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[Objectives] In this paper, the harmonic characteristics of output voltage for a matrix converter (MC)in marine electric propulsion system are studied.[Methods] Based on triple Fourier Series,an analytical calculation method to determine harmonic components of MC is proposed. Firstly,combined with the triple Fourier Series,the analytical results of the harmonic components of output voltage for a matrix converter under the direct transfer function modulation strategy are derived. Then according to the results,the harmonic distribution characteristics as well as main harmonic components are analyzed. Finally,the feasibility of the method and the accuracy of the analysis conclusions are verified by comparative analysis against the Fast Fourier Transform(FFT) results of the output voltage waveform obtained from the test.[Results] It is found that the amplitude of common mode components with high frequency of fc ±fin and 2fc ±fin are higher.[Conclusions] This method can determine the amplitudes and frequency of different harmonic components precisely,which provides a theoretical basis for the study of harmonic suppression,and also improves the theory of harmonic analysis of matrix converter.

Newcastle disease virus (NDV) infects poultry and antagonizes host immunity via several mechanisms. Dendritic cells (DCs) are characterized as specialized antigen presenting cells, bridging innate and adaptive immunity and regulating host resistance to viral invasion. However, there is little specific knowledge of the role of DCs in NDV infection. In this study, the representative NDV lentogenic strain LaSota was used to explore whether murine bone marrow derived DCs mature following infection. We examined surface molecule expression and cytokine release from DCs as well as proliferation and activation of T cells in vivo and in vitro in the context of NDV. The results demonstrated that infection with lentogenic strain LaSota induced a phenotypic maturation of immature DCs (imDCs), which actually led to curtailed T cell responses. Upon infection, the phenotypic maturation of DCs was reflected by markedly enhanced MHC and costimulatory molecule expression and secretion of proinflammatory cytokines. Nevertheless, NDV-infected DCs produced the anti-inflammatory cytokine IL-10 and attenuated T cell proliferation, inducing Th2-biased responses. Therefore, our study reveals a novel understanding that DCs are phenotypically mature but dysfunctional in priming T cell responses during NDV infection.

We have recently identified the MYC proto-oncogene, bHLH transcription factor (MYC, best known as c-Myc)-responsive pan-cancer lncRNA c-Myc-Inducible Long noncoding RNA Inactivating P53 (MILIP) as an oncogenic driver. Our studies show that MILIP facilitates tumor protein p53 (TP53, best known as p53) turnover by reducing its SUMOylation through suppressing tripartite-motif family-like 2 (TRIML2), thus promoting cell survival, proliferation, and tumorigenicity. MILIP may thus represent an anti-cancer target for counteracting the c-Myc axis.

The Ultra-Reliable Low-Latency Communication (URLLC) is expected to be an important feature of 5G and beyond networks. Supporting URLLC in a resource-efficient manner demands optimal Modulation and Coding Scheme (MCS) selection and spectrum allocation. This paper presents a study on MCS selection and spectrum allocation to support URLLC. The essential idea is to establish an analytical connection between the delay and reliability requirements of URLLC data transmission and the underlying MCS selection and spectrum allocation. In particular, the connection factors in fundamental aspects of wireless data communication include channel quality, coding and modulation, spectrum allocation and data traffic characteristics. With this connection, MCS selection and spectrum allocation can be efficiently performed based on the delay and reliability requirements of URLLC. Theoretical results in the scenario of a 5G New Radio system are presented, where the Signal-to-Noise Ratio (SNR) thresholds for adaptive MCS selection, data-transmission rate and delay, as well as spectrum allocation under different configurations, including data duplication, are discussed. Simulation results are also obtained and compared with the theoretical results, which validate the analysis and its efficiency.

A compact ultra-wideband and flexible MEMS monopole antenna fed by coplanar waveguide(CPW) was proposed, which has the characteristics of simple structure, light quality, ease of integration and flexible bending. The antenna used a PDMS material with outstanding flexibility and great self-recovery as its substrate. The disc shaped metal radiation structure was designed on the side of the flexible substrate, and the CPW structure was integrated with the antenna on the same side of the substrate. In the experiment, it is proved that the combined treatment of oxygen plasma and SDS can effectively improve the adhesion effect of photoresist and PDMS surface. The MEMS monopole flexible antennas fed by CPW were separately fabricated on the PDMS flexible substrate by metal lift-off process based on AZ6130，RZJ304 and AZ5214E photoresist, and the performances and the lift-off difficulty of the antennas fabricated based on different photoresists were compared. The frequency band of the antenna is 3.3 GHz to 5 GHz, of which the impedance matching is perfect and the radiation directivity is stable. It can be applied to 5G communication system, and also provides a reference for the research of flexible antenna.

