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Background Glucocorticoid-induced osteonecrosis of the femoral head (ONFH) is closely associated with the dysfunction of the bone microvascular endothelial cells (BMECs). The present study investigated the angiogenic and apoptotic activity of the BMECs in glucocorticoid-induced ONFH. Methods This study enrolled a total of 12 patients, six of whom were assigned to the ONFH group whereas the other six served as the control group. The ONFH group was composed of patients with glucocorticoid-induced ONFH while the control group had femoral neck fractures. BMECs were isolated from the subchondral region of the femoral head. Cell proliferation, cell viability, tube formation assay, Transwell assay, TUNEL assay, and Western blot analysis were performed. Results BMECs of the two groups were successfully isolated and identified. No significant differences were noticed in BMECs proliferation between the two groups. However, compared to the control, cell viability, tube formation, and migration of BMECs were significantly decreased and the number of TUNEL positive cells was markedly increased in the ONFH group. In the ONFH group, it was also noted that the amount of Bax and cleaved-caspase3 was elevated while that of Bcl-2 was reduced. Conclusion The findings of our study revealed that BMECs obtained from the glucocorticoid-induced ONFH patients had decreased angiogenic and increased apoptotic activities, which could explain the pathogenesis and progression of glucocorticoid-induced ONFH.

The synthetic aperture passive positioning (SAPP) method has attracted the attention of researchers due to its high positioning resolution. However, there are still key technical issues regarding SAPP methods, such as residual frequency offset (RFO) coupling at Doppler frequency leading to decreased positioning accuracy, and non-periodic discontinuous signals emitted by unknown radiation sources (NRSs) causing positioning algorithm failure. Therefore, this paper proposes an ultra-short baseline SAPP method based on interferometer assistance. Firstly, conjugate multiplication is applied to the received signals of the interferometer’s dual antennas to obtain a single frequency received signal corresponding to the straight-line distance. Subsequently, the proposed step search (SS) algorithm based on cross-correlation analysis is used to obtain the receiving frequency of the single frequency signal, and the initial positioning distance is calculated using the corresponding mapping relationship based on this frequency. Finally, NRS positioning is completed in the two-dimensional coordinates of azimuth and range by combining with the signal arrival angle. The positioning results of this method are insensitive to RFO, and even if NRS emits non-periodic discontinuous signals, the proposed method can successfully locate them. In addition, the Cramer–Rao lower bound (CRLB) of the localization for this method is derived. The simulation and unmanned aerial vehicle (UAV) experimental results demonstrate the effectiveness and feasibility of this method.

Renal interstitial fibrosis is a common pathway for the progression of chronic kidney disease (CKD) to end-stage renal disease. Renalase, acting as a signaling molecule, has been reported to have cardiovascular and renal protective effects. However, its role in renal fibrosis remains unknown. In this study, we evaluated the therapeutic efficacy of renalase in rats with complete unilateral ureteral obstruction (UUO) and examined the inhibitory effects of renalase on transforming growth factor-β1 (TGF-β1)-induced epithelial–mesenchymal transition (EMT) in human proximal renal tubular epithelial (HK-2) cells. We found that in the UUO model, the expression of renalase was markedly downregulated and adenoviral-mediated expression of renalase significantly attenuated renal interstitial fibrosis, as evidenced by the maintenance of E-cadherin expression and suppressed expression of α-smooth muscle actin (α-SMA), fibronectin and collagen-I. In vitro, renalase inhibited TGF-β1-mediated upregulation of α-SMA and downregulation of E-cadherin. Increased levels of Phospho-extracellular regulated protein kinases (p-ERK1/2) in TGF-β1-stimulated cells were reversed by renalase cotreatment. When ERK1 was overexpressed, the inhibition of TGF-β1-induced EMT and fibrosis mediated by renalase was attenuated. Our study provides the first evidence that renalase can ameliorate renal interstitial fibrosis by suppression of tubular EMT through inhibition of the ERK pathway. These results suggest that renalase has potential renoprotective effects in renal interstitial fibrosis and may be an effective agent for slowing CKD progression.

