This paper presents a novel three-coil reconnection electromagnetic launcher (TCREL). Analytical calculations and simulation results indicated that not only does this model possess a higher ...structural strength, but also the launching efficiency is improved effectively compared with that of the traditional reconnection electromagnetic launcher (REL). In addition, take the TCREL model as an independent module; a toroidal REL (TREL) model can be obtained after several modules are uniformly placed and fixed around the circumference. The TREL model can reduce the magnetic flux leakage among driving coils, and further improves the launching efficiency. To verify the conceptual feasibility, two-stage TCREL and REL models were built and tested. The experiments demonstrate that the TCREL model possesses better launching performance than does the REL model; the former can obtain the desired launching efficiency of 15.818% but the latter only 8.248% in the contrast experiment. The experimental results are also in accordance with the simulation results.
Aspergillus flavus (A. flavus) is a ubiquitous saprophytic and pathogenic fungus that produces the aflatoxin carcinogen, and A. flavus can have tremendous economic and health impacts worldwide. ...Increasing evidence demonstrates that lysine succinylation plays an important regulatory role in metabolic processes in both bacterial and human cells. However, little is known about the extent and function of lysine succinylation in A. flavus. Here, we performed a global succinylome analysis of A. flavus using high accuracy nano-LC-MS/MS in combination with the enrichment of succinylated peptides from digested cell lysates and subsequent peptide identification. In total, 985 succinylation sites on 349 succinylated proteins were identified in this pathogen. Bioinformatics analysis revealed that the succinylated proteins were involved in various biological processes and were particularly enriched in the aflatoxin biosynthesis process. Site-specific mutagenesis and biochemical studies showed that lysine succinylation on the norsolorinic acid reductase NorA (AflE), a key enzyme in aflatoxins biosynthesis, can affect the production of sclerotia and aflatoxins biosynthesis in A. flavus. Together, our findings reveal widespread roles for lysine succinylation in regulating metabolism and aflatoxins biosynthesis in A. flavus. Our data provide a rich resource for functional analyses of lysine succinylation and facilitate the dissection of metabolic networks in this pathogen.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
DNA methylation is essential for epigenetic regulation of gene transcription and development in many animals, plants and fungi. We investigated whether DNA methylation plays a role in the development ...and secondary metabolism of Aspergillus flavus, identified the DmtA methyltransferase from A. flavus, and produced a dmtA knock-out mutant by replacing the dmtA coding sequence with the pyrG selectable marker. The A. flavus dmtA null mutant lines produced white fluffy mycelium in liquid medium, and displayed a slightly flavescent conidial pigmentation compared with the normal yellow of the wild-type strain when grown on agar. The ΔdmtA lines exhibited decreased conidiation and aflatoxin (AF) biosynthesis, compared with the wild-type line, suggesting that the DmtA knock-out affected the transcriptional level of genes in the AF cluster. In particular, sclerotia development and host colonization were altered in the dmtA null mutants. Green fluorescent protein tagging at the C-terminus of DmtA showed that DmtA localized to the nucleus and cytoplasm. DNA methylation content measurements in the dmtA mutants revealed no widespread DNA methylation in the mutants or wild-type lines. Thus, our findings suggest that DmtA, apart from being a C-5 cytosine methyltransferase in A. flavus, contributes to asexual development, aflatoxin biosynthesis, sclerotial production and virulence.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
An efficient and more accurate millimeter-wave imaging algorithm, applied to a close-range monostatic personnel screening system, with consideration of dual path propagation loss, is presented in ...this paper. The algorithm is developed in accordance with a more rigorous physical model for the monostatic system. The physical model treats incident waves and scattered waves as spherical waves with a more rigorous amplitude term as per electromagnetic theory. As a result, the proposed method can achieve a better focusing effect for multiple targets in different range planes. Since the mathematical methods in classical algorithms, such as spherical wave decomposition and Weyl identity, cannot handle the corresponding mathematical model, the proposed algorithm is derived through the method of stationary phase (MSP). The algorithm has been validated by numerical simulations and laboratory experiments. Good performance in terms of computational efficiency and accuracy has been observed. The synthetic reconstruction results show that the proposed algorithm has significant advantages compared with the classical algorithms, and the reconstruction by using full-wave data generated by FEKO further verifies the validity of the proposed algorithm. Finally, the proposed algorithm performs as expected over real data acquired by our laboratory prototype.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Candida albicans, a commensal organism and a pathogen of humans, can switch stochastically between a white phase and an opaque phase without an intermediate phase. The white and opaque phases have ...distinct cell shapes and gene expression programs. Once switched, each phase is stable for many cell divisions. White-opaque switching is under al-α2 repression and therefore only happens in a or α cells. Mechanisms that control the switching are unknown. Here, we identify Wor1 (white-opaque regulator 1) as a master regulator of white-opaque switching. The deletion of WOR1 blocks opaque cell formation. The ectopic expression of WOR1 converts all cells to stable opaque cells in a or a cells. In addition, the ectopic expression of WOR1 in a/α cells is sufficient to induce opaque cell formation. Importantly, WOR1 expression displays an all-or-none pattern. It is undetectable in white cells, and it is highly expressed in opaque cells. The ectopic expression of Wor1 induces the transcription of WORI from the WOR1 locus, which correlates with the switch to opaque phase. We present genetic evidence for feedback regulation of WOR1 transcription. The feedback regulation explains the bistable and stochastic nature of white-opaque switching.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
(
.
