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As one of the most classical digital signal processing (DSP) techniques, the wavelet transformation (WT) has been applied to detect and classify power system disturbances for many years. However, its performance is easily affected by harmonics. This makes it difficult to detect and classify disturbances occurring in an islanded micro-grid, especially when nonlinear loads are involved. To improve the performance of WT, in this article, the Renyi entropy is used with WT to detect and classify seven types of disturbance. To demonstrate the efficacy of Renyi entropy in the wavelet domain, a comparison is made by detecting and classifying disturbances using the raw data with the time-domain-based Renyi entropy. Other comparisons are also performed to show how the performance of Renyi is affected by different order values of Renyi and the non-linear loading level. Detection and classification are made by using the support vector machine (SVM) and K-nearest neighbour (KNN) classifiers. The results demonstrate the effectiveness of WT-based Renyi entropy and show that the performance accuracy improves with the increase in the percentage of non-linear loads. [ABSTRACT FROM AUTHOR]

Plant roots can substantially improve slope stability and prevent soil slippage. Many researchers have quantified effects of root properties on soil reinforcement. However, the mechanism of root architecture on shear strength increments needed to be studied and analysed. This paper presents a man-made direct shear test to compare the effects of six tree species roots on soil reinforcement. Thus, root tensile strength, diameter, root area ratio (RAR), inclination and distribution were measured to study the differences between root architecture. Meanwhile, stress propagation simulations were conducted to analyse the mechanisms of root architecture on soil reinforcement. Results showed that shear strength increment value corresponded to P. massoniana (42.4 kPa), followed by C. camphora (37.6 kPa), N. aurata (36.0 kPa), L. kwangtungensis (28.8 kPa), G. acuminata (27.4 kPa) and S. laurina (23.0 kPa). Root architecture that contained taproots (VH-type) and widely distributed roots (H-type) showed larger shear strength increments than that contained oblique roots (R-type) when the initial friction between soil and root was ignored. When there are thick, widely distributed roots in the root system, the resistance of root architecture on shear failure would become larger. Root diameter class and RAR cannot be used to reflect the effects of root architecture on soil shear strength increment. While estimating the different tree species roots on soil reinforcement in field, initial friction between soil and root should be considered as important as root architecture. [ABSTRACT FROM AUTHOR]

The effects of plant roots on the increase in soil shear strength involve a complex interaction of mechanical and hydrological processes operating over a scale of very diverse root architecture. Understanding the effects of mechanical mechanisms on soil shear strength is challenged by this inherent complexity. A high level of inaccuracy in field measurements of soil reinforcement makes field measurements much more challenging than that of indoor observations. This paper presents a simple experimental study where the shear strength of undisturbed soil is measured at different soil depths and at different distances from the main stems of 7 tree species, a bamboo, a herbaceous perennial, perennial grass and a fern by measuring their root area ratio, diameter class, and tensile strength. The result confirms that root distribution varies widely within root diameter classes and root area ratio between species and soil layers. Root architecture characteristics were the dominant factors influencing shear strength in the 0.2-0.4 m soil layer. In the process of vegetation restoration, O. compositus and H. fulva were used as colonizing vegetation. Later, S. lucida and L. kwangtungensis were recommended to stabilize the shallow soil in the Three Gorges reservoir region. [ABSTRACT FROM AUTHOR]

Bromodomain PHD finger transcription factor (BPTF), a ubiquitously expressed ATP-dependent chromatin-remodeling factor, is critical for epigenetically regulating DNA accessibility and gene expression. Although BPTF is important for the development of thymocytes, its function in mature T cells remains largely unknown. By specifically deleting BPTF from late double-negative 3/ double-negative 4 stage of developing T cells, we found that BPTF was critical for the homeostasis of T cells via a cell-intrinsic manner. In addition, BPTF was essential for the maintenance and function of regulatory T (Treg) cells. Treg cell-specific BPTF deletion led to reduced Foxp3 expression, increased lymphocyte infiltration in the nonlymphoid organs, and a systemic autoimmune syndrome. These findings therefore reveal a vital role for BPTF in T and Treg cell function and immune homeostasis. [ABSTRACT FROM AUTHOR]

