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Abstract Background Lymphoma is the most common secondary cause of hemophagocytic lymphohistiocytosis (HLH) in adults. Lymphoma‐associated HLH (LA‐HLH) in the elderly population is not rare, however, little has been reported regarding clinicopathological characteristics, prognostic factors, and outcomes of LA‐HLH in the elderly population. Methods We retrospectively analyzed a multicenter cohort of elderly patients with LA‐HLH. Clinicopathological features and treatment information were collected. The impacts of baseline characteristics and treatments on survival outcomes were analyzed. Results A total of 173 elderly patients with LA‐HLH were included. Compared with young patients, elderly patients showed different clinical and laboratory features. Regarding lymphoma subtypes, B‐cell lymphoma was more common in elderly patients (elderly 61.3% vs. young 32.3%, p 1407 U/L), and a higher creatinine level (>96.8 μmol/L) were independent predictors of decreased overall survival and 60‐day survival. A prognostic index was established and demonstrated to be robust in predicting the overall survival and 60‐day survival of elderly patients with LA‐HLH. Conclusions LA‐HLH in elderly patients displayed heterogeneous clinicopathological features and survival outcomes. Treatments need to be optimized to improve the outcomes of elderly patients with LA‐HLH.

Considering the rapid time-varying channel conditions and large Doppler frequency fluctuations caused by high-speed movement of unmanned aerial vehicles, this paper proposes a non-stationary channel emulation scheme for Unmanned Aerial Vehicles(UAVs) using a field-programmable gate array platform. The proposed scheme adopts the sum of frequency modulation method to generate non-stationary channel fading and proposes a real-time algorithm for generating channel parameters to improve the real-time performance of channel emulation and ensure the real-time updating of channel status. In addition, to address the issue of power random fluctuation caused by large Doppler frequency fluctuations, this paper designs an adaptive power equalization module that ensures the stability of fading power by limiting the maximum fluctuation to only 1.13%. Finally, the results of hardware resource consumption analysis demonstrate that the proposed approach in this study significantly reduces the utilization of storage resources compared to replay-based and pre-stored solutions, with reductions of 52.44% and 9.31%, respectively. This makes the proposed approach well-suited for simulating long-duration non-stationary channel fading in UAV scenarios. Additionally, the measured analysis results demon-strate that the channel characteristics output by the proposed hardware emulation scheme, such as path loss and Doppler power spectrum density,closely align with theoretical results when compared to the emulation scheme without the equalizer. This research can be applied to the design and optimization of UAVs communication systems.

Summary: Background: Respiratory syncytial virus (RSV) has posed substantial morbidity and mortality burden to young children and older adults globally. The coronavirus disease 2019 (COVID-19) pandemic was reported to have altered RSV epidemiology and could have important implications for RSV prevention and control strategies. We aimed to compare RSV epidemiology in different phases of the COVID-19 pandemic with the pre-pandemic period by leveraging epidemiological, molecular, and serological data collected from a prospective respiratory pathogen surveillance and serology study. Methods: This study was based on the data during July 1, 2015 to November 30, 2023 from the Respiratory Pathogen Surveillance System (RPSS), a sentinel-hospital based surveillance system of acute respiratory infections consisting of 35 hospitals that represent residents of all ages from all 16 districts in Beijing, China. RSV infection status was tested by RT-PCR and gene sequencing and phylogenetic analysis was conducted among the identified RSV strains. We further supplemented RPSS data with three serology surveys conducted during 2017–2023 that tested RSV IgG levels from serum specimens. RSV detection rate was calculated by calendar month and compared across RSV seasons (defined as the July 1 through June 30 of the following year). RSV IgG positivity proportion was calculated by quarter of the year and was correlated with quarterly aggregated RSV detection rate for understanding the relationship between infection and immunity at the population level. Findings: Overall, a total of 52,931 respiratory specimens were collected and tested over the study period. RSV detection rates ranged from 1.24% (94/7594) in the 2017–2018 season to 2.80% (219/7824) in the 2018–2019 season, and from 1.06% (55/5165) in the 2022–2023 season to 2.98% (147/4938) in the 2021–2022 season during the pre-pandemic and pandemic period, respectively. ON1 and BA9 remained the predominant genotypes during the pandemic period; no novel RSV strains were identified. RSV circulation followed a winter-months seasonal pattern in most seasons. One exception was the 2020–2021 season when an extensive year-round circulation was observed, possibly associated with partial relaxation of non-pharmaceutical interventions (NPIs). The other exception was the 2022–2023 season when very low RSV activity was observed during the usual winter months (possibly due to the concurrent local COVID-19 epidemic), and followed by an out-of-season resurgence in the spring, with RSV detection persisting to the end of the study period (November 2023). During the two seasons above, we noted an age-group related asynchrony in the RSV detection rate; the RSV detection rate in young children remained similar (or even increased with borderline significance; 43/594, 7.24%, and 42/556, 7.55% vs 292/5293, 5.52%; P = 0.10 and P = 0.06, respectively) compared with the pre-pandemic seasons whereas the detection rate in older adults decreased significantly (8/1779, 0.45%, and 3/2021, 0.15% vs 160/10,348, 1.55%; P

To ensure the performance of C/C composites, a surface-modified C/C composite was prepared with a C/C composite as the substrate, one-dimensional SiC as the intermediate, and vertically oriented graphene as the modification material without changing the microstructure or composition of the C/C composites. C/C composite surface modifications were prepared in two steps. Its specific surface area is improved from 0.25 m2/g to 10.44 m2/g, and the electromagnetic interference shielding efficiency is enhanced from 13.08 dB to 23.86 dB. Different from the C/C composites without surface modification, the electromagnetic interference shielding mechanism of surface-modified C/C composites changed from electromagnetic reflection to the interaction of electromagnetic absorption and reflection. The reason is that the increased specific surface area elongates the transmission paths of the electromagnetic waves by multiple reflections, leading to significantly improved electromagnetic interference shielding efficiency.

Abstract The non‐noble Mn coordinated N, P co‐doping graphene materials were investigated theoretically in this work based on density functional theory calculation. The electronic structure is effectively tuned after the introduction of P heteroatom. The moderate d band center and density of states at Fermi energy of MnN4‐P1‐G indicate that it is of modest adsorption ability for these O‐containing intermediates. The rank of adsorption energies of O‐containing intermediates for MnN4‐P1‐G is OH* > 2OH* > OOH* > O* > O2* > H2O*, whereas the MnN4‐P1‐G favors a four‐electron process instead of two‐electron process. The doping of P on MnN4‐P1‐G can increase the kinetic activity for the rate‐determining step as well as the Ulim for MnN4‐P1‐G significantly increases from 0.38 to 0.45 V compared with MnN4‐G. The spin density and magnetic moments of Mn are effectively tuned by d, p hybridization to lower the adsorption energy of OH intermediates (rate‐determining step [RDS]) so as to improve the catalytic activity. It is concluded that the P‐doped MnN4 catalysts with excellent oxygen reduction reaction activity can be obtained and this study can provide theoretical guidance for the rational design of high‐performance Mn‐based carbon materials catalysts.