Laser Doppler Velocimetry (LDV) has been employed to determine pseudo-turbulence characteristics of the flow field around bubble train forming in non-Newtonian caboxymethylcellulose (CMC) aqueous solution at low gas flow rate condition. The Reynolds stress and turbulent intensity of the liquid were investigated by means of Reynolds time-averaged method. The experimental results show that axial Reynolds stress rises greatly and then fluctuates slightly with the vertical height, whereas displays symmetrical Gaussian distribution in the horizontal direction; Radial Reynolds stress changes nonobviously in the vertical direction, but increases followed by a decrease in the horizontal direction. The axial turbulent intensity begins to wave to some degree with the height for near vertical axis passing through orifice center, but maintains constant within bubble channel in the horizontal direction; Radial turbulent intensity gets down with the vertical height, compared with the opposite trend of its variation with the horizontal distance.

Glioma, especially glioblastoma, is pathologically characterized by high aggressiveness, which largely contributed to the ineffectiveness of current therapies. It has been recently reported that intrinsic PD-L1 can regulate tumor malignancy, whereas underlying mechanisms remain mostly unclear. Here, we report a novel mechanism by which PD-L1 promotes glioma cell infiltration. In orthotopic glioma models, PD-L1 expression was up-regulated predominantly in glioma cells in the infiltrating front. For PD-L1-overexpressed glioma cells, PI3K/Akt and actin regulations were among the top six most altered signaling pathways as detected by RNA-sequencing. PD-L1 significantly activated Akt/F-actin signaling while suppressed autophagic signaling upon cell starvation. Mechanistically, PD-L1 preferentially bound to Akt among various PI3K/Akt signaling proteins. Serial truncation identified the interaction between the 128-237aa fragment of PD-L1 and the 112-480aa fragment of Akt, which facilitates the membrane translocation/activation of Akt, and was unaffected by Perifosin (specific p-Akt inhibitor targeting Akt PH-domain). Taken together, our data indicate that in glioma cells, PD-L1 is induced to prevent autophagic cytoskeleton collapse via Akt binding/activation, facilitating glioma cell invasion upon starvation stress.

Abstract Malaria at international borders presents particular challenges with regards to elimination. International borders share common malaria ecologies, yet neighboring countries are often at different stages of the control-to-elimination pathway. Herein, we present a case study on malaria, and its control, at the border between Saudi Arabia and Yemen. Malaria program activity reports, case data, and ancillary information have been assembled from national health information systems, archives, and other related sources. Information was analyzed as a semi-quantitative time series, between 2000 and 2017, to provide a plausibility framework to understand the possible contributions of factors related to control activities, conflict, economic development, migration, and climate. The malaria recession in the Yemeni border regions of Saudi Arabia is a likely consequence of multiple, coincidental factors, including scaled elimination activities, cross-border vector control, periods of low rainfall, and economic development. The temporal alignment of many of these factors suggests that economic development may have changed the receptivity to the extent that it mitigated against surges in vulnerability posed by imported malaria from its endemic neighbor Yemen. In many border areas of the world, malaria is likely to be sustained through a complex congruence of factors, including poverty, conflict, and migration.

Abstract In this study, the perovskite layers were prepared by two-step wet process with different CH3NH3I (MAI) concentrations. The cell structure was glass/FTO/TiO2-mesoporous/CH3NH3PbI3 (MAPbI3)/spiro-OMeTAD/Ag. The MAPbI3 perovskite films were prepared using high and low MAI concentrations in a two-step process. The perovskite films were optimized at different spin coating speed and different annealing temperatures to enhance the power conversion efficiency (PCE) of perovskite solar cells. The PCE of the resulting device based on the different perovskite morphologies was discussed. The PCE of the best cell was up to 17.42%, open circuit voltage of 0.97 V, short current density of 24.06 mA/cm2, and fill factor of 0.747.

