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This paper builds up “disc-point” heat conduction models considering the nonuniform heat generating (NUHG) characteristic. Constructal optimizations are respectively carried out for the radial-pattern disc and tree-shaped discs with constant and variable cross-sectional high conductivity channels (HCCs) by minimizing the maximum temperature difference (MTD). For various NUHG conditions, the optimal constructs of the two kinds of discs are obtained, and the impacts of NUHG coefficient and width coefficient on the optimal results are analyzed in detail. The results indicate that for the tree-shaped disc with constant cross-sectional HCCs, the stems of the HCCs grow thicker and longer, while the branches become thinner and shorter when more heat is generated near the heat sink, and the high conductivity material should be distributed preferably where the heat sink is located to enhance the heat transfer performance (HTP). Meanwhile, the optimal tree-shaped disc tends to degrade into a radial-pattern disc when the number of the stems is less than 18. For the tree-shaped disc with variable cross-sectional HCCs, the twice minimized dimensionless MTD with the width coefficient of 1.7 is reduced by 4.3% in contrast with the width coefficient of 1, which demonstrates that applying the variable cross-sectional HCCs architecture can further improve its HTP. The constructal results obtained in this paper can contribute to the design of practical electronics.

Input-parallel output-series (IPOS)-based combined converter is usually used in the situation with low input voltage and high output voltage to satisfy the requirements in switch voltage stress reduction and power expansion. In such a system, the voltage balance of filter capacitor in the output side or current sharing in the input side usually used to guarantee the control performance of the conversion system. In this paper, a phase-shifted full bridge (PSFB)-based IPOS converter with modified connection of output filter circuit used for the wide variation of input voltage is proposed, which is beneficial to reduce ripple current of filter inductor significantly. A control scheme using the same phase shifting for the two different modules of this IPOS converter is detailedly investigated with both steady state and small signal model-based analysis, it manifests that special voltage balance and current sharing control scheme are not necessary for IPOS system under the common phase shifting control method. And the small signal transfer functions of this topology used for dual loop control system design are also developed. The simulation and experiment results are presented to validate the analysis and control scheme.

A bidirectional integrated bus voltage conditioner (IBVC) for an isolated phase-shifted full bridge (PSFB) dc/dc converter is proposed to reduce the dc bus voltage oscillations in a cascaded power converter system, where a load converter is controlled tightly with high-control bandwidth. In the proposed method, unlike conventional dc bus voltage stabilization methods for which auxiliary switches are used, the multiplexing utilization of the full bridge switches at the primary side of a PSFB is adopted. In this paper, to improve the dc bus voltage stability, an equivalent virtual resistor is implemented by applying the duty cycle regulation for both legs of the PSFB. The effectiveness of the proposed method on the dc voltage stabilization is examined through simulations and experiments. The achieved results reveal that the dc bus voltage stability is significantly improved with the proposed method.

In this paper, an analytical design space of power amplifiers (PAs) including the Class-A/B/J continuum for dynamic load modulation (DLM) at the current generator plane (CGP) is proposed based on the theory of load modulated (LM) continuous Class-B/J PAs. By introducing a biasing operation factor ρ, the theory of DLM PAs provides an analytical design space for all the operation modes from Class-B/J mode to Class-A mode. The analytical design space of DLM PAs shows that high efficiency is maintained at a large dynamic range of output power back-off (OPBO) with a purely resistive load modulation at the CGP when Class-B/J mode is performed. For deep Class-AB mode, the analytical design space of the DLM PAs shows that a combination of resistive and reactive load modulation at the CGP is used to maintain the high efficiency at the OPBO. The effectiveness of the proposed analytical design space is validated by load-pull measurements of a bare-chip gallium nitride (GaN) device.