What are the main findings? This study proposes for the first time a multiplexing communication method for SAR scatter-wave jamming: a method based on slow-time small phase modulation. This study demonstrates that the proposed method can achieve reliable information transmission while maintaining effective scatter-wave jamming, with a controllable trade-off between BER performance and azimuth focusing quality. What are the implications of the main findings? SAR scatter-wave jamming signals can be reused as communication carriers, improve spectrum utilization and expand the functionality of SAR electronic countermeasures systems. They also provide a theoretical basis for the joint design of jamming performance and embedded communication capabilities in future integrated radar countermeasure systems. This paper proposes a novel jamming multiplexing communication method for synthetic aperture radar (SAR) imaging in scatter-wave jamming (SWJ) scenarios. This method multiplexes communication information by modulating a weak phase in the slow time dimension of the SWJ signal. After receiving the signal, the ground communication station (CS) extracts the information according to the designed algorithm, thus achieving communication transmission. Specifically, a detailed signal model is established to describe the modulation and demodulation mechanism of the communication information. The impact of communication modulation on the SAR image is theoretically analyzed, and the bit error rate (BER) performance of the communication transmission is evaluated. Due to the use of high-gain matched filtering technology in the communication demodulation process, the proposed method achieves better communication BER performance in low signal-to-noise ratio (SNR) environments without significantly reducing jamming performance. Simulation results show that the proposed method achieves reliable information transmission while maintaining effective SWJ capability.

In this article, we propose a joint waveform based on universal filtered multicarrier (UFMC) chirp for radar jamming and communication joint systems. Modulation of radar jamming chirp signals and communication signals on different subcarrier groups in the UFMC sub-band is used to achieve the waveform design. The jamming signal in the waveform contains a frequency shift coefficient that depends on the delay time, which can effectively improve the anti-frequency hopping ability and enhance the overall jamming efficiency. Simultaneously jamming signals can provide assistance in channel estimation and equalization of communication, improving the information transmission quality of communication subsystems. We concluded through reasonable trade-off analysis that the combined weight of radar jamming and communication is closely related to the overall performance of the waveform. The simulation results show that the proposed UFMC chirp synthesized waveform has good jamming and communication performance. Software defined radio (SDR) simulation experiments demonstrated the effectiveness of this method in practical environments.

To meet the multi-device integration requirements faced by electronic warfare systems in the current environment and to address the problem of conventional jamming-based imaging algorithms being unable to achieve a high range resolution under narrowband conditions, this paper proposes a broadband high-resolution synthetic aperture radar (SAR) imaging method based on narrowband dense false target jamming signals (DFTJSs). The characteristic of this signal is its ability to modulate large bandwidth phase information for each narrowband false target jamming signal (FTJS) so that the echo of the entire jamming signal has a secondary compression characteristic in the distance direction without affecting its jamming ability, thereby eliminating the influence of the first compression distance blur and obtaining a high resolution of the large bandwidth signal. Theoretical analysis and numerical simulations indicate that narrowband DFTJSs using phase modulation can achieve high-resolution imaging of specific target areas while causing interference to non-cooperative radar (NCR).

The melanoidins produced by the Maillard reaction give foods a golden, brown or black color and release aromatic compounds. Investigating the molecular structure and pyrolysis characteristics of melanoidins provides insight into improving food quality. Seven hydrosoluble colored fractions were isolated from three melanoidins (glycine/glucose (Gly–Glc), proline/glucose (Pro–Glc), and phenylalanine/glucose (Phe–Glc)) using size exclusion and C18 chromatography. Fractions with lower molecular weights (Mw: 5958– 20,106 Da) exhibited deeper colors (browning index: 0.783–3.044). For melanoidins derived from polar amino acids (glycine), low-polarity fractions contributed more to color, while for those from non-polar amino acids (proline), high-polarity fractions were more significant. Mass spectrometry revealed consistent polymerization patterns involving glyoxylic acid and glyoxal across fractions (mass-to-charge differences of 74 m/z and 58 m/z). NMR analysis indicated that Pro–Glc fractions contained more glucose skeletons, whereas Phe–Glc fractions exhibited benzene-ring features. After pyrolysis, furans, pyrroles, and cyclopentenones were major volatiles in Gly–Glc fractions, with pyrroles and DDMP dominating Pro–Glc fractions, and phenyl-containing compounds prevalent in Phe–Glc fractions. These findings suggest amino acids influence both melanoidin structure and glucose-derived skeletons, providing a foundation for controlling color and aroma formation during processing such as baked foods, roasted meats, coffee, dairy products and fermented foods.

