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BackgroundStroke is a devastating disease and ranks as the second leading cause of death and disability globally. Several studies have shown that preceding infection (PI) of upper respiratory tract are strongly associated with acute ischemic stroke (AIS). However, the clinical implications and underlying pathological mechanisms remain unclear.MethodsIn this study, 16S rRNA gene sequencing was employed to compare the structural characteristics of oropharyngeal and gut microbiota in AIS patients with or without PI and normal controls (NCs; 30 cases each), and systemic inflammatory markers were detected to explore the relationship between upper respiratory tract infections (URTIs) and subsequent stroke severity and functional outcome and the potential mechanism.ResultsWe found that patients with AIS-PI exhibited elevated serum WBC, NE, CRP, and Hcy levels, as well as a higher 90-day mRS score. Oropharyngeal and gut microbiota analysis showed that AIS and AIS-PI patients exhibited increased microbial richness in sequence. Principal coordinate analysis of the microbiota demonstrated significant differences in microbiota composition among the three groups. In AIS-PI patients, Megamonas, Megasphaera, Ruminococcaceae UCG 004, Rothia, and Streptococcus were significantly enriched in the gut. Opportunistic pathogens, including Thermus, uncultured Veillonella sp., and Oribacterium sinu, were found to be significantly enriched in the oropharynx. The dysregulated microbiota were positively correlated with systemic inflammatory markers, stroke severity, and poor prognosis. In contrast, short-chain fatty acid-producing bacteria Eisenbergiella, bacterium NLAE, Fusicatenibacter, Ruminococcaceae, and Faecalibacterium were enriched in NCs. Their abundances were negatively correlated with systemic inflammatory markers, stroke severity and poor prognosis.ConclusionOur findings suggest that PIs of the upper respiratory tract may contribute to poor short-term functional outcome in AIS patients by causing disturbance of the oropharyngeal and gut microbiota and promoting elevated systemic inflammation levels.

BackgroundVentilator-Associated Pneumonia (VAP) severely impacts stroke patients’ prognosis after endovascular treatment. Hence, this study created a nomogram to predict the occurrence of VAP after endovascular treatment.MethodsThe individuals with acute ischemic stroke and large vessel occlusion (AIS-LVO) who received mechanical ventilation and endovascular therapy between July 2020 and August 2023 were included in this retrospective study. The predictive model and nomogram were generated by performing feature selection optimization using the LASSO regression model and multifactor logistic regression analysis and assessed the evaluation, verification and clinical application.ResultsA total of 184 individuals (average age 61.85 ± 13.25 years, 73.37% male) were enrolled, and the rate of VAP occurrence was found to be 57.07%. Factors such as the Glasgow Coma Scale (GCS) score, duration of stay in the Intensive Care Unit (ICU), dysphagia, Fazekas scale 2 and admission diastolic blood pressure were found to be associated with the occurrence of VAP in the nomogram that demonstrating a strong discriminatory power with AUC of 0.862 (95% CI, 0.810–0.914), and a favorable clinical net benefit.ConclusionThis nomogram, comprising GCS score, ICU duration, dysphagia, Fazekas scale 2 and admission diastolic blood pressure, can aid clinicians in predicting the identification of high-risk patients for VAP following endovascular treatment in large vessel occlusion stroke.

Based on 3D printing technology, this paper investigates the effects of the printing process and reinforcement materials on the performance of 3D-printed glass bead insulation mortar. In order to improve and enhance the performance of the mortar, two sets of tests were designed for research and analysis. Firstly, by changing the direction of the interlayer printing strips, the anisotropy of the specimens in different paths was analyzed, and then the effect of different dosages of different fibers on the performance of 3D-printed glass bead insulation mortar was investigated by adding reinforcing materials. The results show that the path a specimen in the X direction’s compressive strength is the best; in the Y direction, flexural strength is the best; the path b specimen in the Y direction’s compressive strength is the best; in the Z direction, flexural strength is the best, but the compressive and flexural strengths are lower than the strength of the specimen without 3D printing (cast-in-place specimen); and adding reinforcing materials mortar not only has high strength but also has good printability and excellent thermal insulation. This paper provides a theoretical basis and reference value for the popularization and application of 3D printing thermal insulation mortar technology.