In an optical synthetic aperture imaging system, it is necessary to extract edge information of subapertures with complex shape and large gaps, aiming at cophasing of segmented mirrors ultimately. As a measure of image surface irregularities, fractal dimension (FD) was calculated for edge extraction and surface complexity evaluation. The modified differential box-counting (DBC) method was adopted to calculate FD, specifically the window merge replication method was presented to achieve FD estimation with a relatively small scanning window. The subaperture region and interference fringe edge were extracted by using a two-step strategy of preprocessing and postprocessing. Simulations and experiments are conducted to verify the feasibility and accuracy for edge extraction. As well, the capabilities of the proposed method are demonstrated with the results of numerical calculation. [ABSTRACT FROM AUTHOR]

In the Three Gorges Reservoir area, 78.1% of precipitation pH was measured below 5.6 by gathering 233 samples of precipitation in 2009-13. The forest ecological system in this area was threatened. In order to quantify the acid risk to the forest ecosystem, acid deposition and nutrient nitrogen critical loads in the area were estimated using simple mass balance equations based on the critical load concept. The values of acid deposition and nutrient nitrogen critical loads varied from 0 to 10.3 keq·ha-1·yr-1 and from 0 to 3.5 keq·ha-1·yr-1, respectively. Among them, acid critical loads were mostly sensitive to net nitrogen uptake and the ratio of Bc to Al. The accuracy of two parameters improved for reducing the evaluation error of critical loads. And then, exceedance of critical loads was calculated on the basis of critical loads. For the forest soil, exceedance of critical loads were predicted (0-2.1 keq·ha-1·yr-1). Acid critical loads were exceeded approximately 4.8% across the entire region, which affected nutrient pools in forested mineral soils. For the forest plants, 20.1% of the forests were predicted to exceed the empirical critical load. In addition, plant species diversity was significantly reduced with the increase of nitrogen deposition. This suggested that forest soil and plants have been adversely affected by acid deposition in some regions of the reservoir area. Thus, the impact of acid deposition on the forest ecosystem can provide key protection regions for the government and a basis for the implementation of emissions reduction policy. [ABSTRACT FROM AUTHOR]

Dihydroartemisinin (DHA) is an important derivative of the herb medicine Artemisia annua L., used in ancient China. DHA is currently used worldwide to treat malaria by killing malaria-causing parasites. In addition to this prominent effect, DHA is thought to regulate cellular functions, such as angiogenesis, tumor cell growth, and immunity. Nonetheless, how DHA affects T cell function remains poorly understood. We found that DHA potently suppressed Th cell differentiation in vitro. Unexpectedly, however, DHA greatly promoted regulatory T cell (Treg) generation in a manner dependent on the TGF-pR:Smad signal. In addition, DHA treatment effectively reduced onset of experimental autoimmune encephalomyelitis (EAE) and ameliorated on-going EAE in mice. Administration of DHA significantly decreased Th but increased Tregs in EAE-inflicted mice, without apparent global immune suppression. Moreover, DHA modulated the mammalian target of rapamycin (mTOR) pathway, because mTOR signal was attenuated in T cells upon DHA treatment. Importantly, enhanced Akt activity neutralized DHA-mediated effects on T cells in an mTOR-dependent fashion. This study therefore reveals a novel immune regulatory function of DHA in reciprocally regulating Th and Treg cell generation through the modulating mTOR pathway. It addresses how DHA regulates immune function and suggests a new type of drug for treating diseases in which mTOR activity is to be tempered. [ABSTRACT FROM AUTHOR]