A low-complexity stochastic dynamic element matching (DEM) technique to mitigate the distortions caused by the nonlinearity of multi-bit digital-to-analog converters (DACs) in sigma-delta modulator is proposed. Multi-bit DAC noise is analyzed in detail from a signal processing point-of-view in this research, and then implementation of the basic stochastic unit named swapper cell which includes bar state and cross state controlled by a 1-bit pseudo-random noise signal, is illustrated. To reduce the hardware complexity, a multi-layer scheme for multi-input multi-output stochastic encoder is presented and demonstrated based on rigorous mathematical derivation. For a n-input n-output version, the number of the switch elements employed in the proposed encoder is reduced to 2nlog2n from the conventional n!. Simulation results show that, with the use of the stochastic encoder, severe harmonic distortions resulted by the DAC elements mismatch errors are suppressed effectively. When the proposed encoders are applied to the internal multi-bit DACs in sigma-delta (ΣΔ) modulators, large improvements of the linearity performance of the modulators are achieved. Additionally, the analyses and explanations for this stochastic scheme provide a theoretical foundation for the future development of noise shaping DEM.

Talcose molybdenite resources are abundant but resource utilization is low. The floatation separation of molybdenite (MoS2) and talc is challenging due to their similar natural hydrophobicity and layered structures. This study investigates the surface properties and interaction mechanisms between these minerals to improve their separation efficiency. Density functional theory (DFT) calculations confirm that the basal planes of both minerals are hydrophobic, while their edge surfaces are hydrophilic. Atomic force microscopy (AFM) and DLVO theory reveal that molybdenite and talc particles aggregate in neutral/acidic conditions but disperse in alkaline solutions due to altered surface forces. Floatation experiments demonstrate that pulp pH is the key controlling factor—alkaline conditions (pH > 10) effectively reduce hetero-aggregation, enabling selective molybdenite recovery. These findings provide critical insights into optimizing floatation processes for talcose molybdenite ores, enhancing resource utilization.

Background: Controversy exists concerning whether tenotomy or tenodesis is the optimal surgical treatment option for proximal biceps tendon lesions. Purpose: To evaluate the clinical outcomes after arthroscopic tenodesis and tenotomy in the treatment of long head of the biceps tendon (LHBT) lesions. Study Design: Systematic review; Level of evidence, 4. Methods: A systematic review was performed by searching PubMed, the Cochrane Library, Web of Science, and Embase to identify randomized controlled trials (RCTs) and cohort studies that compared the clinical efficacy of tenotomy with that of tenodesis for LHBT lesions. A standardized data extraction form was predesigned to obtain bibliographic information of the study as well as patient, intervention, comparison, and outcome data. A random-effects model was used to pool quantitative data from the primary outcomes. Results: A total of 21 eligible studies were separated into 3 methodological groups: (1) 4 RCTs with level 1 evidence, (2) 3 RCTs and 4 prospective cohort studies with level 2 evidence, and (3) 10 retrospective cohort studies with level 3 to 4 evidence. Analysis of the 3 groups demonstrated a significantly higher risk of the Popeye sign after tenotomy versus tenodesis (group 1: risk ratio [RR], 3.29 [95% CI, 1.92-5.49]; group 2: RR, 2.35 [95% CI, 1.43-3.85]; and group 3: RR, 2.57 [95% CI, 1.33-4.98]). Arm cramping pain remained significantly higher after tenotomy only in the retrospective cohort group (RR, 2.17 [95% CI, 1.20-3.95]). The Constant score for tenotomy was significantly worse than that for tenodesis in the prospective cohort group (standardized mean difference [SMD], –0.47 [95% CI, –0.73 to –0.21]), as were the forearm supination strength index (SMD, –0.75 [95% CI, –1.28 to –0.21]) and the Simple Shoulder Test (SST) score (SMD, –0.60 [95% CI, –0.94 to –0.27]). Conclusion: The results demonstrated that compared with tenodesis, tenotomy had a higher risk of a Popeye deformity in all 3 study groups; worse functional outcomes in terms of the Constant score, forearm supination strength index, and SST score according to prospective cohort studies; and a higher incidence of arm cramping pain according to retrospective cohort studies.