Macromolecules exhibit ordered structures and complex functions in an aqueous environment with strong thermodynamic fluctuations [...]

In this study, a skin gas detection system based on quartz enhanced photoacoustic spectroscopy (QEPAS) with a constant temperature collection chamber and an automatic frequency adjustment function was used to collect and monitor carbon dioxide (CO2) emissions from human skin. The detection element of the system is an on-beam structure assembled by a 30.72 kHz quartz tuning fork (QTF). A laser with a wavelength of 4991.26 cm−1 is emitted (with a wavelength adjustment range of 10 cm−1) to excite the QTF. When the integration time is 365 s, the system can achieve a minimum detection limit (MDL) of 2.6 ppmv. The sensitivity of the system is 636.9 ppmv/V. The gas detection system is used to monitor the concentration of CO2 emissions from different parts of the skin and the same part covered by different cosmetics. The CO2 emission rate is defined as the ratio of the skin gas monitoring time of 25 min to the CO2 concentration variable in the gas chamber (volume of 8 mL). The results were collected from three healthy volunteers. Among the six different parts, the cheeks emitted the fastest rate (the average rate was 365.5 ppmv/min) of CO2, and the thighs emitted the slowest rate (the average rate was 56.4 ppmv/min) of CO2. Comparing the experimental results of the six sites at different times, the order of the CO2 emission rate is identical for all six sites. In the experiments with the three cosmetic products (experimental site: forearm), comparing the CO2 emission rate from clean skin with the CO2 emission rate from cosmetic-covered skin shows that sunscreen is the most breathable, followed by barrier cream, and foundation is the least breathable.

We theoretically analyze and experimentally demonstrate improved half-wave couplers for widely tunable V-cavity lasers. An overlapping-image 6×6 MMI coupler and an aggregating-image 16×16 MMI coupler are investigated, which give optimal coupling phase and coefficient for achieving high single-mode selectivity in V-cavity lasers while producing a low loss. A single-electrode controlled tuning of 38 channels is achieved with channel spacings of 100 GHz and 150 GHz. By combining two single-electrode tuning segments at different temperatures, a wavelength tuning range of 52 channels from 1515 nm to 1585 nm is obtained, and the side mode suppression ratios (SMSRs) reach 45 dB.

A monolithic 8 × 8 transmitter-router chip fabricated on InGaAlAs-InP multi-quantum well wafer for distributed wavelength routing network in the O-band with a channel spacing of 400 GHz is experimentally demonstrated. A tunable V-cavity laser (VCL) array, a cyclic-arrayed waveguide grating router (AWGR) and a semiconductor amplifier (SOA) array are integrated using the quantum-well intermixing (QWI) technique for its fabrication simplicity and cost effectiveness. A 200 GHz-spaced compact-size VCL is demonstrated with a 27 nm tuning range and a side-mode suppression ratio (SMSR) around 40 dB using a single-electrode controlled tuning. The chip output power is 24.6 mW. Measurement results of the transmitter-router chip show that all 64 input-output combinations have cyclic response spectra. After passing through the SOA with 80 mA bias current, an output power of about 9.6 mW and optical signal-to-noise ratio (OSNR) up to 39 dB have been measured. The demonstrated transmitter-router chip is fabricated on the same quantum well structure without requiring multiple epitaxial growth and complex grating fabrication. The characteristics of multi-wavelength and multi-port transmissions enable the distributed optical routing networks with flexible bandwidth allocation, which can find wide application in datacenters and high-performance computers.

Directly modulated tunable lasers are highly desirable for constructing dense-wavelength division multiplexing (DWDM) access networks, owing to their advantages of low cost, compact size and low power consumption. However, the transmission distance for 10 Gbps is usually limited to about 10 km in the telecom C-band in standard single-mode fiber (SMF) due to wavelength chirp. Here we propose and demonstrate a simple technique for extending the transmission distance by detuning the wavelength of a tunable V-cavity laser with respect to DWDM multiplexers. Experiment results show that 10 Gbps signal can be transmitted error-free (BER-12) over 20 km SMF with a wavelength-detuning with respect to a Gaussian-type arrayed waveguide grating (AWG) without dispersion compensation. The power penalty is only 1 dB compared to the back-to-back transmission.

