Directional energy weapons such as high-power microwaves and high-energy lasers pose a huge threat to optoelectronic detection systems. With that in mind, we designed an infrared optical window that ...has a nonlinear optical response to high-energy lasers and electromagnetic shielding to microwaves. By constructing a periodic metal circular hole array structure at the subwavelength scale, surface plasmons resonance is excited and its local field enhanced characteristics are utilized to form information transmission compatibility in the infrared band. At the same time, after laser etching off the subwavelength structure, the remaining metal forms a continuous conductive structure, forming an ultra-wideband shielding layer to achieve ultra-high and wide protection in the microwave band. Moreover, a layer of Ge
Sb
Te
thin film was deposited between the transparent substrate and the metal film. Utilizing its nonlinear optical properties of high-temperature phase transition to reduce damage of directed energy weapons to the photoelectric detection system and equipment. Thus, when the photoelectric detection system or device is damaged or interfered by signals of different frequency bands or energies, the filtering window can achieve multi-mode shielding function.
Strain sensors with good stability are vital to the development of wearable healthcare monitoring systems. However, the design of strain sensor with both duration stability and environmental ...stability is still a challenge. In this work, we propose an ultra-stable and washable strain sensor by embedding a coupled composite film of carbon nanotube (CNT) and Ti
3
C
2
T
x
MXene into polydimethylsiloxane (PDMS) matrix. The composite strain sensor with embedded microstructure and uneven surface makes it conformal to skin, while the CNT/MXene sensing layer exhibits a resistance sensitive to strain. This sensor shows reliable responses at different frequencies and with long-term cycling durability (over 1,000 cycles). Meanwhile, the CNT/MXene/PDMS composite strain sensor provides the advantages of superior anti-interference to temperature change and water washing. The results demonstrate less than 10% resistance changes as the temperature rises from −20 to 80 °C or after sonication in water for 120 min, respectively. The composite sensor is applied to monitor human joint motions, such as bending of finger, wrist and elbow. Moreover, the simultaneous monitoring of the electrocardiogram (ECG) signal and joint movement while riding a sports bicycle is demonstrated, enabling the great potential of the as-fabricated sensor in real-time human healthcare monitoring.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
In this letter, a graphene nanoflakes printed antenna is presented. Graphene nanoflakes conductive ink has been screenprinted on paper substrate and compressed to achieve the conductivity of 0.43 × ...10 5 S/m. Low-profile meandered-line dipole antenna has been fabricated as a proof of concept due to its electrically small size and simple structure. The maximum gain is measured to be -4 dBi, the -10-dB bandwidth ranges from 984 to 1052 MHz (6.67%), and the radiation pattern is verified as being typical radiation patterns of a dipole-type antenna. The radiation efficiency is 32%. The measurement results reveal that graphene nanoflakes printed antenna can provide practically acceptable return loss, gain, bandwidth, and radiation patterns for midand short-range RFID, and sensing applications. Furthermore, screenprinting technique employed in this work is of extremely low cost and capable of producing antennas in mass production.
In this work, the relative dielectric permittivity of graphene oxide (GO), both its real and imaginary parts, have been measured under various humidity conditions at GHz. It is demonstrated that the ...relative dielectric permittivity increases with increasing humidity due to water uptake. This finding is very different to that at a couple of MHz or lower frequency, where the relative dielectric permittivity increases with decreasing humidity. This GO electrical property was used to create a battery-free wireless radio-frequency identification (RFID) humidity sensor by coating printed graphene antenna with the GO layer. The resonance frequency as well as the backscattering phase of such GO/graphene antenna become sensitive to the surrounding humidity and can be detected by the RFID reader. This enables battery-free wireless monitoring of the local humidity with digital identification attached to any location or item and paves the way for low-cost efficient sensors for Internet of Things (IoTs) applications.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
In this paper, we report highly conductive, highly flexible, light weight and low cost printed graphene for wireless wearable communications applications. As a proof of concept, printed graphene ...enabled transmission lines and antennas on paper substrates were designed, fabricated and characterized. To explore its potentials in wearable communications applications, mechanically flexible transmission lines and antennas under various bended cases were experimentally studied. The measurement results demonstrate that the printed graphene can be used for RF signal transmitting, radiating and receiving, which represents some of the essential functionalities of RF signal processing in wireless wearable communications systems. Furthermore, the printed graphene can be processed at low temperature so that it is compatible with heat-sensitive flexible materials like papers and textiles. This work brings a step closer to the prospect to implement graphene enabled low cost and environmentally friendly wireless wearable communications systems in the near future.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Malignant brain edema (MBE) is a devastating complication in ischemic stroke. Data on MBE in patients who have had mechanical thrombectomy (MT) are relatively scarce.
To investigate the incidence, ...predictors, and clinical outcomes of MBE in patients after MT.
We included 130 consecutive patients after MT caused by anterior circulation large vessel occlusion stroke, treated with MT. MBE was defined as a midline shift of ≥5 mm on the follow-up imaging within 72 hours after MT. Characteristics of patients at admission and details of treatment were collected. The 90-day modified Rankin scale score was used as a measure of functional outcomes.