TGF-β modulates immune response by suppressing non-regulatory T (Treg) function and promoting Treg function. The question of whether TGF-β achieves distinct effects on non-Treg and Treg cells through discrete signaling pathways remains outstanding. In this study, we investigated the requirements of Smad-dependent and -independent TGF-β signaling for T-cell function. Smad2 and Smad3 double deficiency in T cells led to lethal inflammatory disorder in mice. Non-Treg cells were spontaneously activated and produced effector cytokines in vivo on deletion of both Smad2 and Smad3. In addition, TGF-β failed to suppress T helper differentiation efficiently and to promote induced Treg generation of non-Treg cells lacking both Smad2 and Smad3, suggesting that Smad-dependent signaling is obligatory to mediate TGF-β function in non-Treg cells. Unexpectedly, however, the development, homeostasis, and function of Treg cells remained intact in the absence of Smad2 and Smad3, suggesting that the Smad-independent pathway is important for Treg function. Indeed, Treg-specific deletion of TGF-β-activated kinase 1 led to failed Treg homeostasis and lethal immune disorder in mice. Therefore, Smad-dependent and -independent TGF-β signaling discretely controls non-Treg and Treg function to modulate immune tolerance and immune homeostasis. [ABSTRACT FROM AUTHOR]

The PRMS_Storm model was built as a storm event, distributed hydrological model for studying the hydrological effects of forest composition and spatial distribution on storm-flow volume and peakflow rates in the Xiangshuixi Watershed in the Three Gorges Reservoir Area, in the Yangtze River Basin in southwestern China. We developed three simulation scenarios based on forest composition and their spatial arrangements across the watershed, including all mixed conifer-evergreen broadleaf forests (Scenario 1), all mixed evergreen broadleaf forests (Scenario 2), and mixed conifer + evergreen broadleaf + shrub forests (Scenario 3). We examined 11 storm events observed during 2002-2005. Compared with the existing forest covers, modeling results suggested that the amount of overland flow was reduced by 21, 23, and 22%, and the interflow increased by 16, 88, and 30%, for Scenarios 1, 2, and 3, respectively. During the same time, peakflow rates were reduced by 20.8, 9.6, and 18.9%, respectively. The reduction of peakflow rates was most significant when rainfall intensity exceeded 0.8 mm/min and events with a short duration and effect was minor when rainfall intensity was below 0.5 mm/min. In general, we found that Scenarios 1 and 3 were preferred for reducing storm-flow volume and peakflow rates due to their higher interception rates, large soil water holding capacity, and higher soil infiltration capacity. The modeled results suggested soil properties are important in affecting the flow processes and thus forest composition and forest spatial distributions will affect storm-flow volume and peakflow rates at the watershed scale. To maximize flood reduction functions of a watershed, high priority should be given to those forest types (Scenarios 1 and 3) in reforestation practices in the study region. This study suggests both forest composition and spatial pattern are important reforestation designs for flood reduction in the Three Gorges Reservoir Area. [ABSTRACT FROM AUTHOR]

In this article the authors discuss how the exploitation of wild Chinese herbs could lead to environmental degradation and the possible loss of the resource. They note the importance of herbs in traditional Chinese medicines as a substitute for more costly, synthetic drugs and discuss the environmental impact of both the expansion of the Chinese medicinal herb industry and the failure of the Chinese government to provide subsidies for the cultivation of Chinese herbs.

The article focuses on the one-step rolling fabrication of tubular VO2 bolometers for uncooled infrared detection. Topics discussed include enhanced thermal insulation, light absorption, and temperature sensitivity, as well as the potential to bridge the performance and cost gap between photon and thermal detectors.