) is an opportunistic pathogen in humans and possesses a white-opaque heritable switching system. Wor1 is a master regulator of white-opaque switching and is essential for opaque cell formation ...in
.
. However, the regulatory network of Wor1 in white-opaque switching is still vague. In this study, we obtain a series of Wor1-interacting proteins using LexA-Wor1 as bait. Among these proteins, function unknown now 30 (Fun30) interacts with Wor1
and
. Fun30 expression is upregulated in opaque cells at the transcriptional and protein levels. Loss of
attenuates white-to-opaque switching, while ectopic expression of
significantly increases white-to-opaque switching in an ATPase activity-dependent manner. Furthermore,
upregulation is dependent on CO
; loss of
, a key CO
-sensing transcriptional regulator, abolishes
upregulation. Interestingly, deletion of
affects the
expression regulation feedback loop. Thus, our results indicate that the chromatin remodeller Fun30 interacts with Wor1 and is required for
expression and opaque cell formation.
A capacitor made of high-temperature superconducting (HTS) electrode plates and a dielectric layer, or "HTS capacitor" for short, has the potential advantages of working with other HTS devices at 77 ...K and producing low conductive loss at high frequency. It may have a specific application to cryogenic systems at high frequency, such as superconducting wireless power transfer (SWPT) systems. Working with HTS resonant coil in an adiabatic container, the HTS capacitor can also reduce the heat leakage of the cooling system. Considering a lack of relevant experimental study at present, an HTS capacitor composed of YBCO (YBa 2 Cu 3 O 7-x ) tapes and a polyimide layer is proposed in this paper and tested in an SWPT system. Its characteristics and influences on the SWPT system are presented in detail by theoretic analysis and experimental investigation. A comparative experiment is carried out between the fabricated HTS capacitor and other capacitors made from normal materials. Finally, it is confirmed experimentally that the HTS capacitor can have a high-quality factor, work with the HTS resonant coil normally at 77 K, and provide the SWPT system with a performance enhancement.
A design of high-temperature superconducting bandpass filter based on split-ring resonator (SRR) structures is presented in this paper. The SRR has been considered as a classical element for ...metamaterials and exhibits characteristics of subwavelength resonator, hence can aid in the compact design of filters. Filter has been simulated and optimized using Sonnet software. The measured results of the filter have good consistency with the simulated results and show good band pass characteristics. The center frequency of the filter measured at 70 K was 2.515 GHz, the rectangle coefficient was 1.22, and the insertion loss was 0.1 dB at the center frequency.
In this paper, a magnetic resonance wireless power transfer (WPT) system with two coils using superconductor and ferromagnetic (SC-FM) metamaterials was constructed and tested. SC-FM metamaterials ...were used in the WPT system to improve the transfer efficiency of the magnetic resonance WPT system. Three kinds of resonance coils were designed and the effects on the WPT system of different resonance coils using SC-FM metamaterials were investigated. This involved designing and conducting several kinds of WPT experiments with, and without, the SC-FM metamaterials. The results are then presented and analyzed. It is shown that the SC-FM metamaterials are able to improve the transfer efficiency of a WPT system.
In
, the nitrogen metabolite repression (NMR) regulator NmrA plays a major role in regulating the activity of the GATA transcription factor AreA during nitrogen metabolism. However, the function of
...in
has not been previously studied. Here, we report the identification and functional analysis of
in
. Our work showed that the amino acid sequences of NmrA are highly conserved among
species and that
NmrA protein contains a canonical Rossmann fold motif. Deletion of
slowed the growth of
but significantly increased conidiation and sclerotia production. Moreover, seed infection experiments indicated that
is required for the invasive virulence of
. In addition, the Δ
mutant showed increased sensitivity to rapamycin and methyl methanesulfonate, suggesting that
could be responsive to target of rapamycin signaling and DNA damage. Furthermore, quantitative real-time reverse transcription polymerase chain reaction analysis suggested that
might interact with other nitrogen regulatory and catabolic genes. Our study provides a better understanding of NMR and the nitrogen metabolism network in fungi.
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