Aims: In addition to its cardiotonic effect, Levosimendan (Levo) has been thought to have multiple cardiovascular benefits, including anti-inflammatory and anti-apoptotic effects. The present study was undertaken to determine whether the Levo pretreatment could attenuate myocardial apoptosis and inflammation and improve cardiac function in a swine model of coronary microembolization (CME). Materials and Methods: A total of 15 swine were randomly and equally divided into a sham-operated (control) group, CME group, and CME plus Levo group. Swine CME was induced by intracoronary injection of inertia plastic microspheres (42 μm diameter) into the left anterior descending (LAD) coronary artery, with or without pretreatment of Levo. Echocardiological measurements, a pathological examination, Terminal-deoxynucleoitidyl Transferase-Mediated dUTP Nick End-Labeling (TUNEL) staining, H and E staining, and Western blotting were performed to assess the functional, morphological, and molecular effects in CME. Results: The expression levels of caspase-3 and tumor necrosis factor-α (TNF-α) were increased in cardiomyocytes following CME. Downregulation of caspase-3 and TNF-α with Levo pretreatment was associated with improved cardiac troponin I (cTnI) and high sensitivity C-reactive protein. In addition, through Pearson correlation analysis, the left ventricular ejection fraction was negatively correlated with caspase-3, TNF-α, and cTnI. Conclusion: This study demonstrated that Levo pretreatment could significantly inhibit CME-induced myocardial apoptosis and inflammation and improve cardiac function. The data generated from this study provide a rationale for the development of myocardial apoptosis and inflammation-based therapeutic strategies for CME-induced myocardial injury.

Plant homeodomain (PHD) is a class of transcription factor in the Zinc finger domain family. The most important function of which is to recognize various histone modifications, including histone methylation and acetylation, etc. They can also bind to DNA. Proteins with PHD domains, some of which possess histone modification enzyme activity, or can interact with histone modification enzymes, and some are associated with DNA methylation, with E3 ubiquitin ligase activity, or even can be chromatin remodeling factors. As transcriptional regulators, they play an important role in plant growth and development. In this review, we summarize the structural features and substrate binding specificity of PHD domains (including H3K4me3/0, H3K9me3, H3R2, H3K14ac) and DNA, the conservation of plant PHD domain in evolution, the molecular mechanism of known PHD domain-containing proteins in plants, providing a reference for further understanding of the involvement of these proteins during plant growth and development.植物同源结构域(plant homeodomain, PHD)是锌指结构域家族的一类转录调控因子,其最主要的功能是可以识别各种组蛋白修饰密码,包括组蛋白甲基化和乙酰化等;此外PHD结构域还可以与DNA结合。含有PHD结构域的蛋白,或者本身具有组蛋白修饰酶活性,或者可以与各类组蛋白修饰酶相互作用,还有部分与DNA甲基化相关,具有E3泛素连接酶活性,或者还可以作为染色质重塑因子,以各种不同的作用方式,在植物的生长发育过程中发挥了重要的作用。本文主要综述了结合各种类型组蛋白(包括H3K4me3/0、H3K9me3、H3R2和H3K14ac)以及DNA的PHD结构域的结构特点及其结合特异性、PHD结构域在植物中的进化保守性以及植物中已经发现的含有PHD结构域蛋白的功能及作用机制,为进一步了解该类蛋白在植物生长发育过程中如何发挥作用提供了参考。.

In this paper, a new compact staircase resonator is employed to design low-loss and high selectivity varactor-based tunable bandpass filter at 1.58-1.88 GHz on $\varepsilon_{\mathrm{r}}$=10.2,1.27 mm Duroid substrate. The proposed tunable staircase filter has a constant 3-dB fractional bandwidth of 10.6±0.5% and low insertion loss

This paper reports compact single/dual-band bandpass filters with independently controllable passbands based on a novel microstrip staircase resonator. A parallel feeding mechanism is introduced to offer better harmonics suppression on the proposed single-band BPF and also to create a second independent resonance path between the parallel feeding lines, effectively implementing compact dual-band BPF structures. Furthermore, due to the independently separated resonance paths, the passbands can be controlled independently without affecting each other. Therefore, very close frequency passbands can be effectively obtained in the proposed dual-band configuration. For demonstration and validation purposes, three miniaturized single/dual-band BPFs are designed and fabricated.

This paper introduces a compact wideband bandpass filter (WBPF) based on new miniaturized staircase interdigital resonator. The proposed filter operates at a center frequency of 2.44 GHz with a wide fractional bandwidth of 62.5% and low insertion loss equals to 0.5 dB. The filter is implemented on a Duroid substrate with 10.2 relative dielectric constant and 1.27 mm thickness. In comparison with conventional quarter-wavelength interdigital resonators, the proposed staircase resonator offers higher compactness and 28% size reduction with wide passband responses. The reported WBPF occupies a small area of 6.5 mm × 8.5 mm with an effective area of just 0.025λ2g0. Moreover, it has key merits of simple design and implementation, easy integration, and wide stopband bandwidth. The proposed filter is successfully analyzed, designed, fabricated, and measured. Experimental results have shown good agreement with simulated ones.

