via low-magnitude loading increments at a high loading of 26.5 g-COD·L−1·d−1, and this system was more stable and achieved a higher efficiency than the codigestion system that used high-magnitude loading increments at similar loading and operating conditions. Furthermore, higher CH 4 yields of 258–334 mL-CH 4 ·g-COD−1, TCOD removal efficiencies of 64–79%, conversion ratios of 62–88%, and methanogenic activities of 0.37–0.40 g-CH 4 -COD·g-VS−1·d−1 were consistently maintained via the low-magnitude loading increments during the high-rate period. High abundances of the phyla Firmicutes (63.3%) and genus Methanosarcina (94.5%) contributed to the high rates and stable operating conditions of the mesophilic system for WAS and FW codigestion using low-magnitude loading increments. [Display omitted] • Two CSTR codigestion systems with different incremental loadings were compared. • Low-magnitude loading increments can lead to stable and high rates of codigestion. • A high abundance of Methanosarcina was induced via low-magnitude loading increments. • Low-magnitude loading increments provides an easy-to-apply and promising approach. [ABSTRACT FROM AUTHOR]

Rumen fermentation is known to be effective for lignocellulosic-wastes biodegradation to certain extent but it is still unclear if there exists a termination of the microorganisms' action to further degrade the bio-refractory fractions. In order to illuminate the related microbiological characteristics, experiments were conducted in a prolonged duration of rumen fermentation of mechanically ruptured wheat straw, with inoculation of cow rumen microorganisms in vitro. Although the organic wastes could not be biodegraded quickly, continuous conversion of the lignocellulosic contents to volatile fatty acids and biogas proceeded in the duration of more than three months, resulting in 96–97% cellulose and hemicellulose decomposition, and 42% lignin decomposition. X-ray diffraction and Fourier transform infrared spectroscopy further demonstrated the characteristics of lignocellulosic structure decomposition. Under the actions of cow rumen microorganisms, stable pH was maintained in the fermentation liquid, along with a steady NH 4 +-N, volatile fatty acids accumulation, and a large buffering ability. It was identified by enzyme analysis and Illumina MiSeq sequencing that the rich core lignocellulolytic enzymes secreted by the abundant and diverse rumen bacteria and fungi contributed to the persistent degradation of lignocellulosic wastes. Members of the Clostridiales order and Basidiomycota phylum were found to be the dominant lignocellulolytic bacteria and fungi, respectively. It could thus be inferred that the main lignocellulose degradation processes were a series of catalytic reactions under the actions of lignocellulolytic enzymes secreted from bacteria and fungi. The dominant hydrogenotrophic methanogens (Methanomassiliicoccus , Methanobrevibacter , Methanosphaera , and Methanoculleus) in the rumen could also assist CH 4 production if the rumen fermentation was followed with anaerobic digestion. Unlabelled Image • High WS decomposition was achieved by the persistent action of cow rumen microflora. • Degradation characteristics of raw WS subject to rumen fermentation were analysed. • Rich core lignocellulolytic enzymes were secreted by the rumen bacteria and fungi. • Firmicutes and Basidiomycota were the dominant lignocellulolytic bacteria and fungi. • Degradation mechanisms for the in vitro rumen fermentation of WS were elucidated. [ABSTRACT FROM AUTHOR]

Background: Polycystic ovary syndrome (PCOS) is characterized by hyperandrogenism, hyperinsulinemia, and infertility. In PCOS, abnormal regulation of relevant genes is required for follicular development. By binding to the 3' untranslated region (3'URT), microRNAs (miRNAs) are widely involved in posttranscriptional gene regulation. However, few studies have been conducted on circulating miRNA expression in PCOS. This study aims to describe altered expression of circulating miR-21 in PCOS., Methods: The expression of serum miRNAs of PCOS patients were explored using the TaqMan Low Density Array followed by individual quantitative reverse transcription polymerase chain reaction assays. The protein level of LATS1 was determined using Western blot. To validate whether miR-21 targeted LATS1, the luciferase assay was applied., Results: In comparison with normal subjects, the circulating level of miRNA-21 was significantly enhanced in PCOS patients. In PCOS patients, the expression levels of MST1/2, LATS1/2, TAZ were much lower than the control subjects. Luciferase reporter assay revealed that LATS1 was a downstream target of miR-21., Conclusions: In comparison with normal subjects, serum miR-21 is obviously increased in PCOS patients. Through targeting LATS1, miR-21 could prompt PCOS progression and could act as a novel non-invasive biomarker for diagnosis of PCOS.