A dual-polarized antenna with omnidirectional radiation and high isolation performance is proposed in this paper. The proposed antenna consists of courtyard-shaped metal frame, feeding network, and metal background. Working mechanism of the proposed antenna is analyzed by the theory of characteristic modes. Two orthogonal polarizations can be achieved by utilizing the orthogonal current distributions on the courtyard-shaped metal frame. In order to obtain the horizontal-polarized mode, eight slots etched on the walls of the courtyard-shaped metal frame are excited. A feeding network is placed at the inner part of courtyard-shaped metal frame for a compact design. Measured results show that the proposed antenna can cover the impedance bandwidth of 1.80–2.81 GHz for both polarizations with their corresponding isolations better than 35 dB. A peak gain of 7 dBi and a gain ripple less than 3 dB in the horizontal radiation plane are achieved. The proposed antenna can be applied in the indoor wireless communication.

This study examined teachers' perceptions and attitudes toward students with special education needs (SEN) in primary and secondary schools in Foshan city located in the Guangdong province. The factors affecting teachers' perceptions were investigated through a survey with 1,424 participants. The results indicated that the teachers' perceptions of students with SEN were influenced by gender, age, class teacher role, administrator role, subject taught, type of disability of students, school support resources, and job demands. The findings extended current understanding of the influential factors on teacher's perception. Moreover, it raised a concern for school level support that will contribute to the building of inclusive environment. Re-examination of the inclusive policy from the perspective of a whole school support approach is recommended.

The excess of low-density lipoprotein (LDL) strongly promotes the accumulation of cholesterol on the arterial wall, which can easily lead to the atherosclerotic cardiovascular diseases (ACDs). It is a challenge on how to recognize and quantify the LDL with a simple and sensitive analytical technology. Herein, β-cyclodextrins (β-CDs), acting as molecular receptors, can bind with LDL to form stable inclusion complexes via the multiple interactions, including electrostatic, van der Waals forces, hydrogen bonding and hydrophobic interactions. With the combination of gold nanoparticles (Au NPs) and β-CDs, we developed an electrochemical sensor providing an excellent molecular recognition and sensing performance towards LDL detection. The LDL dynamic adsorption behavior on the surface of the β-CD-Au electrode was explored by electrochemical impedance spectroscopy (EIS), displaying that the electron-transfer resistance (Ret) values were proportional to the LDL (positively charged apolipoprotein B-100) concentrations. The β-CD-Au modified sensor exhibited a high selectivity and sensitivity (978 kΩ·µM−1) toward LDL, especially in ultra-low concentrations compared with the common interferers HDL and HSA. Due to its excellent molecular recognition performance, β-CD-Au can be used as a sensing material to monitor LDL in human blood for preventing ACDs in the future.

A checklist of the subgenus Culicoides (Avaritia Fox) (Diptera: Ceratopogonidae: Culicoides) in China, currently including 57 species, is provided. Their full citations, more detailed locations of the type locality, and distribution of each species by province, and/or state of each species are also provided. Culicoides (Avaritia) fenggangensis Liu & Hou, sp. n. is described and illustrated, based on both male and female specimens from China. The new species is compared with its similar congeners, C. (A.) comparis Liu & Yu, 2005 and C. (A.) dentiformis McDonald & Lu, 1972.

Abstract Background Retinitis pigmentosa is a common genetic disease that causes retinal degeneration and blindness for which there is currently no curable treatment available. Vision preservation was observed in retinitis pigmentosa animal models after retinal stem cell transplantation. However, long-term safety studies and visual assessment have not been thoroughly tested in retinitis pigmentosa patients. Methods In our pre-clinical study, purified human fetal-derived retinal progenitor cells (RPCs) were transplanted into the diseased retina of Royal College of Surgeons (RCS) rats, a model of retinal degeneration. Based on these results, we conducted a phase I clinical trial to establish the safety and tolerability of transplantation of RPCs in eight patients with advanced retinitis pigmentosa. Patients were studied for 24 months. Results After RPC transplantation in RCS rats, we observed moderate recovery of vision and maintenance of the outer nuclear layer thickness. Most importantly, we did not find tumor formation or immune rejection. In the retinis pigmentosa patients given RPC injections, we also did not observe immunological rejection or tumorigenesis when immunosuppressive agents were not administered. We observed a significant improvement in visual acuity (P

Climate variability in decades requires detailed research aspect basin in order to take account of climate change attested, both in making various decisions applicative and at proper adaptation to these changes. Previous research results obtained in this section indicates that territory most vulnerable to climate change is largely located within the Danube basin within the territory of the Republic of Moldova. Therefore, the purpose of the proposed research in this paper was to record some changes in the current period and which are forecasts on thermal regime and precipitation in the scale time 2016-2035.