Of the 130 patients (age, 68.6±10.9 years; male, 50%), 35 (26.9%) patients developed MBE. The patients with MBE had a lower rate of functional independence (OR=7.831; 95% CI 1.731 to 35.427; p=0.008) and significantly higher mortality at 90 days (OR=7.958; 95% CI 2.274 to 27.848; p=0.001) than patients without MBE. In 104 (80%) patients with successful recanalization (modified Thrombolysis in Cerebral Infarction score of 2b-3), 24 (23.1%) patients exhibited MBE. After adjustment for confounding, ICA occlusion (OR=3.746; 95% CI 1.169 to 12.006; p=0.026) and worse collateral score (grade 1 vs grade 0: OR=0.727; 95% CI 0.192 to 2.753; p=0.638; grade 2 vs grade 0: OR=0.130; 95% CI 0.021 to 0.819; p=0.030) were significantly associated with the development of MBE, despite successful recanalization.
MBE after MT is not uncommon and was related to poor functional outcomes. Localization of a vessel occlusion and collateral status may play a role in the development of MBE.
Objective
The stromal cell-derived factor-1α/cysteine-X-cysteine chemokine receptor 4 (SDF-1α/CXCR4) axis promotes neuroprotection and angiogenesis in animal studies. Few studies have investigated ...the potential clinical implications of the SDF-1α/CXCR4 axis in patients with acute ischemic stroke (AIS). We evaluated the prognostic values of the SDF-1α/CXCR4 axis in patients with proximal middle cerebral artery occlusion.
Methods
Fifty-five patients and 18 age- and sex-matched volunteers were enrolled. Baseline clinical characteristics and risk factors of stroke were recorded. Peripheral whole blood cells were double stained with anti-CD34 and anti-CXCR4 (CD184). CD34+CXCR4+ cells were analyzed by flow cytometry. Plasma SDF-1α levels were measured by enzyme-linked immunosorbent assay.
Results
In the AIS group, plasma SDF-1α levels and the number of circulating CD34+CXCR4+ cells were significantly higher than those in controls. Day 1 SDF-1α levels were negatively correlated with infarct volume (r = −0.521) and the initial National Institutes of Health Stroke Scale score (r = −0.489). SDF-1α levels (day 1: r = −0.514; day 3: r = −0.275; day 7: r = −0.375) and circulating CD34+CXCR4+ cells (day 7: r = −0.282) were inversely associated with the 90-day modified Rankin Scale score.
Conclusion
The SDF-1α/CXCR4 axis has potential applications for predicting the clinical outcome of AIS.
Background:
Blood pressure (BP), recanalization status, and collateral circulation are important factors for cerebral autoregulation after stroke. We aimed to investigate the association of various ...BP variability (BPV) parameters with clinical outcomes after mechanical thrombectomy (MT) according to recanalization and collateral status.
Methods:
We included 502 consecutive patients who underwent MT due to anterior circulation large vessel occlusion stroke at three comprehensive stroke centers. BPV parameters were standard deviation (SD), maximum/minimum BP, coefficient of variation (CV) and successive variation (SV). The clinical outcomes included 90-day functional outcome assessed by modified Rankin Scale score and symptomatic intracranial hemorrhage (sICH).
Results:
Among the included patients, 219 (43.6%) achieved good functional outcomes and 59 (11.8%) developed sICH. After adjusting for confounders, higher systolic BP (SBP) variability CV (odds ratio (OR), 1.089, p = 0.035), SV (OR, 1.082, p = 0.004). and SD (OR, 1.074, p = 0.027) was associated with a lower likelihood of a favorable outcome. In addition, higher SBP CV (OR, 1.156, p = 0.001) and SD (OR, 1.118, p = 0.001) were significantly associated with increased odds of sICH. Moreover, the relationship between BPV and the outcomes depended on recanalization status. However, regardless of collateral status, a higher BPV after MT was associated with worse outcomes.
Conclusions:
Higher SBP SD and CV during the first 24 h after MT was a powerful predictor of worse clinical outcomes, regardless of the collateral status. However, the effects of BPV on outcomes were more substantial among patients with successful reperfusion.
This letter presents a novel low phase noise freerunning oscillator based on a high selectivity bandpass filter (BPF) using a composite right/left-handed transmission line (CRLH TL). The oscillator ...is designed at the spectrum-based quality factor (Qs) peak frequency to achieve low phase noise performance. Ata center frequency of 2.05 GHz, the oscillator demonstrates, experimentally, a phase noise of -150.4 dBc/Hz at 1 MHz frequency, offset with a figure of merit(FOM) of -207.2 dBc/Hz, less than -32 dBm spurious harmonics, and total oscillator power consumption of 6.1 mW from a 2 V supply voltage.
Traditional cervical cancer diagnosis mainly relies on human papillomavirus (HPV) concentration testing. Considering that HPV concentrations vary from individual to individual and fluctuate over ...time, this method requires multiple tests, leading to high costs. Recently, some scholars have focused on the method of cervical cytology for diagnosis. However, cervical cancer cells have complex textural characteristics and small differences between different cell subtypes, which brings great challenges for high-precision screening of cervical cancer. In this paper, we propose a high-precision cervical cancer precancerous lesion screening classification method based on ConvNeXt, utilizing self-supervised data augmentation and ensemble learning strategies to achieve cervical cancer cell feature extraction and inter-class discrimination, respectively. We used the Deep Cervical Cytological Levels (DCCL) dataset, which includes 1167 cervical cytology specimens from participants aged 32 to 67, for algorithm training and validation. We tested our method on the DCCL dataset, and the final classification accuracy was 8.85% higher than that of previous advanced models, which means that our method has significant advantages compared to other advanced methods.
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