Additional file 2: Figure S1. ARV-825 induces strong degradation in a dose-dependent manner.

Non-uniform heat generating phenomenon is ubiquitous in real electronic devices. Based on this point, this paper researches the entropy generation rate (EGR) performance of a non-uniform heat generating (NUHG) disc. In this NUHG model, constructal design of the radial-pattern disc is performed with the conditions of constant- and variable-cross-sectional highly conductive routes (HCRs), respectively. The overall generation of heat over the entire disc area stays invariable, while the geometry of the disc is free to morph. The influence of heat generation non-uniformity on the optimized geometry of the disc is studied. The results manifest that increasing the thermal conductivity ratio and area ratio of HCRs both can reduce the EGR. Increasing the number of elements involved in the disc will compel the optimal HCRs to stretch towards the centre. In the areas with more heat generation and severer heat conduction requirement, more high conductivity material should be arranged to converge more heat flow and reduce the EGR aroused during the heat transfer process. The dimensionless EGR slumps by 11.5% on account of the employment of variable-cross-sectional HCR stratagem. Henceforth, the variable-cross-sectional HCR structure can reduce the EGR and improve its thermal performance. Additionally, the results obtained by minimizing EGR are compared with those obtained by minimizing maximum temperature difference. The primary novelty of this paper is introducing entropy generation minimization theory into the constructal design of radial-pattern disc with both non-uniform heat generation and constant- and variable-cross-sectional HCRs, which can provide benefits to the designs of practical electronic devices and the improvement of heat transfer performance.

Mass scan methods utilizing quadrupolar direct current (DC) scan were described and performed with a linear ion trap (LIT) through a home-built MS apparatus designed for ion/ion reactions. Both quadrupolar DC downscan and upscan are applicable to the LIT due to the shape of the related Mathieu stability diagram. Besides, a supplementary AC signal could be added to the DC scan process for resonant ejection, which largely enhances the signal-to-noise (S/N) ratios of the spectra. Compared with conventional resonance ejection RF scans, the scannable mass-to-charge (m/z) range in quadrupolar DC scan is much wider. Several protein cations were chosen as test molecules with a m/z scannable range larger than 140,000 Th. Besides, compared with three-dimensional (3D) quadrupolar ion traps (QIT), the LIT is a more suitable mass analyzer for ions with large m/z ratios due to large ion capacity and deep pseudopotential well depths for ions inside the trap. In general, DC scan with LIT offers a new way of rapid detection of ions with extra wide m/z scannable ranges, which has potential applications in research fields such as “top-down” proteomics and native mass spectrometry in the future.

This study aimed to construct an optimal dynamic nomogram for predicting malignant brain edema (MBE) in acute ischemic stroke (AIS) patients after endovascular thrombectomy (ET).We enrolled AIS patients after ET from May 2017 to April 2021. MBE was defined as a midline shift of5 mm at the septum pellucidum or pineal gland based on follow-up computed tomography within 5 days after ET. Multivariate logistic regression and LASSO (least absolute shrinkage and selection operator) regression were used to construct the nomogram. The area under the receiver operating characteristic curve (AUC) and decisioncurve analysis were used to compare our nomogram with two previous risk models for predicting brain edema after ET.MBE developed in 72 (21.9%) of the 329 eligible patients. Our dynamic web-based nomogram (https://successful.shinyapps.io/DynNomapp/) consisted of five parameters: basal cistern effacement, postoperative National Institutes of Health Stroke Scale (NIHSS) score, brain atrophy, hypoattenuation area, and stroke etiology. The nomogram showed good discrimination ability, with a C-index (Harrell's concordance index) of 0.925 (95% confidence interval=0.890-0.961), and good calibration (Hosmer-Lemeshow test,Our web-based dynamic nomogram reliably predicted the risk of MBE in AIS patients after ET, and hence is worthy of further evaluation.

