Z-source matrix rectifier

This paper presents a novel Z-source matrix rectifier(ZSMR). To overcome the inherent disadvantage that the voltage transfer ratio for traditional matrix rectifier cannot be more than 0.866, a Z-source network has been combined with the matrix rectifier. The proposed rectifier realizes a voltage-boost function and the Z-source network also serves as power storage and guarantees double filtration grade at the output of the rectifier. The open-circuit zero state is required to obtain the voltage-boost function and ensure the output angle of the current vector to be invariant to obtain the expected power factor. In addition, to widely extend the voltage transfer ratio of the proposed rectifier, this paper presents the switched-inductor matrix rectifier(SL-ZSMR) and tapped-inductor matrix rectifier(TL-ZSMR). The corresponding circuit topologies, control strategies and operating principles are introduced. Both simulation and experiment results are shown to verify the theoretical analysis

Intermediate coherent-phase(PB) states of radiation fields and their nonclassical properties

Intermediate states interpolating coherent states and Pegg-Barnett phase states are investigated using the ladder operator approach. These states reduce to coherent and Pegg-Barnett phase states in two different limits. Statistical and squeezing properties are studied in detail.Comment: 9 pages, 3 EPS figures, use epsf.sty. Accepted for publication in Phys.Lett.

Cheating your apps: black-box adversarial attacks on deep learning apps

Deep learning is a powerful technique to boost application performance in various fields, including face recognition, image classification, natural language understanding, and recommendation system. With the rapid increase in the computing power of mobile devices, developers can embed deep learning models into their apps for building more competitive products with more accurate and faster responses. Although there are several works of adversarial attacks against deep learning models in apps, they all need information about the models' internals (i.e., structures and weights) or need to modify the models. In this paper, we propose an effective black-box approach by training substitute models to spoof the deep learning systems inside the apps. We evaluate our approach on 10 real-world deep-learning apps from Google Play to perform black-box adversarial attacks. Through the study, we find three factors that can affect the performance of attacks. Our approach can reach a relatively high attack success rate of 66.60% on average. Compared with other adversarial attacks on mobile deep learning models, in terms of the average attack success rates, our approach outperforms its counterparts by 27.63%

Contrasting nutrients input along with groundwater discharge to east Dongting Lake, central China: A geological perspective

The spatial patterns of lacustrine groundwater discharge (LGD) and associated nutrient inputs are crucial for effective management and protection of lakes. Multiple factors have been found to influence the spatial differences in LGD rates and associated nutrients loads, but the influence of geological conditions on the differences have not been well understood. In this study, we quantified LGD rates and associated nutrients loads on the west and east of the lake with contrasting geological conditions of East Dongting Lake (EDL) within central Yangtze catchment and discuss the influence of geology on the spatial differences, through 222Rn mass-balance model, water chemistry coupled with existing geological data. The results showed that LGD rates were 34.76 ± 23.36 mm/d in the east EDL which is characterized by hilly geomorphy, deep/fast/narrow flowing, coarse-grained lakebed and large hydraulic gradients (0.004–0.006). Surprisingly, LGD rates were higher (71.47 ± 52.16 mm/d) in the west EDL which is characterized by alluvial-lacustrine plain geomorphology, shallow/sluggish flowing, clayey or silty lakebed and low hydraulic gradients (0.0002–0.0015). The remaining factor determining the higher LGD rates in the west EDL is the permeability of the porous aquifer connected with the lake. The groundwater around the east EDL existed in a less confined environment, and frequent flushing led to low concentrations of nutrients. By contrast, rapid burial of sediments and deposition of paleo-lake sediments since Last Deglaciation formed an organic-rich and reducing environment, which facilitated the enrichment of geogenic nutrients. As a result, the loads of LGD-derived nutrients in the west generally exceeded that in the east by one order of magnitude. The study provides new understanding of the spatial differences in LGD and associated nutrients input to the large lakes resulting from variations in geological conditions, thus serving as a reference for ecological protection of lakes

Effect of angiopoietin 4 on odontogenic differentiation of dental pulp stem cells