Current changes of the environment represent the major threats to the sustainable development and are one of the biggest problems, with negative consequences on the national economy. The accelerated pace of these changes is shareholder and by the manifestation of extreme events, which in recent years become more intense and frequent. The drought events frequent manifestation over the Republic of Moldova territory, in the context of climate change, requires a scientific monitoring adjusted.

Abstract Background Marbofloxacin is a veterinary fluoroquinolone with high activity against Pasteurella multocida. We evaluated it’s in vivo activity against P. multocida based on in vivo time-kill data in swine using a tissue-cage model. A series of dosages ranging from 0.15 to 2.5 mg/kg were administered intramuscularly after challenge with P. multocida type B, serotype 2. Results The ratio of the 24 h area under the concentration-time curve divided by the minimum inhibitory concentration (AUC24TCF/MIC) was the best PK/PD index correlated with the in vivo antibacterial effectiveness of marbofloxacin (R2 = 0.9279). The AUC24TCF/MIC necessary to achieve a 1-log10 CFU/ml reduction and a 3-log10 CFU/ml (90% of the maximum response) reduction as calculated by an inhibitory sigmoid Emax model were 13.48 h and 57.70 h, respectively. Conclusions Marbofloxacin is adequate for the treatment of swine infected with P. multocida. The tissue-cage model played a significant role in achieving these PK/PD results.

Abstract An ideal porous adsorbent toward uranium with not only large adsorption capacity and high selectivity but also broad applicability even under rigorous conditions is highly desirable but still extremely scarce. In this work, a porous adsorbent, namely [NH4]+[COF‐SO3−], prepared by ammoniating a SO3H‐decorated covalent organic framework (COF) enables remarkable performance for uranium extraction. Relative to the pristine SO3H‐decorated COF (COF‐SO3H) with uranium adsorption capacity of 360 mg g−1, the ammoniated counterpart of [NH4]+[COF‐SO3−] affords ultrahigh uranium uptake up to 851 mg g−1, creating a 2.4‐fold enhancement. Such a value is the highest among all reported porous adsorbents for uranium. Most importantly, a large distribution coefficient, KdU, up to 9.8 × 106 mL g−1 is observed, implying extremely strong affinity toward uranium. Consequently, [NH4]+[COF‐SO3−] affords highly selective adsorption of uranium over a broad range of metal ions such as SU/Cs = 821, SU/Na = 277, and SU/Sr = 124, making it as effective uranium adsorbent from seawater, resulting in amazing uranium adsorption capacity of 17.8 mg g−1. Moreover, its excellent chemostability also make it an effective uranium adsorbent even under rigorous conditions (pH = 1, 8, and 3 m acidity).

The craniofacial skeleton is the foundation of most stomatological treatments, including prosthodontics and maxillofacial surgery. Although histologically similar to the appendicular skeleton, the craniofacial skeleton manifests many unique properties in response to external stimuli and signals. However, the mandibular or maxillary bone marrow mesenchyme, which is the intrinsic foundation of the functions of craniofacial skeleton, has not been well studied, and its homeostasis mechanism remains elusive. Osteoporosis is a systemic disease that affects all skeletons and is characterized by bone mass loss. Osteoporotic bone marrow mesenchymal stem cells (BMMSCs) exhibit disturbed homeostasis and distorted lineage commitment. Many reports have shown that microRNAs (miRNAs) play important roles in regulating MSCs homeostasis. Here, to obtain a better understanding of mandibular bone marrow MSCs homeostasis, we isolated and cultured mandible marrow MSCs from mouse mandibles. Using miR-705 mimics and an inhibitor, we demonstrated that miR-705 played a vital role in shifting the mandibular MSCs lineage commitment in vitro. Utilizing an osteoporosis mouse model, we demonstrated that MSCs from ovariectomized (OVX) mouse mandibular bone marrow exhibited impaired osteogenic and excessive adipogenic differentiation. miR-705 was found overexpressed in OVX mandibular MSCs. The knock down of miR-705 in vitro partially attenuated the differentiation disorder of the OVX mandibular MSCs by upregulating the expression of osteogenic marker genes but suppressing adipogenic genes. Taken together, our findings provide a better understanding of the homeostasis mechanism of mandibular BMMSCs and a novel potential therapeutic target for treating mandibular osteoporosis.