Power supplies with several paralleled DC/DC converters are usually used for high reliability purposes owing to their advantage in terms of redundancy and modularisation. However, current unbalance due to parameter deviations among the paralleled converters might deteriorate the whole system reliability and results in excessive thermal and device stress in some individual modules. In this study, an equivalent transfer function derived from the output impedance and the voltage control loop gain. Also, a loop-shaping based robust control method is employed to design a current sharing controller utilising the proposed transfer function. Simulation and experimental results are presented to demonstrate the effectiveness of the proposed method for the parallel DC/DC converter performance improvement.

Accurate detection of early tumor margin is of great preclinical and clinical implications for predicting the survival rate of subjects and assessing the response of tumor microenvironment to chemotherapy or radiation therapy. Here, we report a multimodality optical imaging study on in vivo detection of tumor boundary by analyzing neoangiogenesis of tumor microenvironment (microangiography), microcirculatory blood flow (optical Doppler tomography) and tumor proliferation (green fluorescent protein [GFP] fluorescence). Microangiography demonstrates superior sensitivity (77.7 ± 6.4%) and specificity (98.2 ± 1.7%) over other imaging technologies (eg, optical coherence tomography) for tumor margin detection. Additionally, we report longitudinal in vivo imaging of tumor progression and show that the abrupt tumor cell proliferation did not occur until local capillary density and cerebral blood flow reached their peak approximately 2 weeks after tumor implantation. The unique capability of longitudinal multimodality imaging of tumor angio-genesis may provide new insights in tumor biology and in vivo assessment of the treatment effects on anti-angiogenesis therapy for brain cancer.

The constant power load (CPL) property of a load converter with tight control results in DC bus voltage oscillations in interconnected power converter systems. In this paper, a disturbance observer (DOB) feedforward compensation scheme is proposed to stabilize the DC bus voltage of a cascaded power converter. An equivalent DC link voltage control model and a disturbance observer are used to reconstruct the dynamic changes of the DC bus current to correct the inner current loop reference of the load converter. Simulation and experimental results show that the proposed method is effective in stabilizing the DC bus voltage.

An analytical method is proposed to reduce the memory effects and third-order intermodulation distortions for improving the linearity of wideband power amplifier (PA). An excellent linearity can be obtained by reducing the second-harmonic output power levels and reducing the envelope voltage components in the megahertz range. An improved wideband Chebyshev low-pass matching network including the bias network is analyzed and designed to validate the proposed method. The measured results indicate that a wideband high-efficiency linearized PA is realized from 1.35 to 2.45 GHz (fractional bandwidth = 58%) with power added efficiency of 60–78%, power gain of 10.8–12.3 dB, and output power of 40.0–41.2 dBm. For a 20 MHz LTE modulated signal, the adjacent channel leakage ratios (ACLRs) of the proposed PA with digital pre-distortion (DPD) linearization are −55.7 ~ −53.9 dBc across 1.5–2.4 GHz at an average output power of 32.4–33.6 dBm. For a 40 MHz two-carrier LTE modulated signal, the ACLRs of the proposed PA with DPD linearization are −51.1 ~ −48.2 dBc at an average output power of ~30.5 dBm in the frequency range from 1.5 GHz to 2.4 GHz.

In this work, a poly(l-lactic) acid (PLLA)/polyethylene oxide (PEO) nanofiber membrane was prepared by electrospinning as a carrier for the photosensitizer 5,10,15,20-tetrakis (4-carboxyphenyl) porphin (TCPP) to study the effects of singlet oxygen ( 1 O 2 ) on tumor cells. Scanning electron microscopy and confocal laser scanning microscopy images showed that the fiber surface was smooth and that TCPP was evenly dispersed in the nanofibers. TCPP, PLLA, and PEO were mixed with nanofibers without the formation of new chemical bonds, as shown by Fourier transform infrared spectroscopy. The addition of PEO improved the hydrophilicity of the nanofibers, making the contact angle of the PLLA nanofiber membrane change from 93.3° to near 0° and resulting in good cell compatibility. The sustained release experiment showed that when the amount of TCPP was 3%, the cumulative release concentration after 72 h was close to saturation in the test system. Electron spin resonance spectroscopy confirmed that TCPP produced 1 O 2 at light irradiation (532 nm). The results of in vitro cell experiments showed that TCPP@PLLA/PEO nanofiber membranes did not affect the normal growth of HeLa cells but had cytotoxic effects on cancer cells under light irradiation.