We report a widely tunable V-cavity laser monolithically integrated with an electro-absorption modulator (EAM). The device shows a 41-nm wavelength tunability covering 51 channels at 100 GHz spacing on the ITU grid, with a side-mode suppression ratio (SMSR) higher than 47 dB. Error-free transmission over 50 km standard single-mode fiber at 10 Gb/s is demonstrated at all wavelengths over the tuning range. The integrated EAM exhibits a dynamic extinction ratio higher than 12.5 dB. The bit-error-rate measurements show a power penalty less than 3 dB for 50-km transmission. The results demonstrate that this ultra-compact and regrowth-free electro-absorption modulated tunable laser can be a cost-effective transmitter solution for DWDM metropolitan and access networks.

Hyperhomocysteinemia is an independent risk factor for cardiovascular impairment in hypertension. Oxidative stress is important in the molecular mechanisms associated with hypertension, but there are few studies focusing on the comparison of oxidative stress biomarkers in hypertensive patients with or without hyperhomocysteinemia. The study included 50 newly diagnosed hypertensive patients with hyperhomocysteinemia, 50 newly diagnosed hypertensive patients without hyperhomocysteinemia, and 50 age-matched healthy controls. Serum levels of malondialdehyde, nitric oxide, 8-isoprostane-F2ɑ, superoxide dismutase, catalase, and glutathione peroxides were compared. Levels of malondialdehyde and 8-isoprostane-F2ɑ were higher in both hypertensive groups than in the control group (8.3 ± 1.8 μmol/L vs. 6.5 ± 1.3 μmol/L vs. 4.3 ± 1.2 μmol/L, P

Electrocardiogram (ECG) data analysis is of great significance to the diagnosis of cardiovascular disease. ECG compression should be processed in real time, and the data should be based on lossless compression and have high predictability. In terms of the real time aspect, short-time Fourier transformation is applied to the processing of signal wave for reducing computational time. For the lossless compression requirement, wavelet-transformation that is a coding algorithm can be used to avoid loss of data. In practice, compression is required to avoid storing redundant recording data that are not useful in the diagnosis platform. The obtained data can be preprocessed to remove noise by using wavelet transform, and then a multi-objective optimize neural network model is used to extract feature information. Compared with the existing traditional methods such as direct data processing method and transform method, our proposed compression model has self-learning ability to achieve high data compression ratio at 1:19 without losing important ECG information and compromising quality. Upon testing, we demonstrated that the proposed ECG data compression method based on multi-objective optimization neural network is effective and efficient in clinical practice.

Physical exercise increase is confirmed as a fundamental treatment for hypercholesterolemia patients, but the effect on the arterial stiffness and oxidative stress is still unclear. 74 hypercholesterolemia patients were divided into 2 groups. The exercise group received dietary recommendations and a 3-month exercise program, prescribed according to their first cardiopulmonary exercise tests(CPET), while the control group only received dietary recommendations. All patients underwent blood tests, CPET and brachial-ankle pulse wave velocity (baPWV) studies at enrollment and at 3 months' follow-up. At the end of 3 months, there was no change in total cholesterol (TC) level in either group. However, in the exercise group, we found maximal exercise parameters increased and baPWV values declined. Meanwhile, there were significant changes in the level of malondialdehyde, 8-isoprostane-F2α and superoxide dis-mutase. Moreover, the change of baPWV was positively correlated with the change of 8-isoprostane-F2α (r = 0.36, P < 0.01). In the control group, no change in baPWV or oxidative bio-marker was observed. Our findings suggested that regular aerobic exercise could lessen arterial stiffness in hypercholesterolemia patients, even in the context of no obvious TC decrease. During this process, favorable adjustment in oxidative stress might be an important pathway, which remains to be further explored. [ABSTRACT FROM AUTHOR]