Abacus-based mental calculation (AMC) involves temporary storage and manipulation of an imaginary abacus closely related to the function of visuospatial working memory (VSWM). The present study thus investigated the effects of AMC training on VSWM and its neural correlates. A total of 144 human subjects (67 boys) were assigned to AMC or control groups at their entry to primary school. The AMC group received 2 h AMC training per week for 5 school years, whereas the control group spent the time in activities, such as conventional calculation and reading. Raven's Intelligence Test was administered both before and after training. Two arithmetic tests and a VSWM task were conducted after training. Among these participants, fMRI data were collected from 64 children for the VSWM task. Behavioral results indicated that the AMC group outperformed controls on both arithmetic and VSWM tasks, but not on Raven's Intelligence Test. While the two groups activated similar regions during the VSWM task, the AMC group showed greater activation than the controls in frontal, parietal, and occipital areas. Interestingly, the activation of right middle frontal gyrus mediated the relation between the arithmetic ability and the VSWM performance in the AMC group, suggesting that the frontal region may be the neural substrate underlying the transfer effect from AMC training to VSWM. Although the transfer effects seem quite limited considering the length and intensity of the training, these findings suggest that long-term AMC training not only improves arithmetic ability but also has a potential positive effect on VSWM. [ABSTRACT FROM AUTHOR]

Background: Alfalfa (Medicago sativa) is one of the most important legume forage species in China and many other countries of the world. It provides a quality source of proteins and minerals to animals. Genetic underpinnings for these important traits, however, are elusive. An alfalfa (M. sativa) association mapping study for six traits, namely crude protein (CP), rumen undegraded protein (RUP), and four mineral elements (Ca, K, Mg and P), was conducted in three consecutive years using a large collection encompassing 336 genotypes genotyped with 85 simple sequence repeat (SSR) markers. Results: All the traits were significantly influenced by genotype, environment, and genotype × environment interaction. Eight-five significant associations (P < 0.005) were identified. Among these, five associations with Ca were repeatedly observed and six co-localized associations were identified. Conclusions: The identified marker alleles significantly associated with the traits provided important information for understanding genetic controls of alfalfa quality. The markers could be used in assisting selection for the individual traits in breeding populations for developing new alfalfa cultivars. [ABSTRACT FROM AUTHOR]

Currently, although prevalent location privacy methods based on k-anonymizing spatial regions (K-ASRs) can achieve privacy protection by sacrificing the quality of service (QoS), users cannot obtain accurate query results. To address this problem, it proposes a new location privacy-preserving k-anonymity method based on the credible chain with two major features. First, the optimal k value for the current user is determined according to the user's environment and social attributes. Second, rather than forming an anonymizing spatial region (ASR), the trusted third party (TTP) generates a fake trajectory that contains k location nodes based on properties of the credible chain. In addition, location-based services (LBS) queries are conducted based on the trajectory, and privacy level is evaluated by instancing θ privacy. Simulation results and experimental analysis demonstrate the effectiveness and availability of the proposed method. Compared with methods based on ASR, the proposed method guarantees 100% QoS. [ABSTRACT FROM AUTHOR]

Background: In vivo kinetics and frequencies of epitope-specific CD4 T cells in lymphoid compartments during M. tuberculosis infection and their resting memory pool after BCG vaccination remain unknown. Methodology/Findings: Macaque DR*W201 tetramer loaded with Ag85B peptide 65 was developed to directly measure epitope-specific CD4 T cells in blood and tissues form macaques after M. tuberculosis infection or BCG vaccination via direct staining and tetramer-enriched approach. The tetramer-based enrichment approach showed that P65 epitope-specific CD4 T cells emerged at mean frequencies of ∼500 and ∼4500 per 107 PBL at days 28 and 42, respectively, and at day 63 increased further to ∼22,000/107 PBL after M. tuberculosis infection. Direct tetramer staining showed that the tetramerbound P65-specific T cells constituted about 0.2-0.3% of CD4 T cells in PBL, lymph nodes, spleens, and lungs at day 63 postinfection. 10-fold expansion of these tetramer-bound epitope-specific CD4 T cells was seen after the P65 peptide stimulation of PBL and tissue lymphocytes. The tetramer-based enrichment approach detected BCG-elicited resting memory P65-specific CD4 T cells at a mean frequency of 2,700 per 107 PBL. Significance: Our work represents the first elucidation of in vivo kinetics and frequencies for tetramer-bound epitope-specific CD4 T cells in the blood, lymphoid tissues and lungs over times after M. tuberculosis infection, and BCG immunization. [ABSTRACT FROM AUTHOR]