Heat shock protein 90 (HSP90) is a member of genetically conserved heat shock protein family. As an important molecular chaperone in eukaryotic cells, HSP90 plays a key regulatory role in maintaining cellular protein homeostasis. HSP90 clients encompass a wide range of proteins, thus HSP90 is involved in diverse biological process. With the deeper study, it is found that HSP90 takes an important part in the development and metastasis of cancer, and has become a promising target for the study of anticancer biology. In this review, the progress of HSP90 as molecular chaperone and its relationship with cancer are discussed.

This letter proposes a codesigned substrate integrated waveguide (SIW) filtering slot antenna with a controllable radiation null in gain response. The antenna is composed of a single-layered SIW cavity, four metalized posts, a transverse slot, and a vertical SMA connector. Four metalized posts are introduced to split the cavity into two TE 110-mode resonators. The transverse slot is utilized not only to generate radiation, but also to further split one TE110-mode resonator into two half-mode resonators. The bandpass filtering performance is achieved by the couplings between three resonators and the slot. One radiation null has been introduced for selectivity enhancement, and it will occur at the frequency where the slot is placed at about quarter-wavelength from the shorted wall of the cavity. So by changing the position of the slot, frequency of radiation null can be easily controlled, even from one side to another side of the passband. For demonstration, one antenna with a lower out-of-band radiation null and another one with an upper out-of-band radiation null have been designed, fabricated, and measured. Experimental results show that the antennas have the merits of high efficiency, high selectivity, and easily controllable radiation null.

A nonuniform heat generating model in a triangular area is built in this paper. Constructal optimizations of the models with constant and discrete variable cross-sectional high conductivity channels (HCCs) are performed by choosing minimum maximum temperature difference (MTD) as optimization objective. Optimal constructs of the triangular element and triangular first order assembly (TFOA) are obtained, respectively. The results indicate that for the TFOA with constant cross-sectional HCCs, the minimum MTD is reduced by increasing the nonuniform heat generating (NUHG) coefficient p , namely the heat conduction performance (HCP) is better when more heat generation is generated near the heat sink. The HCP of TFOA is also improved by increasing its complexity of internal structure. Furthermore, the minimum MTD of TFOA with discrete variable cross-sectional HCCs is reduced by 12.57% than that with constant cross-section. Therefore, the HCP of TFOA can be further improved by adopting discrete variable cross-sectional structures for the HCCs. The optimization results obtained from numerical calculations can provide some theoretical guidelines for the optimal heat dissipation designs of electronic devices.

Background: Our study sought to assess the effect of atorvastatin (ATV) and trimetazidine (TMZ) combination treatment in patients with non-ST elevation acute coronary syndromes (NSTE-ACS) undergoing percutaneous coronary intervention (PCI). Materials and Methods: Two hundred and fifty patients with NSTE-ACS who were undergoing PCI were enrolled in this study. Standard secondary prevention of coronary heart disease drug treatment was administered to both the groups (the ATV + TMZ group and the ATV group). In the ATV + TMZ group, patients were given 80mg of the combination medical orally 12h before PCI, 60mg 30min before PCI, and a further 20mg every day for 30t days after PCI, and. In the ATV group, patients were given only 80mg orally 12h before PCI, with a further 20mg every day for 30t days after PCI. Echocardiography was executed and plasma N-terminal pro brain natriuretic peptide (NT-pro-BNP) levels were measured just prior to the PCI and at 30 days after PCI. The major cardiovascular events (MACE) were also evaluated in both groups 30 days after PCI. Results: MACE occurred in 14.17% of patients in the ATV group and 6.50% of those in the ATV + TMZ group (P = 0.047). NT-pro-BNP levels were decreased 30 days after PCI for both groups; however, NT-pro-BNP levels in the ATV + TMZ group were significantly lower than those in the ATV group (P < .05). Cardiac function in NSTE-ACS patients, as reflected by the increased left ventricular ejection fraction, fractional shortening as well as decreased left ventricular end-diastolic dimension (P < .05) increased in all groups at 30 days after intervention, but cardiac function parameters were more significantly improved in the group administered with ATV + TMZ (P < .05). Conclusions: Our study suggests that short-term pretreatment with the combination of ATV and TMZ administration before PCI could reduce the incidence of MACE, further decrease NT-pro-BNP levels and improve cardiac function compared to a single administration of the ATV.