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When gravitational waves (GWs) pass by a massive object on its way to Earth, a strong gravitational lensing effect will happen. Thus, the GW signal will be amplified, deflected, and delayed in time. Through analyzing the lensed GW waveform, physical properties of the lens can be inferred. On the other hand, neglecting lensing effects in the analysis of GW data may induce systematic errors in the estimating of source parameters. As a space-borne GW detector, TianQin will be launched in the 2030s. It is expected to detect dozens of mergers of massive black hole binaries (MBHBs) as far as z=15 and thus will have high probability to detect at least one lensed event during the mission lifetime. In this article, we discuss the capability of TianQin to detect lensed MBHB signals. Three lens models are considered in this work: the point mass model, the singular isothermal sphere (SIS) model, and the Navarro-Frenk-White (NFW) model. The sensitive frequency band for space-borne GW detectors is around millihertz, and the corresponding GW wavelength could be comparable to the lens gravitational length scale, which requires us to account for wave diffraction effects. In calculating lensed waveforms, we adopt the approximation of geometric optics at high frequencies to accelerate computation, while precisely evaluating the diffraction integral at low frequencies. Through a Fisher analysis, we analyze the accuracy to estimate the lens parameters. We find that the accuracy can reach to the level of 10-3 for the mass of point mass and SIS lens and to the level of 10-5 for the density of the NFW lens. We also assess the impact on the accuracy of estimating the source parameters and find that the improvement of the accuracy is dominated by the increasing of signal-to-noise ratio.

This study compared the ankle‐brachial index (ABI) with transcutaneous oxygen pressure (TcPO2) in assessing peripheral vascular disease (PVD) prevalence in 100 diabetic foot ulcer (DFU) patients. Patients were categorized into vascular or nonvascular reconstruction groups and underwent both ABI and TcPO2 measurements four times over 6 months. Predictive validity for PVD diagnosis was analysed using the area under the receiver‐operating characteristic curve (AUC). The study found TcPO2 to be a superior predictor of PVD than ABI. Among the DFU patients, 51 with abnormal TcPO2 values underwent vascular reconstruction. Only TcPO2 values showed significant pretreatment differences between the groups and increased post‐reconstruction. These values declined over a 6‐month follow‐up, whereas ABI values rose. For those with end‐stage renal disease (ESRD), TcPO2 values saw a sharp decrease within 3 months. Pre‐reconstruction TcPO2 was notably lower in amputation patients versus limb salvage surgery patients. In conclusion, TcPO2 is more effective than ABI for evaluating ischemic limb perfusion and revascularization necessity. It should be prioritized as the primary follow‐up tool, especially for ESRD patients. [ABSTRACT FROM AUTHOR]

Background: Necrotizing soft-tissue infection (NSTI) is a rare and serious disease with high morbidity and mortality. Standard therapeutic concepts have included urgent surgical intervention, broad-spectrum antibiotic treatment, and intensive care. Hyperbaric oxygen therapy (HBOT) is used as adjuvant therapy in some centers, but its benefits remain controversial. Methods: A retrospective analysis was conducted in which 98 patients with a clinical diagnosis of NSTI were treated with standard treatments plus HBOT. The clinical outcomes were wound healing, performance status, hospital length, complication rate, recurrence rate, morbidity (amputation rate), and mortality. Primary or secondary outcomes were compared between the time interval of HBOT and the clinical outcomes. Results: The average times from diagnosis of NSTI to initial HBO treatment and from initial surgery to initial HBO treatment were both significantly longer in dead patients than in surviving patients (P = 0.031; P = 0.020). These two time intervals were both significantly longer in amputated patients than in preserved patients (P = 0.031; P = 0.037). Conclusions: Using combined treatment with early surgical debridement combined with HBOT, it is possible to reduce hospital stay, intensive care unit stay, number of debridements, improve complete wound healing rate, and lower amputation and mortality rates among patients with NSTI. The early onset of HBOT soon after diagnosis, especially during critical conditions, is proved to be associated with higher survival and preservation rates.

Background: The dermal regeneration template (DRT), a tissue-engineered skin substitute composing a permanent dermal matrix and an upper temporary silicone layer that serves as the epidermis, has demonstrated efficacy in treating uncomplicated diabetic foot ulcers (DFUs). Our institution has obtained good outcomes with DRT in patients with more complicated DFUs. Because of its chronicity, the authors are working to identify a clinical target that anticipates delayed healing early in the treatment in addition to determining the risk factors linked to this endpoint to increase prevention., Materials and Methods: This retrospective single-center study analyzed patients with DFUs who underwent wound reconstruction using DRT between 2016 and 2021. The patients were categorized into poor or good graft-take groups based on their DRT status on the 21st day after the application. Their relationship with complete healing (CH) rate at day 180 was analyzed. Variables were collected for risk factors for poor graft take at day 21. Independent risk factors were identified after multivariable analysis. The causes of poor graft take were also reported., Results: This study examined 80 patients (38 and 42 patients in the poor and good graft-take groups, respectively). On day 180, the CH rate was 86.3% overall, but the poor graft-take group had a significantly lower CH rate (76.3 vs. 95.2%, P =0.021) than the good graft-take group. Our analysis identified four independent risk factors: transcutaneous oxygen pressure less than 30 mmHg (odds ratio, 154.14), off-loading device usage (0.03), diabetic neuropathy (6.51), and toe wound (0.20). The most frequent cause of poor graft take was infection (44.7%), followed by vascular compromise (21.1%) and hematoma (15.8%)., Conclusion: Our study introduces the novel concept of poor graft take at day 21 associated with delayed wound healing. Four independent risk factors were identified, which allows physicians to arrange interventions to mitigate their effects or select patients more precisely. DRT represents a viable alternative to address DFUs, even in complicated wounds. A subsequent split-thickness skin graft is not always necessary to achieve CH., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.)