Objective To investigate the effects of angiopoietin 4 (ANGPT4) on the odontogenic differentiation of human dental pulp stem cells. Methods This study has been reviewed and approved by the Ethics Committee, and informed consent has been obtained from patients. Human premolars were fixed, decalcified, dehydrated, embedded, and sectioned. Immunofluorescence staining was used to observe the expression and localization of ANGPT4. Human dental pulp stem cells (hDPSCs) were isolated and cultured in vitro. The growth state and morphology of hDPSCs were observed under an inverted phase contrast microscope. The expression of cell surface-related molecular markers was detected by flow cytometry. Alkaline phosphatase and alizarin red S staining were used to detect the odontogenic differentiation potential of hDPSCs. Oil-red O staining was used to detect the adipogenic differentiation potential of hDPSCs. RNA was extracted from hDPSCs at different time points after odontogenic induction, and RT-qPCR was used to analyze the mRNA expression of ANGPT4 and odontogenic-related genes during the odontogenic differentiation of hDPSCs in vitro. siRNA gene silencing technology was used to silence the expression of ANGPT4 in hDPSCs, and the silencing efficiency was detected by RT-qPCR and Western Blot. After silencing ANGPT4 in hDPSCs for 24 h, odontogenic induction was performed. Alkaline phosphatase and alizarin red S staining were performed on the 7th and 14th of induction to detect the odontogenic differentiation ability of hDPSCs after silencing ANGPT4. Results Immunofluorescence staining of human premolars showed that ANGPT4 was expressed in odontoblasts and sub-odontoblastic cell-rich zone. hDPSCs were in good condition after 14 days of isolation and culture. Under the microscope, multiple cell colonies were observed, and the cell morphology was uniform and long spindle-shaped. The results of flow cytometry showed that hDPSCs expressed mesenchymal stem cell markers CD105 (90.42%) and CD90 (97.15%), but did not express hematopoietic cell markers CD45 (0.01%) and CD34 (0.08%). After odontogenic and adipogenic induction of hDPSCs, alkaline phosphatase staining, alizarin red S staining and oil red O staining were positive. The results of RT-qPCR after the odontogenic induction of hDPSCs showed that ANGPT4 was highly expressed on the 5th, 7th, 11th and 14th days of differentiation of hDPSCs (P<0.05), with the highest expression level on the 5th day. After hDPSCs were transfected with si-ANGPT4, the expression of ANGPT4 mRNA and protein was significantly down-regulated (P<0.05). The results of alkaline phosphatase staining showed that ALP staining intensity and area in the si-ANGPT4 group were significantly lower than those in the negative control. Alizarin red S staining showed that the formation of calcium nodules in the si-ANGPT4 group was significantly lower than that in the negative control. Conclusion ANGPT4 was expressed in odontoblasts and sub-odontoblastic cell-rich zone of human premolars. ANGPT4 may be a factor to promote the odontogenic differentiation of hDPSCs

Titanium Carbide Composite Hollow Cobalt Sulfide Heterojunction with Function of Promoting Electron Migration for Efficiency Photo-Assisted Electro-Fenton Cathode

Constructing heterostructure within electrocatalysts proves to be an attractive approach to adjust the interfacial charge redistribution to promote the adsorption of reactive species and accelerate the charge transfer. Herein, we present the one-pot solvothermal synthesis of Ti3C2 supported hollow CoS2/CoS microsphere heterostructure with uneven charge distribution as the cathodic catalyst, which displays a superior quasi-first-order degradation rate (0.031 min−1) for sulfamethazine (SMT) in photo-assisted electric–Fenton (EF) process. CoS2/CoS/Ti3C2 is proven to favor the 2e− oxygen reduction reaction (ORR), with H2O2 selectivity up to 76%. The built-in potential present in the heterojunction helps to accelerate electron transfer, thus promoting the production of H2O2. Subsequently, H2O2 is rapidly activated to produce ∙OH due to the synergistic effect of Co and S. Notably, CoS2/CoS/Ti3C2 exhibits enhanced photo-assisted EF (PEF) performance under light. The excellent photocatalysis properties of CoS2/CoS/Ti3C2 are attributed to that the unique hollow microsphere structure of catalyst improves the light absorption, and the uneven charge distribution of CoS2/CoS heterojunctions promotes the separation of photo-generated holes and electrons. Given the above advantages, CoS2/CoS/Ti3C2 cathode delivers a high degradation rate of 98.5%, 91.8%, and 94.5% for SMT, bisphenol A, and sulfadiazine, respectively, with TOC removal efficiency of 76% for SMT with 120 min. This work provides a novel light of the design and construction of efficient PEF cathodes for the treatment of antibiotic wastewater

Climate Change Promotes the Large-Scale Population Growth of <i>Grapholita molesta</i> (Busck) (Lepidoptera: Tortricidae) within Peach Orchards in China

Cosmopolitan agricultural herbivorous pests are provided with a wide range of potential hosts. Therefore, they have high carrying capacity, and can cause extremely severe damage in agroecosystems. Understanding the ecological mechanisms of their population dynamics, especially as they relate to large-scale meteorological variations and geographical landscape influences, can help us to reveal how they became such important pests. The oriental fruit moth, Grapholita molesta, is a typical example of a significant pest distributed on a large scale, which is capable of damaging fruit trees of economic value such as peach, apple, pear, etc. This pest not only occurs in China, but exists on all continents except Antarctica. In order to prevent major pests and diseases, a system of plant protection has been established gradually in peach orchards within the Modern Agro-industry Technology Research System in China (CARS) since 2009. In the system, we collected the monitoring data of G. molesta by using pheromone traps at 17 experimental stations, and then used the corresponding climate data (temperature and precipitation) to explore the link between climate factors using mixed models. The results show that both monthly mean temperature and precipitation had a significant positive correlation with the occurrence of G. molesta. Therefore, global warming with higher levels of precipitation may favor G. molesta, allowing it to outperform other potential pests at the population level in peach orchards, on a large scale

Programmable Design of Isothermal Nucleic Acid Diagnostic Assays through Abstraction-based Models

The aggregated patient data is provided in the publication associated with this dataset (Supplementary Information Table S4). Individual patient data is available from corresponding authors Professor Jonathan Cooper ([email protected]) and Dr. Gaolian Xu ([email protected]), upon motivated request

Supplementary document for Anomalous generalized Brewster effect and ultra-broadband reflectionless Brewster metasurfaces - 5982247.pdf

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